Thousands of the Swedish population suffer from eczema which is an inflam- mation of the skin. Hand eczema is a big problem while washing the dishesbecause the skin is exposed to huge amounts of water and washing-up liquid.Solely using dishwashing gloves doesn’t always solve the problem, the humidenvironment that arises in the glove can irritate the skin and exacerbatethe eczema. This report will consider the material choices of a dishwashingglove consisting of multi-layers. Horizontal and vertical wicking and absorp-tion tests were done to investigate the moisture management properties ofdifferent materials. The sanitary pads and a cotton fabric named Allväv Eko,showed the highest absorbency. A polyester fabric named Per.-Elastic andthe sanitary pad had the highest wicking properties. The suggested outerlayer was neoprene because it is waterproof. Since the results indicated ahigh absorbency in cotton, this was the proposed absorption layer. Lastly,polyester was proposed as an inner layer because it has shown to have a highmoisture permeability. Suggestions to future studies is to analyse the multi-layers in combination with each other as properties of different materials canbehave different together.

Detta examensarbete har utförts på initiativ av Scania CV AB. Scania är en världsledande tillverkare av tunga lastbilar, bussar och industri- och marinmotorer. Konstruktionsgruppen inom Scania som detta examensarbete utfördes vid är benämnd NMKA och är en del av avdelningen NM – Engine development som bedriver forskning & utveckling av Scania motorer. Denna avhandling inom produktutveckling tjänar syftet som slutgiltigt examinationsmoment för civilingenjörsprogrammet Innovation och produktdesign på Mälardalens högskola. Arbetet har utgått ifrån en metod för produktutveckling som lärs ut i samband med utbildningen. Uppdraget har baserats på frågeställningen att utveckla ett robust klamningskoncept för kablage på motor, som uppfyller de ergonomiska och konstruktionsmässiga krav som Scania ställer på sina artiklar. Klamningskonceptet ska därmed möjliggöra säker infästning av lättare kabel, rör och slang i flera olika dimensioner. Samt även kunna upprätthålla denna funktion under de stränga förhållanden som råder i miljön kring motor. Vilket ställer höga krav på brukstemperatur, kemikaliebeständighet, egenfrekvens och livslängd. Det befintliga infästningselement som används idag i aktuella applikationsområden uppfyller inte Scanias ergonomiska krav och måste därför fasas ut och ersättas. En begränsning som medföljer är att det nya klamningskonceptets artikelpris måste ligga inom samma prisspektrum som sin föregångare. En stor del av Scanias verksamhet är belägen i Södertälje, däribland produktionslinan för montering av raka motorer till lastbil, buss och marina applikationer. Monteringen av motorkomponenter sker i hög grad manuellt, vilket medför repetitiva och ibland ergonomiskt påfrestande moment för montörerna. Scania värnar om sina anställda och prioriterar deras hälsa högt så att dem kan känna sig trygga i sin arbetsmiljö och fullfölja ett långt arbetsliv. Att ta fram och utveckla nya produktlösningar som minimerar eller motverkar riskerna för skador är därför en naturlig del av förbättringsarbetet. Samt en bidragande faktor till initiativet bakom formuleringen till detta examensarbete. Detta examensarbete har resulterat i ett förslag på ett klamningskoncept som har lägre artikelkostnad, är mer ergonomisk att montera och har kortare monteringstid. Klamningskonceptet är avsett enbart för applikationsområden med lättare rör och kablage, med infästning för M6-skruvförband. På det testade applikationsområdet avluftningsnätet innebär gruppens klamningskoncept en årlig kostnadsreducering på 50 % relativt det nuvarande infästningselementet.

