Polymer nanocomposites are a going part of Materials Science and Engineering. These new composite materials exhibit dimensional and thermal stability of inorganic materials and toughness and dielectric properties of polymers. Development of nanocomposites become an important approach to create high-performance composite materials. In this study silica, fly ash, silica nanotubes and carbon black particles have been added to modify polyurethane foam and thermoplastic polyurethanes. It has been found that the addition of silica can diminish the size of foam bubbles, resulting in an increased stiffness of the material, increase of the compressive strength, and greater resistance to deformation. However, the uniformity of bubbles is reduced, resulting in increased friction of the material. Fly ash added to the foam can make bubbles smaller and improve uniformity of cells. Therefore, the material stiffness and compressive strength, resistance to deformation, and has little impact on the dynamic friction of the material. Adding nanotubes make bubble size unequal, and the arrangement of the bubble uneven, resulting in decreased strength of the material, while the friction increases. After the addition of carbon black to the polyurethane foam, due to the special surface structure of the carbon black, the foam generates more bubbles during the foaming process changing the foam structure. Therefore, the material becomes soft, we obtain a flexible polyurethane foam. The results of mechanical properties determination of the thermoplastic polyurethane that adding particles may increase the stiffness and wear resistance of the thermoplastic polyurethane, while the tensile properties of the material are reduced. This phenomenon may be due to agglomeration of particles during the mixing process. Possibly the particles cannot be uniformly dispersed in the thermoplastic polyurethane.

This thesis was made in collaboration with Aktiv Ortopedteknik’s clinic in Västerås, they are knowledgeable about orthopedic products individually customized for their customers. They have examined the possibility of 3D printed orthotics with need for hard support, but so far, the technology for softer orthotics like shoe insoles has not been explored. The thesis explores the possibility of how the 3D printing technology can improve the cost and active involvement for the technicians. Initially the tools and possibilities were limited by accessibility and budget, and the project leads to the examination of specifically material extrusion printing with the flexible filament TPU. To accomplish this, Aktiv Ortopedtekniks methods are tested on how they can be digitalized with their existing tools, this is done to maintain the processing needs the technicians have. Later the material is tested on its grinding possibility, the fatigue effects, and resistance to compression in two variants of infill structures and material, all done in Mälardalens University’s workshop. The results of material testing show good possibilities to grinding, which were verified in Aktiv Ortopedtekniks workshop. The fatigue test was only done to 10% of the planned number of cycles and could not be used for any conclusive result about if the 3D printed insole has a similar usage time to the orthopedic insoles they currently offer. The pressure tests point to that a similar compression to multiple of Aktiv Ortopedtekniks material is possible to achieve through variation in the infill structure, although the compression acts slightly different graphically. PrusaSlicer estimates a printing time and material cost, where the time it would take to print gives a max capacity of 40 pairs of insoles per week, per machine. The material cost varies to be cheaper for the small sizes and more expensive for the bigger sizes with a middle of roughly the same price for size 39. The active time of involvement after the print may include grinding in two areas of the insole. For future studies, it is recommended to further explore those experiments that are simplified or incomplete, and to expand research into other fields. Experiments should also be performed using more optimized, industrial 3D printers for a more consistent result. / Den här studien utfördes i samarbete med Aktiv Ortopedtekniks klinik i Västerås, som besitter kunskap i individanpassning och behov kring utformning av ortoser. De har börjat undersöka 3D-utskrifter i styvt material för ortoser där ett hårdare stöd behövs, men hittills har inte teknologin inom företaget undersökts för mjukare ortoser, som skoinlägg. Arbetet ämnar undersöka några möjligheter som 3D-utskriftsteknologi kan bidra till med hänsyn till pris och bearbetning. Inledningsvis avgränsas verktygen och möjligheterna efter tillgång och budget, och arbetet leder till att undersöka specifikt materialextruderingsutskrifter med flexibelt TPU-material. För detta testas först hur Aktiv Ortopedtekniks metoder kan digitaliseras med de verktyg de har tillgängliga, och hur detta kan göras för att bibehålla de bearbetningsbehov teknikerna har. Sedan undersöks materialet genom test av möjlighet till slipning, effekter av utmattning och motståndskraft vid hoptryckning av variationer av två olika utfyllnadsmönster och material, allt i Mälardalens Universitets verkstadsmiljö. Resultatet av materialtesten visar goda möjligheter till slipning, och verifierades i Aktiv Ortopedtekniks verkstad. Utmattningsprovet uppnådde och klarade av endast 10% av den tänkta mängden cykler och kan ej användas för att dra en slutsats kring om det 3D-utskrivnainlägget har en liknande hållbarhetstid. Trycktesten tyder på att motståndskraft liknande den i ett flertal av Aktiv Ortopedtekniks material går att uppnå genom att variera den inre strukturen, men att motståndskraften som en funktion av hoppressning agerar annorlunda. Beredningsprogrammets uppskattning kring utskriftstid och materialkostnader ger en utskriftstid som inte håller för en kapacitet på 40 par i veckan, per maskin, och en materialkostnad som varierar mellan billigare för små skor och dyrare för större, med ett motsvarande likställt värde för storlek 39. Handpåläggningstid i efterhand innefattar eventuell slipning i två områden. För framtida studier rekommenderas att djupare undersöka de olika tester som simplifierats eller ej fullföljts i denna undersökning, och att vidga forskningen till andra studieområden. Tester bör även göras med en för syftet mer optimerad industriell 3D-skrivare för ett mer konsekvent resultat.

