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  • 1.
    Almgren, Anna
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Material- och tillverkningsteknikval för en stol åt Källemo2014Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta projekt har pågått under sista terminen på maskiningenjörsprogrammet vid högskolan i Halmstad. Projektet har utförts av en student och tillsammans med företaget Källemo. Syftet med projektet har varit att studenten ska hitta och utvärdera ett lämpligt material åt en ny stol. Materialvalet skulle också kompletteras med en lämplig tillverkningsmetod. Stolen är designad av Pierre Sindre, SandellSandberg, och kommer att produceras och säljas av Källemo. Pierre Sindres ritningar och renderingar var underlaget som var utgångspunkt för projektet. Arbetet har inneburit att olika material har utvärderats och framförallt formpressad filt. Lämpligheten har testat genom liknande referensmöbler och fysiska tester. Bland annat har provbitar testat med enkla handtester. En dialog har också förts med leverantörer av material som haft mycket erfarenhet och kunnat bidra med tips och idéer.  Då projektet inte har varit ett typiskt konstruktionsprojekt har metoden utvecklats efterhand som olika resultat uppkommit. Detta har varit ett arbetssätt som har varit väldigt lärorikt för studenten och också väldigt tidseffektivt då ingen onödig tid har lagt på irrelevanta processer. Varje steg i arbetets gång har diskuterats med både uppdragsgivaren på företaget och två handledare som högskolan tillhandahållit. Veckomöten varje vecka har också bidragit till ett mycket tidseffektivt arbete där snedsteg tidigt kunnat upptäckas av de med mer erfarenhet. Dessa möten har varit avgörande för det goda resultatet som erhållits. Resultatet består av fem lösningsförslag som tagits fram och vid diskussion med företaget och leverantörer utmynnat i ett slutligt resultat som nu är färdigt för produktion. När projektet avslutades var den första delen i produktion och således målet med projektet uppfyllt.

  • 2.
    Amanda, Hugosson
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Carolina, Martinsson
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Konstruktion och design av duschredskap2014Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I denna rapport presenteras ett examensarbete som syftar till att ta fram idéer för en användarvänlig produkt, anpassad till dusch- och badrumsmiljöer som gör att äldre och funktionsnedsatta kan klara sig mer självständigt i hemmet. Arbetet har utförts tillsammans med uppdragsgivaren Jörgen Carlsson, produktchef på företaget Macro International AB (Macro) som tillverkar, utvecklar och säljer badrumslösningar med duschar och möbler. Examensarbetet har genomförts på Högskolan i Halmstad under våren 2014 och omfattar 15 högskolepoäng.

    Målet med projektet var att utifrån ett valt koncept utveckla en prototyp som passar till Macros nuvarande duschsortiment samt ta fram konstruktionsritningar för eventuell tillverkning av produkten. Produkten skulle vara lätt att montera för privatpersoner samt utstråla den känsla, enkelhet, personlighet och spänning som företaget strävar efter i alla sina produkter.

    Arbetet inleddes med en omfattande marknadsundersökning där tolkningen och resultatet av undersökningen tillsammans med uppdragsgivarens åsikter ledde till ett antal idéer att gå vidare med och utveckla. Två designmetodiker har kombinerats med en konstruktionsmetodik vilket har lett till ett slutligt resultat av ett duschredskap som kan användas som stöd i Macros duschar ”Skagen” och ”Fjord”. En prototyp av produkten tillverkades i Macros 3D-skrivare. Bildrenderingar och en monteringsfilm gjordes med hjälp av KeyShot 4, Catia V5 och Photoshop CS6. Även färdiga ritningar som kan användas vid en eventuell tillverkning är bifogade i rapporten.

  • 3.
    Andersson, Viktor
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Olsén, Martin
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Kilhus i plast: Omläggning av stålprodukt till produkt i plast2010Independent thesis Basic level (degree of Bachelor), 15 poäng / 22,5 hpOppgave
    Abstract [en]

    Abstract

    Our bachelor degree thesis was carried out in collaboration with Ivar Petterssons Järnmanufaktur AB in Smålandsstenar. We were asked to replace their wedge housing, used to fasten the wires to the power lines, with a similar structure in a plastic material. The idea for this project started with Ivar Petterssons Järnmanufaktur AB having problems with the casting quality that forced them to perform expensive tests on each of the wedge houses to ensure the quality. They are currently produced in China which is also a major drawback because it requires expensive long delivery times.

    The method we used is Fredy Olsson's Princip- and Primärkonstuktion (1995). We have consistently been in the project on so-called "broad front", which means that you create several sketches, ideas and changes in parallel, and then evaluates all. With this method we were able to largely concentrate on the current part of the project, rather than using the more time-consuming "trail and error" method, which is basically doing one idea at a time, and evaluate them one by one.

    At first we were very optimistic and thought we would be able to order form for the injection moulding process, but as the project progressed we found we were not certain that the product would hold and we were forced to present the solution as a concept that will require testing before it’s finished, and not a finished solution.The results we presented for Ivar Pettersssons Järnmanufaktur is a complete drawing on our primary solution, including the release angles. This is because when they decide to go forth with the project, it will be possible to produce a tool without having to make changes to the drawings. Temporary financial calculation shows that the savings may be realized around 1 300 000 SEK by switching to a plastic construction. However we have not been able to verify hours and therefore no cost estimates for the testing done in Sweden, so the actual amount of money saved is larger.

  • 4. Bellini, Anna
    et al.
    Gabrielson, Per
    Wiklund, Daniel
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK).
    Gunnarsson, L.
    Frictional properties of different austenitic stainless sheet surface topographies: Industrial trials at Alfa Laval2006Konferansepaper (Fagfellevurdert)
  • 5.
    Berglund, Johan
    et al.
    Institutionen för material- och tillverkningsteknik, Tillverkningsteknik, Chalmers tekniska högskola .
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Surface Finish and Roughness Measurement in Die and Mould Manufacturing2008Inngår i: Proceedings of the 2'nd Swedish Production Symposium, 2008, s. 385-391Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In die and mould manufacturing, the method used for quality control of finished surfaces is usually visual and tactile inspection of the finish, which is not easily quantifiable. In this study, an evaluation of the connection between surface finish appearance and measured surface roughness was carried out using scale-sensitive fractal analysis to find functional correlations and to determine suitable cut-off limits for functional data filtration. A selection of ball nose end mills in combination with two different tool steels (hardness 39 and 47 HRC) were used to manufacture surfaces that were measured. It was found that the method employed in this study for evaluating functional correlations and designing filters worked well. It was also found that there is a correlation between the surface roughness parameter Sq and the surface finish appearance and that this correlation is stronger in certain wavelengths on the surface.

  • 6.
    Berglund, Johan
    et al.
    Advanced Engineering, Sandvik Tooling, Olofström, Sweden.
    Wiklund, Daniel
    Forming Processes, Swerea IVF, Mölndal, Sweden.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    A Method for Visualization of Surface Texture Anisotropy in Different Scales of Observation2011Inngår i: Scanning, ISSN 0161-0457, E-ISSN 1932-8745, Vol. 33, nr 5, s. 325-331Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anisotropy of functional surfaces can in many practical cases significantly influence the surface function. Tribological contacts in sheet forming and engine applications are good examples. This article introduces and exemplifies a method for visualization of anisotropy. In a single graph, surface texture properties related to the anisotropy as a function of scale are plotted. The anisotropy graph can be used to explain anisotropy properties of a studied surface such as texture direction and texture strength at different scales of observation. Examples of milled steel surfaces and a textured steel sheet surface are presented to support the proposed methodology. Different aspects of the studied surfaces could clearly be seen at different scales. Future steps to improve filtering techniques and an introduction of length-scale analysis are discussed.