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This thesis was written on behalf of SOMAS instruments AB. SOMAS develops, manufactures and markets valves. The mission was to reduce the wear between the disc edge and the seat in a butterfly valve that are used at high temperatures. This study investigated the possibility of using a surface treatment or coating that can reduce wear or if a new base material is better to use than the current steel 316 material. Possible materials, surface treatments and coatings were investigated and compared in a material study. In discussion with the company, four test pairs were chosen; • Steel 316 - Steel 316 • Steel 316 - Nitronic 60 • Nitronic 60 - Nitronic 60 • Steel 316 - Steel 316 with a surface coating of Tribaloy T-400 The wear behavior of the selected materials was investigated using a test rig at Karlstad University based on the method of block-on-ring. The machine spins a cylinder that corresponds to the seat against a block which in this case corresponds to the disc edge. The tests were carried out at room temperature, 250 ˚C and 500 ˚C. The cylinder was spinning at a speed of 100 rpm while the block pressed against with a load of 50 N. A profilometer, micro-hardness tester and scanning electron microscope (SEM) were used to investigate the wear. A comparison was made based on the volume of material removed from the blocks, the maximum wear depth of the blocks and the maximum wear depth of the cylinder. Wear mechanisms, chemical composition and hardness profiles were used to explain differences in results. The results were compared with the steel 316 to steel 316 solution. The Tribaloy T-400 showed good properties to reduce the wear at room temperature. Block made of Tribaloy T-400 showed no wear, instead steel from the cylinder had been adhered to the blocks. At higher temperatures, the amount of adhered material on the tribaloy T-400 increased, resulting in more wear at the surface of the cylinder than at room temperature. The wear on the cylinder was comparable to the wear of a steel cylinder that slid against a steel block. Nitronic 60 against nitronic 60 exhibited a significant reduction in wear compared with steel to steel at room temperature. At higher temperatures, nitronic 60 against nitronic 60 was the test pair that exhibited least wear. Nitronic 60 is recommended for further examination as a material in both the disc edge and the seat in a butterfly valve to be used at both room temperature and elevated temperatures. / Detta examensarbete skrevs på uppdrag från SOMAS instruments AB. SOMAS utvecklar, tillverkar och marknadsför ventiler. Uppdraget gick ut på att minska nötningen mellan spjällkanten och sätet i en vridspjällsventil som ska användas i höga temperaturer. Denna studie undersökte möjligheten det att använda en ytbehandling eller ytbeläggning som kan minska nötningen eller om ett nytt basmaterial är bättre att använda än det nuvarande materialet stål 316. Möjliga material, ytbehandlingar och ytbeläggningar undersöktes och jämfördes i en materialstudie. I diskussion tillsammans med företaget så valdes fyra stycken testpar; • stål 316 - stål 316 • stål 316 - nitronic 60 • nitronic 60 - nitronic 60 • stål 316 - stål 316 med en ytbeläggning av tribaloy T-400 Nötningsbeteendet hos de valda materialen undersöktes med hjälp av en testrigg på Karlstad universitet som bygger på metoden ”block-on-ring”. Maskinen snurrar en cylinder som motsvarar sätet mot ett block som i detta fall motsvarar spjällkanten. Testerna utfördes i rumstemperatur, 250 ˚C och 500 ˚C. Cylindern snurrade med en hastighet av 100 rpm medan blocket tryckte mot med en last på 50 N. En profilometer, mikrohårdhetstestare och svepelektronmikroskåp användes för att undersöka nötningen. En jämförelse gjordes baserad på volymen av det bortnötta materialet från blocken, maximala nötningsdjupet på blocken och maximala nötningsdjupet på cylindern. Slitagemekanismer, kemisk sammansättning och hårdhetsprofiler användes för att kunna förklara skillnader i resultaten. Resultaten jämfördes mot stål 316 mot stål 316. Tribaloy T-400 visade upp bra egenskaper för att kunna minska nötningen i rumstemperatur. Block gjorda av Tribaloy T-400 uppvisade ingen nötning, istället hade material från stål cylindern adderats på blocken. Vid högre temperaturer så ökade mängden adderat material på tribaloy T-400 vilket resulterade i att ytan på cylindern uppvisade mer nötning än i rumstemperatur. Nötningen på cylindern kunde jämföras med nötningen hos en stålcylinder som glidit mot ett stål block. Nitronic mot nitronic uppvisade vid rumstemperatur en stor minskning av nötning jämfört med stål mot stål. Vid högre temperatur var nitronic 60 mot nitronic 60 det test par som uppvisade minst nötning. Nitronic 60 rekommenderas för vidare undersökning som material i både spjällkanten och sätet i en vridspjällsventil som ska användas i både rumstemperatur och i höga temperaturer.