If Swedish companies are to compete with companies in low-cost countries they have to achieve a more efficient production. The purpose of Total Productivity Maintenance (TPM) is to increase the company's profitability by increasing the productivity. TPM is a method that involves all employees and aims to prevent failures in order to increase the availability of existing equipment. The aim of this paper is to evaluate the implementation process of TPM and give recommendations for the further implementation process. The conclusion and the analysis are based on a case study done at a production department at ABB Cewe-Controls facilities in Nyköping. The case study consists mainly of qualitative data from participation observations, surveys and interviews. Commitment of the management is a key factor in the implementation process of TPM. The management of ABB Cewe-Control need to demonstrate their commitment in order for a change to happen. The case study shows that the commitment of both employee and management must be raised if the implementation process is to be successful. To avoid unnecessary conflicts or irritation in the further implementation process it is important to clarify responsibilities and roles in the implementation of TPM. The case study has also shown that the training during the implementation process has not been sufficient. Proper training is needed to be able to conduct the implementation process of TPM in an effective manner. Proper training is also needed to raise the motivation of the staff. Business Development is ABB’s methodology for the improvement work in the company. Business Development is a well-known concept in the organisation and has a well-defined connection with the company's strategic objectives. Because of this there is no reason why the improvement work and how it has been done should change. Business Development is a good foundation for the implementation of TPM and the improvement work in the future. / För att svenska företag ska kunna konkurrera med företag som har produktion i lågkostnadsländer måste företagen bedriva en effektivare produktion. Syftet med totalt produktivt underhåll (TPU) är att öka företagets lönsamhet genom att höja produktiviteten. TPU är ett arbetssätt där alla medarbetare ska engageras för att minimera störningar och haverier så att utrustningseffektiviteten kan höjas. Syftet med rapporten är att utvärdera implementeringen av TPU på ABB Cewe-Control i Nyköping och ge rekommendationer för den fortsatta implementeringen. Som grund för analys och slutsats har en fallstudie på ett pilotavsnitt genomförts. Fallstudien byggs upp till största delen av kvalitativ data i form av deltagande observationer, enkäter och intervjuer. Ledningens engagemang är den mest centrala faktorn i implementeringen av TPU. Produktionsledningen på ABB Cewe-Control måste tydligare visa engagemanget i aktiva handlingar för att en förändring ska kunna ske. Resultatet från fallstudien visar på att både medarbetarnas och produktionsledningens engagemang måste höjas för att verksamheten ska kunna utvecklas. För att det framtida arbetet inte heller ska drabbas av onödiga konflikter eller irritation är det viktigt att tydliggöra ansvar och roller vid implementeringen av TPU. Fallstudien har också visat på att utbildningen under implementeringen inte har varit tillräcklig. Ordentlig utbildningen behövs för att TPU-arbetet ska kunna bedrivas på ett effektivt sätt och för att höja motivationen hos medarbetarna. Den förbättringsverksamhet som tidigare har bedrivits inom ramarna för verksamhetsutveckling (VU) är en mycket bra grund för förbättringsarbetet i TPU. Det finns ingen anledning till att inte fortsätta med förbättringsverksamheten enligt VU eftersom det är inarbetat i verksamheten och då VU så tydligt kopplar samman gruppernas arbete med företagets strategiska mål.