  • 7. Blaesild, Morgan
    et al.
    Alvtegen, Josefin
    Huledal, Oskar
    Produktutveckling med Svenska Brunalger2019Independent thesis Basic level (university diploma), 15 poäng / 22,5 hpOppgave
  • 8.
    Blixt, Lukas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Harmath, Laszlo
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Uttorkning av Betong2011Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
  • 9.
    Bournias-Varotsis, Alkaios
    et al.
    Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Friel, R. J.
    MAX IV Laboratory, Lund University, Lund, Sweden.
    Harris, Russell A.
    Mechanical Engineering, The University of Leeds, Leeds, United Kingdom.
    Engstrøm, Daniel S.
    Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Ultrasonic Additive Manufacturing as a form-then-bond process for embedding electronic circuitry into a metal matrix2018Inngår i: Journal of Manufacturing Processes, ISSN 1526-6125, Vol. 32, s. 664-675Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Additive Manufacturing (UAM) is a hybrid manufacturing process that involves the layer-by-layer ultrasonic welding of metal foils in the solid state with periodic CNC machining to achieve the desired 3D shape. UAM enables the fabrication of metal smart structures, because it allows the embedding of various components into the metal matrix, due to the high degree of plastic metal flow and the relatively low temperatures encountered during the layer bonding process. To further the embedding capabilities of UAM, in this paper we examine the ultrasonic welding of aluminium foils with features machined prior to bonding. These pre-machined features can be stacked layer-by-layer to create pockets for the accommodation of fragile components, such as electronic circuitry, prior to encapsulation. This manufacturing approach transforms UAM into a “form-then-bond” process. By studying the deformation of aluminium foils during UAM, a statistical model was developed that allowed the prediction of the final location, dimensions and tolerances of pre-machined features for a set of UAM process parameters. The predictive power of the model was demonstrated by designing a cavity to accommodate an electronic component (i.e. a surface mount resistor) prior to its encapsulation within the metal matrix. We also further emphasised the importance of the tensioning force in the UAM process. The current work paves the way for the creation of a novel system for the fabrication of three-dimensional electronic circuits embedded into an additively manufactured complex metal composite. © 2018 The Society of Manufacturing Engineers

  • 10.
    Bäck, Rickard
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Koncept för hållare till baklyktor2011Independent thesis Basic level (university diploma), 5 poäng / 7,5 hpOppgave
    Abstract [sv]

    I denna rapport presenteras olika koncept på hur utformningen av hållare till baklyktor kan se ut. Arbetet är ett samarbete mellan författaren och Specialkarosser AB.

    En mängd olika lösningar har utarbetats där det till slut uppenbarats fyra olika koncept på lösningar. Dessa olika lösningar har vägts mot varandra utifrån den metod som använts. Resultatet av dessa bedömningar blev ett koncept där tanken bakom lösningen är att utforma en kapsel som efterliknar det formspråk som finns på framlyktorna på lastbilar, samt att den ska kunna kombineras med flera likadana kapslar för att få fler lyktor.

  • 11.
    Bååth, Lars
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK).
    A method for simultaneously measuring the positions of more than one surface in metallurgic processes1994Patent (Annet (populærvitenskap, debatt, mm))
  • 12.
    Bååth, Lars
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK).
    A method to simultaneously measuring the position of more than one surface in metallurgical processes1997Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    A method for measuring the position of at least one surface in a metallurgical process which includes the steps of providing a metallurgical melt, the metallurgical melt including at least a metal portion and a slag layer, providing a signal generator for generating signals at a plurality of frequencies over a frequency band, and providing an antenna for receiving the signals generated by the signal generator and for transmitting circularly polarized radio waves at the plurality of frequencies over the frequency band. The invention further includes the steps of disposing the antenna adjacent the metallurgical melt, transmitting the circularly polarized radio waves from the antenna toward the metallurgical melt, the circularly polarized radio waves being transmitted by the antenna at the plurality of frequencies over the frequency band, receiving reflected images of the transmitted radio waves through the antenna, the received reflected images of the transmitted radio waves having a substantially opposite circular polarization from the transmitted circularly polarized radio waves, determining a phase displacement between the transmitted radio waves and the received reflected images of the transmitted radio waves, transforming the determined phase displacement from a frequency to a time plane, and determining from the time plane transform a position of at least one surface of at least one of the metal portion and the slag layer.

  • 13.
    Cabanettes, Frederic
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS). Halmstad Univ, Sch Business & Engn, SE-30118 Halmstad, Sweden..
    Rosén, Bengt Göran
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Topography changes observation during running-in of rolling contacts2014Inngår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 315, nr 1-2, s. 78-86Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The automotive industry and the design of engines are strongly ruled by performance and legislation demands. In the valve train, besides the main function (transformation of rotation to translation movements) to fulfill, new requirements in environmental demands and performance in terms of wear are leading to more and more detailed studies of the cams and rollers. Wear reduction studies for prolonging lifetime of these components require decreasing the scale of observation down to roughness. Among the different wear stages of a component, the running-in is a crucial period which will greatly influence the lifetime and performance of components. The aim of this paper is to analyze the topography variations observed during the running-in of a camshaft on a valve train rig test. A truck engine's camshaft is run under realistic conditions and 3D surfaces are measured before and after the test by using relocation techniques. By measuring the very same surfaces before and after the experiment, a deep analysis of the running-in effects on surfaces can be performed. 3D surface roughness parameters are used in parallel with new proposed methods of analysis. As a result, the mechanisms involved during running-in are emphasized and can be used for further simulations and optimization of the cam roller contact. (C) 2014 Elsevier B.V. All rights reserved.

  • 14.
    Cabanettes, Frédéric
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Cam Roller Contact: The topographical aspect2008Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The automotive industry and the design of engines are strongly ruled by performance and legislation demands. First order aspects defining the main functions of a component are well known and new challenges appear at a lower scale. Wear reduction is defined as a second order problem and requires decreasing the scale of observation of components down to roughness. This thesis work and its aim lie within the scope of wear improvements and are focused on the injection cam/roller contact of heavy duty diesel engines. In order to reach the aim several material and methods are used: a valve train rig test, roughness characterisation and different manufacturing processes. It is shown by experiments that the flank and nose of injection cams are specific areas with specific roughness (higher density of summits Sds) compared to the rest of the cam. The wear is characterized by rounded-off of summits (Ssc). From those results and since wear processes are strongly linked to the pressure generated between the mating surfaces, the development of a rough contact model is of great interest. An elastic rough contact model is implemented and improved later on by an elasto-plastic description of materials. The simulations are validated by a wear test and are used to rank the ability of surfaces (both cam and roller) to face wear problems. The ratio of plastically deformed peaks shows that the flank and nose of the cam are reacting badly to pressures. Additionally the rough contact allows ranking/optimization of different machining processes with respect to their expected functional contact performance. Future work will be to use such a model to choose a good combination of surfaces (cam and roller) in order to reduce wear.