A typical hard coating on metal cutting inserts used in for example turning, milling or drilling operations is TiAlN. At elevated temperatures, TiAlN exhibits a well characterized spinodal decomposition into coherent cubic TiN and AlN rich domains, which is followed by a transformation from cubic to hexagonal AlN. Using in-situ synchrotron x-ray radiation, the kinetics of the second transformation was investigated in this thesis and the strong temperature dependence on the transformation rate indicated a diffusion based nucleation and growth mechanism. The results gave additional information regarding activation energy of the transformation and the critical wavelength of the cubic domains at the onset of hexagonal AlN. After nucleation and growth, the hexagonal domains showed a striking resemblance with the preexisting cubic AlN microstructure. During metal cutting, the tool protecting coating is subjected to temperatures of ~900 ºC and pressure levels in the GPa range. The results in this thesis have shown a twofold effect of the pressure on the decomposition steps. Firstly, the spinodal decomposition was promoted by the applied pressure during metal cutting which was shown by comparisons with annealed samples at similar temperatures. Secondly, the detrimental transformation from cubic to hexagonal AlN was shown to be suppressed at elevated hydrostatic pressures. A theoretical pressure/temperature phase diagram, validated with experimental results, also showed suppression of hexagonal AlN by an increased temperature at elevated pressures. The spinodal decomposition during annealing and metal cutting was in this work also shown to be strongly affected by the elastic anisotropy of TiAlN, where the phase separation was aligned along the elastically softer <100> directions in the crystal. The presence of the anisotropic microstructure enhanced the mechanical properties compared to the isotropic case, mainly due to a shorter distance between the c-AlN and c-TiN domains in the anisotropic case. Further improvement of the metal cutting behavior was realized by depositing individual layers with an alternating bias. The individual bias layers exhibited microstructural differences with different residual stress states. The results of the metal cutting tests showed an enhanced wear resistance in terms of both crater and flank wear compared to coatings deposited with a fixed bias.

The purpose of this thesis is to provide an overview of the methods used in the appended papers, in order to consider heterogeneous material properties in finite element simulations by using process simulations as input. The work deals with both injection moulded and cast components, and focuses on process-induced local material variations and their effect on component performance. The influence of heterogeneous properties originating from the casting process as well as some other common simplifications, which are made in finite element analyses, are evaluated for a cast iron component. It is found that commonly neglected properties such as compressive strength, residual stresses, temperature dependency and heterogeneous properties have a non-trivial and potentially large influence on the simulation results. Lastly, a computational method for fibre reinforced plastics is presented. The methodology enables designers to consider the non-linear anisotropic properties of fibre-reinforced polymers, due to the flow-induced fibre orientation predicted by injection moulding simulations. The method allows material data assignment in each integration-point of the structural mesh. The method is demonstrated to capture the behaviour of the full range of fibre orientations simultaneously with good accuracy. / Syftet med denna avhandling är att översiktligt beskriva de metoder som används i de bifogade artiklarna. Dessa metoder möjliggör beaktandet av heterogena materialegenskaper vid hållfasthetsberäkningar med hjälp av finita element metoden (FEM), genom att först simulera tillverkningsprocessen. Arbetet behandlar både formsprutade och gjutna komponenter, och fokuserar på process-inducerade lokala materialvariationer, samt hur dessa påverkar komponenters prestanda. En gjutjärnskomponent har studerats med syftet att undersöka inverkan av heterogena materialegenskaper från gjutprocessen, samt några andra vanligt förekommande förenklingar som görs i industriella hållfasthetsanalyser. Genom att försumma materialets kompressionsbeteende, eventuella restspänningar ifrån gjutprocessen, temperaturberoende, samt den heterogena fördelningen av materialegenskaper ifrån tillverkningsprocessen introduceras icke-triviala och potentiellt stora fel i simuleringsresultaten. Slutligen presenteras en beräkningsmetod för fiberförstärkta formsprutade plaster. Initiala simuleringar av formsprutningsprocessen används för att prediktera den lokala fiberorienteringen, vilken används för att möjliggöra hållfasthetsberäkningar som tar hänsyn till det olinjära och anisotropa materialbeteendet hos formsprutade fiberförstärkta komponenter. Metoden möjliggör att materialdata kan appliceras i varje integrationspunkt i beräkningsnätet, och har utvärderats genom att demonstrera ett korrekt materialbeteende för flera fiberorienteringar samtidigt, med god noggrannhet.