The purpose with this bachelor thesis is to identify risks and insufficiencies concerning the production at WilloMaskin AB. The project is limited to only 4 machines, where theories as “OEE” (overall equipment efficacy) should be illuminated and analyzed. The theory of “Single Minute Exchange of Die” is also presented. The method used in this project is mostly based on qualitative studies but also quantitative studies are presented. Information has been gathered from Willo Maskin ABs own calculations, the university library of Växjö and electronical sources. The studies have been made through observation and notes of the production process at the workplace. Routines have been checked and discussions with people involved in the process have been passed. The observation also included machine stand still measurement and OEE calculations. The measuring for each machine under a time period shows the lack in the production progress and the methods used. The results show that the machine adjustment is the part of the process that requires the most production time. Discussions with machine operators prove that a lot of them don’t know how to handle new machines. However, the machines work very efficient when they work. It takes short adjustments and further education of operators to increase the availability. The introduction of different production follow-up systems is necessary to be able to measure, and in a long term even reduce the reasons of standstill.

<p>If Swedish companies are to compete with companies in low-cost countries they have to achieve a more efficient production. The purpose of Total Productivity Maintenance (TPM) is to increase the company's profitability by increasing the productivity. TPM is a method that involves all employees and aims to prevent failures in order to increase the availability of existing equipment.</p><p>The aim of this paper is to evaluate the implementation process of TPM and give recommendations for the further implementation process. The conclusion and the analysis are based on a case study done at a production department at ABB Cewe-Controls facilities in Nyköping. The case study consists mainly of qualitative data from participation observations, surveys and interviews.</p><p>Commitment of the management is a key factor in the implementation process of TPM. The management of ABB Cewe-Control need to demonstrate their commitment in order for a change to happen. The case study shows that the commitment of both employee and management must be raised if the implementation process is to be successful. To avoid unnecessary conflicts or irritation in the further implementation process it is important to clarify responsibilities and roles in the implementation of TPM.</p><p>The case study has also shown that the training during the implementation process has not been sufficient. Proper training is needed to be able to conduct the implementation process of TPM in an effective manner. Proper training is also needed to raise the motivation of the staff.</p><p>Business Development is ABB’s methodology for the improvement work in the company. Business Development is a well-known concept in the organisation and has a well-defined connection with the company's strategic objectives. Because of this there is no reason why the improvement work and how it has been done should change. Business Development is a good foundation for the implementation of TPM and the improvement work in the future.</p> / <p>För att svenska företag ska kunna konkurrera med företag som har produktion i lågkostnadsländer måste företagen bedriva en effektivare produktion. Syftet med totalt produktivt underhåll (TPU) är att öka företagets lönsamhet genom att höja produktiviteten. TPU är ett arbetssätt där alla medarbetare ska engageras för att minimera störningar och haverier så att utrustningseffektiviteten kan höjas.</p><p>Syftet med rapporten är att utvärdera implementeringen av TPU på ABB Cewe-Control i Nyköping och ge rekommendationer för den fortsatta implementeringen. Som grund för analys och slutsats har en fallstudie på ett pilotavsnitt genomförts. Fallstudien byggs upp till största delen av kvalitativ data i form av deltagande observationer, enkäter och intervjuer.</p><p>Ledningens engagemang är den mest centrala faktorn i implementeringen av TPU. Produktionsledningen på ABB Cewe-Control måste tydligare visa engagemanget i aktiva handlingar för att en förändring ska kunna ske. Resultatet från fallstudien visar på att både medarbetarnas och produktionsledningens engagemang måste höjas för att verksamheten ska kunna utvecklas. För att det framtida arbetet inte heller ska drabbas av onödiga konflikter eller irritation är det viktigt att tydliggöra ansvar och roller vid implementeringen av TPU.</p><p>Fallstudien har också visat på att utbildningen under implementeringen inte har varit tillräcklig. Ordentlig utbildningen behövs för att TPU-arbetet ska kunna bedrivas på ett effektivt sätt och för att höja motivationen hos medarbetarna.</p><p>Den förbättringsverksamhet som tidigare har bedrivits inom ramarna för verksamhetsutveckling (VU) är en mycket bra grund för förbättringsarbetet i TPU. Det finns ingen anledning till att inte fortsätta med förbättringsverksamheten enligt VU eftersom det är inarbetat i verksamheten och då VU så tydligt kopplar samman gruppernas arbete med företagets strategiska mål.</p>