  • 15.
    Cabanettes, Frédéric
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Evaluation of cam and roller surfaces and their manufacturing process by functional characterization2008Inngår i: Proceedings of the Swedish Production Symposium 2008, Stockholm: Swedish production symposium , 2008, , s. 7Konferansepaper (Fagfellevurdert)
  • 16.
    Cabanettes, Frédéric
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Tribological aspect of the surface topography variations for injection cams2008Inngår i: Proceedings of the NORDTRIB 2008 / [ed] Jaakko Kleemola and Arto Lehtovaara, Tampere: Tampere University Press, 2008, , s. 16Konferansepaper (Fagfellevurdert)
  • 17.
    Cabanettes, Frédéric
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Claret-Tournier, Julien
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK).
    Mohlin, Johan
    Finnveden Powertrain.
    Nilsson, P.-H.
    Volvo Technology Corporation.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Xiao, L.
    Volvo Powertrain Corporation.
    The evolution of surface topography of injection cams2009Inngår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 266, nr 5-6, s. 570-573Artikkel i tidsskrift (Fagfellevurdert)
  • 18.
    Cabanettes, Frédéric
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Mohlin, Johan
    Finnveden Powertrain, Lidköping, Sweden.
    Nilsson, Per Henrik
    Volvo Technology Corporation, Göteborg, Sweden.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Evaluation of cam surfaces by wear testing and functional characterization2008Inngår i: Synopses / 35th Leeds-Lyon Symposium on Tribology, Leeds: Leeds University , 2008Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Friction and wear are constant problems encountered in camshaft development. The contact between roller and cam is a mix of sliding and rolling which leads to a wide range of failure modes. The uniqueness of this contact is also due to variations all around the cam of a multitude of parameters such as load and radius. A previous study described surface topography as a function of cam shape. The different types of wear mechanisms are strongly linked to contact pressures which are also dependent on roughness. The aim of the paper is to develop a rough contact model which will be utilized as a tool to rank surfaces and their ability to face wear problems. In order to verify the tool, rough contact results are compared to roughness parameter variations due to wear produced in a cam roller rig test. The surface measurements used for this study are made by a non-contact light interferometer. The Greenwood-Williamson contact model has been developed in a deterministic way and the elasto-plastic behaviour of the material has been integrated to the model. The outputs of the simulation give a ranking of surfaces which is compared to their roughness variations due to wear. The study shows that the model developed is a reliable tool to rank and define surface quality since the results are correlated to wear. However, the results show as well some discrepancies which could be corrected in the future by integrating to the model two new features: a rough to rough contact including sliding between surfaces. This new model should be verified by an accurate experimentation using relocation between unworn and worn surfaces.

  • 19.
    Cabanettes, Frédéric
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Mohlin, Johan
    Finnveden Powertrain, Lidköping, Sweden.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Experimental study of cam/roller wear using advanced characterization tools for relocated surfaces2009Inngår i: Proceedings of the 3rd Swedish production symposium / [ed] Bengt-Göran Rosén, Swedish Production Academy , 2009, s. 197-203Konferansepaper (Fagfellevurdert)
  • 20.
    Campanini, D.
    et al.
    Department of Physics, Stockholm University, Stockholm, SE-106 91, Sweden.
    Diao, Zhu
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Tillämpad matematik och fysik (MPE-lab).
    Rydh, Andreas
    Department of Physics, Stockholm University, Stockholm, SE-106 91, Sweden.
    Raising the superconducting Tc of gallium: In situ characterization of the transformation of α -Ga into β -Ga2018Inngår i: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, nr 18, artikkel-id 184517Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Gallium (Ga) displays several metastable phases. Superconductivity is strongly enhanced in the metastable β-Ga with a critical temperature Tc=6.04(5)K, while stable α-Ga has a much lower Tc<1.2K. Here we use a membrane-based nanocalorimeter to initiate the transition from α-Ga to β-Ga on demand, as well as study the specific heat of the two phases on one and the same sample. The in situ transformation is initiated by bringing the temperature to about 10K above the melting temperature of α-Ga. After such treatment, the liquid supercools down to 232K, where β-Ga solidifies. We find that β-Ga is a strong-coupling type-I superconductor with Δ(0)/kBTc=2.00(5) and a Sommerfeld coefficient γn=1.53(4)mJ/molK2, 2.55 times higher than that in the α phase. The results allow a detailed comparison of fundamental thermodynamic properties between the two phases. © 2018 American Physical Society.

  • 21.
    Chandran, Sarath
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Maskinteknisk produktframtagning (MTEK).
    Abraham Mathews, Jithin
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Maskinteknisk produktframtagning (MTEK).
    Simulation and Optimization of CNC controlled grinding processes: Analysis and simulation of automated robot finshing process2016Independent thesis Advanced level (degree of Master (One Year)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Products with complicated shapes require superior surface finish to perform the intended function. Despite significant developments in technology, finishing operations are still performed semi automatically/manually, relying on the skills of the machinist. The pressure to produce products at the best quality in the shortest lead time has made it highly inconvenient to depend on traditional methods. Thus, there is a rising need for automation which has become a resource to remain competitive in the manufacturing industry.

    Diminishing return of trading quality over time in finishing operations signifies the importance of having a pre-determined trajectory (tool path) that produces an optimum surface in the least possible machining time. Tool path optimization for finishing process considering tool kinematics is of relatively low importance in the present scenario. The available automation in grinding processes encompass around the dynamics of machining.

    In this paper we provide an overview of optimizing the tool path using evolutionary algorithms, considering the significance of process dynamics and kinematics. Process efficiency of the generated tool movements are studied based on the evaluation of relative importance of the finishing parameters. Surface quality is analysed using MATLAB and optimization is performed on account of peak to valley height.

    Surface removal characteristics are analysed based on process variables that have the most likely impact on surface finish. The research results indicated that tool path is the most significant parameter determining the surface quality of a finishing operation. The inter-dependency of parameters were also studied using Taguchi design of experiments. Possible combinations of various tool paths and tool influencing parameters are presented to realize a surface that exhibits lowest errors.

  • 22.
    Dimkovski, Zlate
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    On Surface Topography of Cylinder Liners2008Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The frictional losses, oil consumption and emissions in internal combustion engines are in great extent controlled by the cylinder liner surface topography. This emphasises the importance of: investigating the liner’s topography by objectively characterising it, investigating its effects on the tribological function to gain a better understanding and improving its manufacturing. As a first attempt in this study to objectively characterise the liner surface, a traditional combination of Scanning Electron Microscope (SEM) images and roughness profiles was used. The groove and image parameters characteristic for liner topographies were extracted by applying specially developed algorithms and together with the standard parameters served to study wear on liners of diesel and petrol engines. An experiment was designed to improve the liners’ manufacturing by varying of the honing process parameters and oil flow simulations were run to study the influence of the characteristics of the manufactured surfaces on their function. The results suggested that reducing the base honing pressure and increasing the plateau honing time gave the best surface with smoother plateaux, summits of higher density and milder slopes, more but smaller islands and shallower valleys. The potentials of fast acquiring and containing 3D data of the interference measurements were utilised to overcome the encountered problems in the usage of the combination of profile and SEM measurements and to enable automatic quality control of the cylinder liner surfaces. In the efforts to examine the influence of the surface properties on liner’s function, the extent of blechmantel (cold work material) removal was estimated from 3D measurements of run liners in engine tests. For characterising this feature, algorithms were developed and implemented and it was found that the most of the blechmantel is still left on the liner pointing that it plays a minor role on wear.