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In order to determine storage life for aluminum alloys it is essential to have a good knowledge on the accelerated aging behavior and the mechanical properties that are affected. The selected aluminum alloys are AA2017, AA6082, AA7075 and the study has been focused on their impact toughness and hardness relation to aging beyond peak conditions. To be able to plot the mechanical properties versus aging time and temperature, Differential Scanning Calorimetric runs have been the key to obtain supporting activation energies for a specific transformation. The activation energies have been calculated according to the Kissinger method, plotted in Matlab. Arrhenius correlation has also been applied to predict the natural aging time for long time storage in 30 degrees Celsius. It could be concluded that the results from the mechanical test series show that the constructed Arrhenius 3D method did not meet the expectations to extrapolate constant activation energies down to storage life condition. Scanning electron microscopy together with light optical microscopy analyses show how important it is to apply notches in proper test specimen directions and how precipitates are grown, as it will affect impact toughness and hardness. An ending discussion is held to explain how mechanical testing progressed and how other external issues affected the master thesis operations.

The use of ceramic material as refractories in the manufacturing industry is a common practice worldwide. During usage, for example in the production of steel, these materials do experience severe working conditions including high temperatures, low pressures and corrosive environments. This results in lowered service lives and high consumptions of these materials. This, in turn, affects the productivity of the whole steel plant and thereby the cost. In order to investigate how the service life can be improved, studies have been carried out for refractories used in the inner lining of the steel ladles. More specifically, from the slag zone, where the corrosion is most severe. By combining thermodynamic simulations, plant trails and post-mortem studies of the refractories after service, vital information about the behaviour of the slagline refractories during steel refining and the causes of the accelerated wear in this ladle area has been achieved. The results from these studies show that the wear of the slagline refractories of the ladle is initiated at the preheating station, through reduction-oxidation reactions. The degree of the decarburization process is mostly dependent on the preheating fuel or the environment. For refractories without antioxidants, refractory decarburization is slower when coal gas is used in ladle preheating than when a mixture of oil and air is used. In addition, ladle preheating of the refractories without antioxidants leads to direct wear of the slagline refractories. This is due to the total loss of the matrix strength, which results in a sand-like product. Thermal chemical changes that take place in the slagline refractories are due to the MgO-C reaction as well as the formation of liquid phases from impurity oxides. In addition, the decrease in the system pressure during steel refining makes the MgO-C reaction take place at the steel refining temperatures. This reduces the refractory’s resistance to corrosion. This is a serious problem for both the magnesia-carbon and dolomite-carbon refractories. The studies of the reactions between the slagline refractories and the different slag compositions showed that slags rich in iron oxide lead mostly to the oxidation of carbon/graphite in the carbon-containing refractories. This leads to an increased porosity and wettability and therefore an enhanced penetration of slag into the refractory structure. If the slag contains high contents of alumina and or silica (such as the steel refining slag), reactions between the slag components and the dolomite-carbon refractory are promoted. This leads to the formation of low-temperature melting phases such as calcium-aluminates and silicates. The state of these reaction products during steel refining leads to an accelerated wear of the dolomite-carbon refractory. The main products of the reactions between the magnesia-carbon refractory and the steel refining slag are MgAl2O4 spinels, and calcium-aluminates, and silicates. Due to the good refractory properties of MgAl2O4 spinels, the slag corrosion resistance of the magnesiacarbon refractory is promoted. / QC 20101013