<p>The purpose with this bachelor thesis is to identify risks and insufficiencies concerning the production at WilloMaskin AB. The project is limited to only 4 machines, where theories as “OEE” (overall equipment efficacy) should be illuminated and analyzed. The theory of “Single Minute Exchange of Die” is also presented.</p><p>The method used in this project is mostly based on qualitative studies but also quantitative studies are presented. Information has been gathered from Willo Maskin ABs own calculations, the university library of Växjö and electronical sources. The studies have been made through observation and notes of the production process at the workplace. Routines have been checked and discussions with people involved in the process have been passed. The observation also included machine stand still measurement and OEE calculations. The measuring for each machine under a time period shows the lack in the production progress and the methods used. The results show that the machine adjustment is the part of the process that requires the most production time. Discussions with machine operators prove that a lot of them don’t know how to handle new machines. However, the machines work very efficient when they work. It takes short adjustments and further education of operators to increase the availability. The introduction of different production follow-up systems is necessary to be able to measure, and in a long term even reduce the reasons of standstill.</p>

No description available.

A stretchable silver ink was screen printed to TPU sheets, then tensile coupons of the TPU, both bare and laminated to cotton, Denim and spandex fabric, were subjected to 1000 cycles of 20% uniaxial strain. In-situ resistance measurements of printed traces were processed to generate datasets of maximum and minimum resistance per cycle. A mechanistic fit model was used to predict the resistance behavior of the ink across TPU/fabric levels. The results show that traces strained on TPU laminated to spandex (polyester) fibers had an average rate of increase in resistance significantly lower than that of traces strained on bare TPU. The variation in predicted resistance was significantly lower in the spandex group than in the TPU group. Trace width was not found to have a significant effect on the resistance behavior across TPU/fabric groups. More testing is required to understand the effect of lamination to high elasticity fabrics on resistance behavior as it relates to the viscoelastic properties of the fibers and weave structure.

A polymer laminate consisting of multiple layers of proprietary blends of Ethylene Vinyl Alcohol (EVOH) and Thermoplastic Polyurethane (TPU) and used in the construction of air bladders was evaluated for hygroscopic effects driving delamination and multiple layer fragmentation. These air bladders are observed to suffer delamination during a manufacturing process that involves immersion in an alcohol/water solution. A plausible underlying mechanism is differential swelling and absorption by the laminate constituents. Both room and elevated temperature swelling tests were carried out to find the absorption and swelling coefficients of the constituents. These coefficients served as input into a Finite Element Analysis (FEA) model used to predict laminate failure. The diffusion coefficient for EVOH could not be obtained because the material did not reach saturation within the available timeframe of the experiment. The diffusion coefficient of the TPU was found to be 4.09E-12 [m^2/s] at room temperature and 1.26E-11 [m^2/s] at 40°C. The diffusion coefficient for TPU was an order of magnitude larger at elevated temperature and the TPU reached saturation much quicker than the EVOH, suggesting that the diffusion coefficient for the TPU was significantly greater than that of the EVOH. The swelling coefficients were 1.03E-3 m^3/kg and 9.97E-4 m^3/kg for the EVOH at room temperature and 40°C respectively, and 1.16E-3 m^3/kg and 1.09E-3 m^3/kg for the TPU at room temperature and 40°C respectively. The swelling coefficient was very close across materials and within the margin of error across temperatures. These results are required for future FEA simulations to confirm that differential swelling is the driving mechanism behind debonding and laminate failure. Tensile testing was done on laminated sheets used in production to identify cracking and layer separation at strains of 20%, 40%, and 100%. Scanning Electron Microscope (SEM) imaging was used to understand damage initiation and accumulation in the layers.

Yes / Highly oriented poly(lactic acid) (PLA)/thermoplastic polyurethane (TPU) blends were fabricated through solid hot stretching technology in an effort to improve the mechanical properties and blood biocompatibility of PLA as blood-contacting medical devices. It was found that the tensile strength and modulus of the blends can be improved dramatically by stretching. With the increase of draw ratio, the cold crystallization peak became smaller, and the glass transition and the melting peak moved to high temperature, while the crystallinity increased, and the grain size of PLA decreased, indicating of the stress-induced crystallization during drawing. The oriented blends exhibited structures with longitudinal striations which indicate the presence of micro-fibers. TPU phase was finely and homogeneously dispersed in the PLA, and after drawing, TPU domains were elongated to ellipsoid. The introduction of TPU and orientation could enhance the blood compatibility of PLA by prolonging kinetic clotting time, and decreasing hemolysis ratio and platelet activation.