  • 23.
    Dimkovski, Zlate
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Surfaces of Honed Cylinder Liners2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Cylinder liner surfaces are often on the agenda of engine developers because of their large influence on the frictional losses, oil consumption and emissions of internal combustion engines. Improving the liner function involves not only manufacturing new surfaces and checking their function but also characterising them as a necessary intermediate step for better understanding of the changes made. In the manufacturing of the liners, honing is a well adapted and widely used finishing process and along with the characterisation and function has been the subject of studies in this thesis. Regarding the liner’s function, three phenomena were monitored: wear, friction and oil passage rate (correlated with engine’s oil consumption). The first one was studied experimentally while the other two were simulated. Only the interactions with the twin land oil control ring were simulated as it has the greatest influence on the control of friction and oil consumption of all other rings. In the mid-stroke region of truck engine liners, the presence of axial wear scratches was observed and their relation with the removal of the cold worked material (“Blechmantel”) folded inside the deep honing grooves was investigated. Algorithms were developed for estimating the extent of Blechmantel, revealing that most of it remained on the surface whereas the engines still performed well. Other algorithms for characterising honing angle, balance of honing texture, width, height, distance between honing grooves/axial wear scratches, etc were developed for quicker and more objective inspection of unworn and worn surfaces from 3D interference measurements. Based on such 3D measurements, the algorithms were incorporated in a characterisation tool enabling rating of the surfaces and determining the number of measurements necessary to achieve stable roughness parameter values. In addition, it was found that interference measurements are more suitable for quantification of the deposits on the worn truck liner surfaces compared with scanning electron microscope measurements. The lubrication and friction of flat oil control ring lands and differently slide honed surfaces of truck liners were simulated. Friction mean effective pressure and oil passage rate were calculated for each surface showing in each case a reduction for the surfaces with smoother plateaus and smaller valleys. Such a liner surface was finished by using a low base honing pressure and a longer plateau honing time. In a car engine, the influence of different liner surfaces, ring land widths and tensions was examined by running simulations. The results suggest that a considerably improved function can be achieved if the ring land width and tension are reduced whereby the differences between the liner surfaces would reduce.

  • 24.
    Dimkovski, Zlate
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Anderberg, Cecilia
    Volvo Power Train Corp., Volvo Group, Göteborg, Sweden.
    Cabanettes, Frédéric
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Löfgren, Hans
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Rosén, B.-G.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Influence of Different Cylinder Liner Surfaces on Their Performance with the Twin Land Oil Control Ring in a Car Engine2011Inngår i: Proceedings of the 13th International Conference on Metrology and Properties of Engineering Surfaces, 2011Konferansepaper (Fagfellevurdert)
  • 25.
    Dimkovski, Zlate
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Anderberg, Cecilia
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Ohlsson, Robert
    Volvo Power Train Corp., Volvo Group, Göteborg, Sweden.
    Thomas, Tom R.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Quantification of Blechmantel Effect on Wear of Cylinder Bore Microtopography2008Inngår i: Proceedings of the 13th Nordic Symposium on Tribology, Nordtrib 2008, Tampere: Tampere University Press, 2008, s. 13-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The presence of cold work material (blechmantel) smeared out on cylinder liners by faulty honing is undesirable as it seals the oil-bearing honing grooves. It is also believed to correlate with increased bore wear, presumably due to its loosening and together with the carbon build-up from the piston’s top land form an increased quantity of abrasive particles. An attempt has been made to estimate the extent of removal of blechmantel for different wear regimes present at the middle and top region (near the top dead centre) of the liner surface using the unworn bottom region as a reference for comparison. A number of truck cylinder liners were axially sectioned after varying periods of engine running under similar conditions of load, engine speed and lubrication. 3D surface measurements were taken at the three regions and a range of standard parameters was extracted. Combining the profile and image analysis, an algorithm was developed to identify and quantify the blechmantel covering the grooves that is most likely to break and act as abrasive wear particles and at the same time it represents the part of blechmantel which covers the most of the surface. It was found out that a mere portion of the blechmantel from the middle and bottom section was removed, while the blechmantel from the top section was greatly removed and thereby it represents one of the possible causes for wear. Axial wear scratches more emphasized on the thrust side of the liner were observed not only through the whole stroke area, but also in the bottom region. The fact that the most of the blechmantel is not removed from the running surface of the liner (except for the very small portion of the polished areas at the dead centres), points out that the blechmantel plays only a minor role on wear of the cylinder liner surfaces.

  • 26.
    Dimkovski, Zlate
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Cabanettes, Frédéric
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Löfgren, Hans
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Anderberg, Cecilia
    Volvo Cars.
    Ohlsson, Robert
    Volvo Powertrain.
    Rosén, Bengt-Göran
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Optimisation of Cylinder Liner Surface Finish by Slide Honing2012Inngår i: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 226, nr 4, s. 575-584Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cylinder liner surface finish controls the frictional losses, oil consumption, and emissions of internal combustion engines to a large extent. In order to minimize such losses, it is important to optimize the liner surface topography by a consistent and more productive finishing process such as slide honing. This process employs diamond abrasives and has been recently introduced in the automotive industry. In this study, its potentials are explored, especially the winning combination of its key process parameters: the base honing pressure and plateau honing time that would yield an optimal liner surface finish. A number of truck engine liners were slide-honed by using different process parameters, samples of the liners were cut, and three-dimensional (3D) surface measurements were taken on a white light interferometer. Then, among others, the (deep honing) groove parameters, specific for liner surfaces, were computed from the measurements for building a large database for comparison and correlation. By simulating the contact and fluid mechanics between the measured liner topographies and a twin land oil control ring under mixed lubrication conditions, the friction mean effective pressure and oil passage rate for a range of engine speeds were calculated. These two parameters represent the liner's function associated with the engine's friction and oil consumption respectively. The results show that the lowest friction and oil flow are highly correlated with surfaces having smoother plateaus and smaller valleys, finished by using lower base honing pressure and longer plateau honing time. High correlations between the 3D roughness parameters were also found, enabling the selection and use of more stable and robust parameters in the quality control of the liner's surface finish. © IMechE 2012.

  • 27.
    Engkvist, Gustav
    et al.
    Högskolan i Halmstad.
    Hansson, Sebastian
    Högskolan i Halmstad.
    FE-modellering av hjullast på sandwichpanel2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This bachelor thesis in mechanical engineering was performed during the spring2015 in collaboration with Composite Consulting Group in Laholm. TheComposites Consulting Group works mainly with design and details of differentcomposite projects, their main area is FE-calculations, 3D-modelling andmechanical tests with composite materials.The aim of this bachelor thesis was to simplify the calculation process of solidmechanics for sandwich panels by simulation with computer software. The goalwas to decrease the time for the design and calculation process of the constructionand the cost of the practical tests. Our task was to build a static three dimensionalmodel with the computer software Abaqus, where the result should correspondwith the practical pressure tests in laboratory.The project started with collection of material data from Composites ConsultingGroup and by learning the software Abaqus, simultaneously a specification wasdeveloped in corporation with the company. Later on, a static wheel pressuremodel in the software Abaqus was produced which simulated the behavior of thesandwich panel during static wheel-pressure by a pallet truck. The results from thewheel-pressure model were verified with the practical tests.The project led to a static three dimensional wheel- contact model with thesoftware Abaqus to calculate complex wheel-contact problems on sandwichpanels. The wheel-contact model corresponded to the practical test results. Thecontact model with Abaqus enabled faster and more efficient design anddevelopment process of new sandwich panels. It also provided better analysis ofthe sandwich panels’ behavior during wheel- contact loading.

  • 28.
    Eriksson, Carl-Johan
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Erlingsson, Jonas
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    FRP i brokonstruktion: -varför används FRP inte i Sverige2015Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    FRP stands for Fiber Reinforced Polymer. FRP materials have yet to be introduced inbridge construction in Sweden. Composite materials can through combined componentsand manufacturing processes be tailored to fit advanced bridge designs. FRP materials arestrong, durable and of low weight. FRP materials give the superstructure reduced weightand are therefore a suitable alternative for industrial prefabrication. This report shows thatFRP materials are possible to use in bridge construction. With the introduction of a specificEurocode we are confident that FRP materials will become a competitive alternative inbridge construction in Sweden in the future.

  • 29.
    Flys, Olena
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS). RISE Research Institutes of Sweden, Borås, Sweden.
    Jarlemark, Per
    RISE Research Institutes of Sweden, Borås, Sweden.
    Petronis, Sarunas
    RISE Research Institutes of Sweden, Borås, Sweden.
    Patrik, Stenlund
    RISE Research Institutes of Sweden, Borås, Sweden.
    Rosén, Bengt Göran
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    Applicability of characterization techniques on fine scale surfaces2018Inngår i: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 6, nr 3, artikkel-id 034015Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, several surface topographies typical for dental implants were evaluated by different measurement techniques. The samples were prepared by machine turning, wet chemical etching and electrochemical polishing of titanium discs. The measurement techniques included an atomic force microscope (AFM), coherence scanning interferometer (CSI) and a 3D stereo scanning electron microscope (SEM). The aim was to demonstrate and discuss similarities and differences in the results provided by these techniques when analyzing submicron surface topographies. The estimated surface roughness parameters were not directly comparable since the techniques had different surface spatial wavelength band limits. However, the comparison was made possible by applying a 2D power spectral density (PSD) function. Furthermore, to simplify the comparison, all measurements were characterized using the ISO 25178 standard parameters. Additionally, a Fourier transform was applied to calculate the instrument transfer function in order to investigate the behavior of CSI at different wavelength ranges. The study showed that 3D stereo SEM results agreed well with AFM measurements for the studied surfaces. Analyzed surface parameter values were in general higher when measured by CSI in comparison to both AFM and 3D stereo SEM results. In addition, the PSD analysis showed a higher power spectrum density in the lower frequency range 10−2–10−1 µm−1 for the CSI compared with the other techniques. © 2018 IOP Publishing Ltd

  • 30.
    Friel, R. J.
    Loughborough University, Loughborough, United Kingdom.
    13 - Power ultrasonics for additive manufacturing and consolidating of materials2015Inngår i: Power Ultrasonics: Applications of High-Intensity Ultrasound / [ed] Gallego-Juarez, Juan A. & Graff, Karl F., Oxford: Woodhead Publishing Limited, 2015, s. 313-335Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    This chapter explores the ultrasonic additive manufacturing (UAM) advanced solid-state metal additive/subtractive manufacturing process that combines ultrasonic welding and computer numerical control milling to fabricate solid metal components, layer-by-layer, from metal foils. The chapter will discuss the three key abilities of UAM: complicated geometries, dissimilar material bonding, and object embedment. The combination of these three key abilities places UAM as a most attractive method with which to create metal matrix-based freeform smart structures for high-value engineering applications. © 2015 Elsevier Ltd. All rights reserved.

  • 31.
    Friel, R. J.
    et al.
    The Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Harris, R. A.
    The Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Ultrasonic additive manufacturing – A hybrid production process for novel functional products2013Inngår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 6, s. 35-40Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Additive Manufacturing (UAM), or Ultrasonic Consolidation as it is also referred, is a hybrid form of manufacture, primarily for metal components. The unique nature of the process permits extremely novel functionality to be realised such as multi-material structures with embedded componentry. UAM has been subject to research and investigation at Loughborough University since 2001. This paper introduces UAM then details a number of key findings in a number of areas that have been of particular focus at Loughborough in recent years. These include; the influence of pre-process material texture on interlaminar bonding, secure fibre positioning through laser machined channels, and freeform electrical circuitry integration. © 2013 The Authors.

  • 32.
    Friel, R. J.
    et al.
    The Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Harris, R. A.
    The Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Ultrasonic additive manufacturing research at Loughborough University2012Inngår i: Proceedings of the Twenty Third Annual International Solid Freeform Fabrication Symposium – An Additive Manufacturing Conference, Austin, Texas, USA, 6-8 August 2012 / [ed] D. Bourell, R. H. Crawford, C. C. Seepersad, J. J. Beaman, & H. Marcus, 2012, s. 354-363Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Additive Manufacturing (UAM) has been subject to research and investigation at Loughborough University since 2001. In recent years, three particular areas of significant focus have been:

    • The influence of pre-process material texture on interlaminar bonding.

    • Secure fibre positioning through laser machined channels.

    • Freeform electrical circuitry integration.

    This paper details the key findings and a number of conclusions from these work areas. The results of this work have led to the further research and developmental applications for the UAM technology.

  • 33.
    Friel, R. J.
    et al.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Johnson, K. E.
    Solidica Inc., Ann Arbor, MI, USA.
    Dickens, P. M.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Harris, R. A.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    The effect of interface topography for Ultrasonic Consolidation of aluminium2010Inngår i: Journal of Materials Science and Engineering: A, ISSN 2161-6213, Vol. 527, nr 16-17, s. 4474-4483Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Consolidation (UC) is an additive manufacturing technology which is based on the sequential solid-state ultrasonic welding of metal foils. UC presents a rapid and adaptive alternative process, to other metal-matrix embedding technologies, for 'smart' metal composite material production. A challenge that exists however relates to optimising, for bond density and plastic flow, the interlaminar textures themselves that serve as the contact surfaces between the foils.UC employs a sonotrode connected to a transducer to exude ultrasonic energy into the metal foil being sequentially deposited. This sonotrode to metal contact imparts a noteworthy topology to the processed metals surface that in turn becomes the crucial substrate topology of the subsequent layers deposition. This work investigated UC processed Al 3003 samples to ascertain the effect of this imparted topology on subsequent layer deposition. Surface and interlaminar topology profiles were characterised using interferometry, electron and light microscopy. The physical effect of the topology profiles was quantified via the use of peel testing.The imparted topology profile was found to be of fundamental significance to the mechanical performance and bond density achieved within the bulk laminate during UC. The UC process parameters and sonotrode topology performed a key role in modifying this topology profile. The concept of using a specifically textured sonotrode to attain desired future smart material performance via UC is proposed by the authors. © 2010 Elsevier B.V.

  • 34.
    Friel, R. J.
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Masurtschak, Simona
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Harris, Russell A.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Enabling dissimilar fibre embedding and explicit fibre layout in ultrasonic consolidation2010Inngår i: Proceedings of the 21st International Conference on Adaptive Structures and Technologies 2010, University Park, PA: Curran Associates, Inc., 2010, s. 303-310Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Consolidation (UC) is a manufacturing technique based on the ultrasonic metal welding of a sequence of metal foils which are bonded to one another in a layer by layer manner. It combines the ability of additive and subtractive manufacturing techniques to create complex three-dimensional shapes. Due to moderate applied pressures and the relatively low temperatures experienced by a sample during manufacture, UC operates as a solid-state process. UC could potentially enable the fabrication of smart structures via integration of sensor, actuator and reinforcement fibres within a single metal matrix. Previous issues with the optimal placement of fibres directly between foils during UC have been identified. Also, different types of integrated fibres require different UC process conditions and thus present complications when integrating them in combination. To truly exploit the full potential of UC for smart structure capabilities it is envisioned that a high volume fraction of dissimilar fibres are required to be integrated together within a single metal matrix structure. Research on a new method to consolidate fibres securely and more accurately during UC is presented. Channels created prior to UC within metal matrix composites are investigated as a method to aid the embedding of high volume fractions of different fibres in unison without damage. Initial research using a 200 W fibre laser as an enabling tool to create channels of specific geometry onto a previously UC processed surface is detailed. The research verifies that controlled channelling on a UC surface is possible and that channel geometry is dependent on: laser traverse speed, laser beam power, and shroud gas flow rate. © (2010) by the International Conference on Adaptive Structures and Technologies (ICAST).

  • 35.
    Gibson, Myles
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    The Heat Treatment of Nickel Titanium - An investigation Using Taguchi's Method of Optimisation2015Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
  • 36.
    Goulas, Athanasios
    et al.
    Wolfson School of Mechanical, Electrical & Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Binner, Jon G.P.
    College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom.
    Harris, Russell A.
    Mechanical Engineering, University of Leeds, Leeds, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical, Electrical & Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Assessing extraterrestrial regolith material simulants for in-situ resource utilisation based 3D printing2017Inngår i: Applied Materials Today, ISSN 2352-9407, Vol. 6, s. 54-61Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This research paper investigates the suitability of ceramic multi-component materials, which are found on the Martian and Lunar surfaces, for 3D printing (aka Additive Manufacturing) of solid structures. 3D printing is a promising solution as part of the cutting edge field of future in situ space manufacturing applications.

    3D printing of physical assets from simulated Martian and Lunar regolith was successfully performed during this work by utilising laser-based powder bed fusion equipment. Extensive evaluation of the raw regolith simulants was conducted via Optical and Electron Microscopy(SEM), Visible–Near Infrared/Infrared (Vis–NIR/IR) Spectroscopy and thermal characterisation via Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The analysis results led to the characterisation of key properties of these multi-component ceramic materials with regard to their processability via powder bed fusion 3D printing.

    The Lunar and Martian simulant regolith analogues demonstrated spectral absorbance values of up to 92% within the Vis–NIR spectra. Thermal analysis demonstrated that these materials respond very differently to laser processing, with a high volatility (30% weight change) for the Martian analogue as opposed to its less volatile Lunar counterpart (<1% weight change). Results also showed a range of multiple thermal occurrences associated with melting, glass transition and crystallisation reactions. The morphological features of the powder particles are identified as contributing to densification limitations for powder bed fusion processing.

    This investigation has shown that – provided that the simulants are good matches for the actual regoliths – the lunar material is a viable candidate material for powder bed fusion 3D printing, whereas Martian regolith is not. © 2016 Elsevier Ltd

  • 37.
    Goulas, Athanasios
    et al.
    Wolfson School of Mechanical, Electrical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Engstrøm, Daniel S.
    Wolfson School of Mechanical, Electrical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Friel, Ross J.
    Wolfson School of Mechanical, Electrical & Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Harris, Russell A.
    Mechanical Engineering, University of Leeds, Leeds, United Kingdom.
    Investigating the additive manufacture of extra-terrestrial materials2016Inngår i: Proceedings of the 2016 Annual International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference / [ed] Bourell, D. L., 2016, s. 2271-2281Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Powder Bed Fusion (PBF) additive manufacturing process category, consists of a group of key enabling technologies allowing the fabrication of both intrinsic and complex structures for a series of applications, including aerospace and astronautics. The purpose of this investigation was to explore the potential application of in-space additive manufacturing/3D printing, for onsite fabrication of structures and parts, using the available extra-terrestrial natural resources as feedstock. This study was carried out by using simulants of terrestrial origin, mimicking the properties of those respective materials found extra-terram (in space). An investigation was conducted through material characterisation, processing and by powder bed fusion, and resultant examination by analytical techniques. The successful realisation of this manufacturing approach in an extra-terrestrial environment could enable a sustainable presence in space by providing the ability to build assets and tools needed for long duration/distance missions in deep space.

  • 38.
    Goulas, Athanasios
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    3D printing with moondust2016Inngår i: Rapid prototyping journal, ISSN 1355-2546, E-ISSN 1758-7670, Vol. 22, nr 6, s. 864-870Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose - The purpose of this paper is to investigate the effect of the main process parameters of laser melting (LM) type additive manufacturing (AM) on multi-layered structures manufactured from JSC-1A Lunar regolith (Moondust) simulant powder. Design/methodology/approach - Laser diffraction technology was used to analyse and confirm the simulant powder material particle sizes and distribution. Geometrical shapes were then manufactured on a Realizer SLM™ 100 using the simulant powder. The laser-processed samples were analysed via scanning electron microscopy to evaluate surface and internal morphologies, X-ray fluorescence spectroscopy to analyse the chemical composition after processing, and the samples were mechanically investigated via Vickers micro-hardness testing. Findings - A combination of process parameters resulting in an energy density value of 1.011 J/mm2 allowed the successful production of components directly from Lunar regolith simulant. An internal relative porosity of 40.8 per cent, material hardness of 670 ±11 HV and a dimensional accuracy of 99.8 per cent were observed in the fabricated samples. Originality/value - This research paper is investigating the novel application of a powder bed fusion AM process category as a potential on-site manufacturing approach for manufacturing structures/components out of Lunar regolith (Moondust). It was shown that this AM process category has the capability to directly manufacture multi-layered parts out of Lunar regolith, which has potential applicability to future moon colonization. © Emerald Group Publishing Limited.

  • 39.
    Goulas, Athanasios
    et al.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Harris, Russell A.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Friel, Ross J.
    Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Additive manufacturing of physical assets by using ceramic multicomponent extra-terrestrial materials2016Inngår i: Additive Manufacturing, ISSN 2214-8604, Vol. 10, s. 36-42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Powder Bed Fusion (PBF) is a range of advanced manufacturing technologies that can fabricate three-dimensional assets directly from CAD data, on a successive layer-by-layer strategy by using thermal energy, typically from a laser source, to irradiate and fuse particles within a powder bed.

    The aim of this paper was to investigate the application of this advanced manufacturing technique to process ceramic multicomponent materials into 3D layered structures. The materials used matched those found on the Lunar and Martian surfaces. The indigenous extra-terrestrial Lunar and Martian materials could potentially be used for manufacturing physical assets onsite (i.e., off-world) on future planetary exploration missions and could cover a range of potential applications including: infrastructure, radiation shielding, thermal storage, etc.

    Two different simulants of the mineralogical and basic properties of Lunar and Martian indigenous materials were used for the purpose of this study and processed with commercially available laser additive manufacturing equipment. The results of the laser processing were investigated and quantified through mechanical hardness testing, optical and scanning electron microscopy, X-ray fluorescence spectroscopy, thermo-gravimetric analysis, spectrometry, and finally X-ray diffraction.

    The research resulted in the identification of a range of process parameters that resulted in the successful manufacture of three-dimensional components from Lunar and Martian ceramic multicomponent simulant materials. The feasibility of using thermal based additive manufacturing with multi-component ceramic materials has therefore been established, which represents a potential solution to off-world bulk structure manufacture for future human space exploration. © 2016 Elsevier B.V.

  • 40.
    Höglund, Andreas
    et al.
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    Sivertsson, Olof
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    qbits: Kombinerar användning och förvaring av bits2011Independent thesis Basic level (university diploma), 15 poäng / 22,5 hpOppgave
    Abstract [en]

    Aren’t you tired of never finding stuff? Take a bits as example, do you store these lose in your toolbox or carpenter belt? What if you could have it all accessible and assembled in a tool, always at arm’s reach?

    Today bits are used together with electric screwdrivers and handheld screwdrivers in a greater spread. For these different types of storage, from pure storage boxes to complex tools with storage built in, exist. The professional craftsmen commonly use some kind of box where the bits can be stored. Even so they tend to store their bits loose in a carpenter belt or toolbox, since they want the speed and accessibility of carpenter belt over the storage box’s tidiness.

    The project was started in the fall of 2010 and a referents group was early put together to ensure that the developed product became as user-friendly and attractive as possible. The referents group contained our target group, professional craftsmen and other competent persons within the field. In cooperation with the referents group a needs and wants list was put together to make sure that the product satisfice the need.

    The lack of a good storage solution has led to a unique product which suit for both usage and storage of bits. Through combining the carpenter belt and the storage box speed, accessibility and tidiness is obtained. A solution suggestion with a prototype was created which satisfied the set needs and wants. The solution was presented for the referents group and the response was good but improvements suggestions were given. These were taken and work began on a new version.

    The result became a new product, qbits, the unique tool which combine usage and storage of bits.

  • 41.
    Johansson, Ohlsson, Nilsson, Andreas, Johan, Arvid
    Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET).
    PlusTak2010Student paper other, 15 poäng / 22,5 hpOppgave
    Abstract [en]

    Today´s roofing of dwelling houses is a very time consuming procedure, which includes a lot of different steps on the construction site. Not only does it cost a lot of money, but often do problems with rot and mold occur in the attics of houses today.

     

    The use of prefabricated modules has seen a great breakthrough in the field of construction of dwelling houses; at least when it comes to foundations and walls, where this type of approach makes the construction process way more efficient. What no one previous has succeeded to develop is a corresponding system for roofs that meets the demands of a dwelling house. Accordingly the goal of PlusTak has been to come up with a proper module system for roofing of dwelling houses, where the roofing is completed to meet the demands of the Scandinavian market.

     

    During the project a lot of effort has been put into customer contacts and the usability of the product, as well in the manufacturing process as on the construction site. This development has gone hand in hand with several practical tests and tryouts. The project group has also participated in the use of PlusTak at various construction sites this spring, to get a better view of what could be further developed with the product. The outcome is a complete roofing system which is almost entirely prefabricated, and only requires a few hours on the construction site for completion of a fully weather protected roof. PlusTak is a very flexible system which is perfectly suitable for different house and roof types, and fits almost any roof pitch. The visible layer of the roof is available both as a classic seamed tin roof and with traditional tiles. Thanks to the great capability of insulation within the PlusTak system it suits the modern energy efficient houses perfectly. Moreover the insulation layer of the roof is placed in the outer roof, which eliminates the problems concerning condensation that occurs in weather and temperature changes, which has been a growing issue lately.

    Thus, PlusTak offers a cost-effective roof system of the as well as it provides a totally carefree ownership.

     

    An intense marketing campaign has been conducted through several channels during the development of the product. PlusTak was presented with great success at Nordbyggmässan in Stockholm, the biggest construction fair in Scandinavia, in March 2010. This was right after the product became patent pending. PlusTak has currently sold for over one million SEK and has been quoted on request for over 40 million SEK.  The annual market in Sweden corresponds to over two billion, despite the current recession. The project group is counting on taking over 2-10% of that market within a period of five years.

  • 42.
    Johansson, Staffan
    et al.
    Volvo Group Trucks Technology, Vehicle Engineering, Gothenburg, Sweden.
    Nilsson, Per H.
    Volvo Group Trucks Technology, Advanced Technology & Research, Gothenburg, Sweden.
    Ohlsson, Robert
    Volvo Group Trucks Technology, Powertrain Engineering, Gothenburg, Sweden.
    Rosén, Bengt Göran
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Rydberglaboratoriet för tillämpad naturvetenskap (RLAS).
    A Novel Approach to Reduction of Frictional Losses in a Heavy-Duty Diesel Engine by Reducing the Hydrodynamic Frictional Losses2017Inngår i: Advances in Tribology, ISSN 1687-5915, E-ISSN 1687-5923, Vol. 2017, s. 1-17, artikkel-id 9240703Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An important parameter in the reduction of fuel consumption of heavy-duty diesel engines is the Power Cylinder Unit (PCU); the PCU is the single largest contributor to engine frictional losses. Much attention, from both academia and industry, has been paid to reducing the frictional losses of the PCU in the boundary and mixed lubrication regime. However, previous studies have shown that a large portion of frictional losses in the PCU occur in the hydrodynamic lubrication regime. A novel texturing design with large types of surface features was experimentally analyzed using a tribometer setup. The experimental result shows a significant reduction of friction loss for the textured surfaces. Additionally, the textured surface did not exhibit wear. On the contrary, it was shown that the textured surfaces exhibited a smaller amount of abrasive scratches on the plateaus (compared to the reference plateau honed surface) due to entrapment of wear particles within the textures. The decrease in hydrodynamic friction for the textured surfaces relates to the relative increase of oil film thickness within the textures. A tentative example is given which describes a method of decreasing hydrodynamic frictional losses in the full-scale application. © 2017 Staffan Johansson et al.

  • 43.
    Lund, Per
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Jakobsson, Peter
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Detaljerad FE-modellering2015Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete beskriver undersökningen av kärnmaterial i en sandwichpanel under belastning. Arbetet har utförts tillsammans med CCG i Laholm, Sverige. Kärnmaterialen lämpar sig vid design av sandwichpaneler på grund av sin låga vikt och sin förmåga att klara av högt tryck. Då materialet uppvisar ett ickelinjärt beteende skapar det problem vid design av sandwichpaneler och leder till att materialsammansättningarna tillverkas konservativa mot verkligheten. Projektet har gått ut på reducera designprocessen genom att bygga upp och simulera materialmodeller i programvaran ABAQUS för att kunna analysera och förutse materialets beteende. Resultaten har presenterats i kraft- och förskjutningsdiagram samt visualiseringar och har försvarats med hjälp av teorier för kontaktmekanik samt matematik. Projektet har utförts på ett vetenskapligt sätt där hypotes verifieras mot teori för att sedan verifieras i experiment, allt för att säkerställa resultatet.

  • 44.
    Masurtschak, S.
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Gillner, A.
    Fraunhofer Institute for Laser Technology, Aachen, Germany.
    Ryll, J.
    Fraunhofer Institute for Laser Technology, Aachen, Germany.
    Harris, R. A.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Fiber laser induced surface modification/manipulation of an ultrasonically consolidated metal matrix2013Inngår i: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 213, nr 10, s. 1792-1800Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic Consolidation (UC) is a manufacturing technique based on the ultrasonic joining of a sequence of metal foils. It has been shown to be a suitable method for fiber embedment into metal matrices. However, integration of high volume fractions of fibers requires a method for accurate positioning and secure placement to maintain fiber layouts within the matrices. This paper investigates the use of a fiber laser for microchannel creation in UC samples to allow such fiber layout patterns. A secondary goal, to possibly reduce plastic flow requirements in future embedding processes, is addressed by manipulating the melt generated by the laser to form a shoulder on either side of the channel. The authors studied the influence of laser power, traverse speed and assist gas pressure on the channel formation in aluminium alloy UC samples. It was found that multiple laser passes allowed accurate melt distribution and channel geometry in the micrometre range. An assist gas aided the manipulation of the melted material. © 2013 Elsevier B.V. All rights reserved.

  • 45.
    Masurtschak, S.
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Gillner, A.
    Fraunhofer Institute for Laser Technology, Aachen, Germany.
    Ryll, J.
    Fraunhofer Institute for Laser Technology, Aachen, Germany.
    Harris, R. A.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Laser-Machined Microchannel Effect on Microstructure and Oxide Formation of an Ultrasonically Processed Aluminum Alloy2015Inngår i: Journal of engineering materials and technology, ISSN 0094-4289, E-ISSN 1528-8889, Vol. 137, nr 1, artikkel-id 011006Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic consolidation (UC) has been proven to be a suitable method for fiber embedment into metal matrices. To aid successful embedment of high fiber volumes and to ensure their accurate positioning, research on producing microchannels in combination with adjacent shoulders formed by distribution of the melt onto unique UC sample surfaces with a fiber laser was carried out. This paper investigated the effect of the laser on the microstructure surrounding the channel within an Al 3003-H18 sample. The heat input and the extent of the heat-affected zone (HAZ) from one and multiple passes was examined. The paper explored the influence of air, as an assist gas, on the shoulders and possible oxide formation with regards to future bonding requirements during UC. The authors found that one laser pass resulted in a keyhole-shaped channel filled with a mixture of aluminum and oxides and a symmetrical HAZ surrounding the channel. Multiple passes resulted in the desired channel shape and a wide HAZ which appeared to be an eutectic microstructure. The distribution of molten material showed oxide formation all along the channel outline and especially within the shoulder. © 2015 by ASME.

  • 46.
    Masurtschak, Simona
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    Harris, Russell A.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom.
    New concept to aid efficient fibre integration into metal matrices during ultrasonic consolidation2017Inngår i: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 231, nr 7, s. 1105-1115Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ultrasonic consolidation has been shown to be a viable metal-matrix-based smart composite additive layer manufacturing process. Yet, high quantity fibre integration has presented the requirement for a method of accurate positioning and fibre protection to maintain the fibre layout during ultrasonic consolidation. This study presents a novel approach for fibre integration during ultrasonic consolidation: channels are manufactured by laser processing on an ultrasonically consolidated sample. At the same time, controlled melt ejection is applied to aid accurate fibre placement and simultaneously reducing fibre damage occurrences. Microscopic, scanning electron microscopic and energy dispersive X-ray spectroscopic analyses are used for samples containing up to 10.5% fibres, one of the highest volumes in an ultrasonically consolidated composite so far. Up to 98% of the fibres remain in the channels after consolidation and fibre damage is reduced to less than 2% per sample. This study furthers the knowledge of high volume fibre embedment via ultrasonic consolidation for future smart material manufacturing. © Institution of Mechanical Engineers.

  • 47.
    Millman, Stuart
    et al.
    British Steel plc Moorgate Rotherham, United Kingdom.
    Bååth, L.B.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Maskinteknisk produktframtagning (MTEK).
    Malmberg, Donald
    MEFOS, Foundation for Metallurgical Research, Luleå, Sweden.
    Radio-wave inferometry for BOS slag control2001Rapport (Fagfellevurdert)
    Abstract [en]

    The aim of the project is to use radio-wave interferometry to determine the BOF slag and metal heights in both a quiescent and a blowing BOS convertor. The hydrodynamics of the slag/metal emulsion and 1, 2 and possibly 3D representations of slag and metal movements during the blowing phase will be made. Process factors such as vessel shape, lance movements, bath agitation, flux/ore additions and fume generation will be considered.

  • 48.
    Monaghan, T.
    et al.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Capel, A. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Christie, S. D.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Harris, R. A.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Friel, R. J.
    Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom.
    Solid-state additive manufacturing for metallized optical fiber integration2015Inngår i: Composites. Part A, Applied science and manufacturing, ISSN 1359-835X, E-ISSN 1878-5840, Vol. 76, s. 181-193Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The formation of smart, Metal Matrix Composite (MMC) structures through the use of solid-state Ultrasonic Additive Manufacturing (UAM) is currently hindered by the fragility of uncoated optical fibers under the required processing conditions. In this work, optical fibers equipped with metallic coatings were fully integrated into solid Aluminum matrices using processing parameter levels not previously possible. The mechanical performance of the resulting manufactured composite structure, as well as the functionality of the integrated fibers, was tested. Optical microscopy, Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) analysis were used to characterize the interlaminar and fiber/matrix interfaces whilst mechanical peel testing was used to quantify bond strength. Via the integration of metallized optical fibers it was possible to increase the bond density by 20–22%, increase the composite mechanical strength by 12–29% and create a solid state bond between the metal matrix and fiber coating; whilst maintaining full fiber functionality. © 2015 The Authors. Published by Elsevier Ltd.

  • 49.
    Muzaffar, Othman Abdulla
    Högskolan i Halmstad. BHG.
    Design and Development a Multi-Portable Lift Platform Trolleys for the Large Warehouses and Markets2018Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
  • 50.
    Nilsson, Bertil
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Maskinteknisk produktframtagning (MTEK), Funktionella ytor.
    Hansbo, Peter
    Department of Applied Mechanics, Chalmers University of Technology, Gothenburg, Sweden.
    A goal oriented adaptive finite element method for hydrodynamic lubricationManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    We present a goal-oriented adaptive finite element method for a cavitation model based on Reynolds' equation. A posteriori error estimates and adaptive algorithms are derived, and numerical examples illustrating the theory are supplied.

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