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- PostFramtagning av appliceringsområden & produkter för tekniken z.trusion®(2023) Aronsson, Jesper; Berger, Moritz; Cederqvist, Filip; Eriksson, Ylva; Kalentun, Ida; Lilliedahl, Alfred; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Almefelt, Lars; Dagman, AndreasZ.trusion® är en ny innovativ tillverkningsmetod framtagen av företaget Reliefed Te chnologies som bygger på den traditionella tillverkningsmetoden extrusion. Z.trusion® är ett tillägg på en befintlig extrusionslina som utvidgar möjligheterna för formgiv ning. Det som z.trusion® innebär är möjligheten att skapa avancerade strukturer och topologier i extruderade profiler i ett enda tillverkningssteg vilket medför ett flertal fördelar. En av de främsta fördelarna är att man kan undvika vidare formgivande produktionssteg efter extrusion vilket kan spara tid, energi, material och pengar. Eftersom detta är en ny tillverkningsmetod är den inte applicerad i större utsträck ning ännu. Därmed har Reliefed Technologies startat detta projekt och gett oss i uppdrag att identifiera och undersöka potentiella områden där z.trusion® kan använ das. Inom projektet finns avgränsningar i form av teknikens begränsningar, fokus på svensk marknad samt att parallellt arbete med företagets interna utvecklingprojekt undviks. Rapporten innefattar den arbetsprocess som använts för att identifiera applicerings områden och ta fram produktförslag som nyttjar tillverkningsmetoden z.trusion®. Den övergripande processen har varit iterativ där efterforskning, idégenerering och sållning har gjorts i flera omgångar för att sedan leda till vidareutveckling. Arbe tet resulterade i flera förslag på appliceringsområden där z.trusion® kan användas. Vidare resulterade arbetet i ett koncept inom byggställningsplattformar, nämligen en ersättningsplatta till ramplattformar. Z.trusion® applicerades för att skapa en greppyta på ovansidan samt fackverksstruktur på undersidan för att minska vikten utan att försämra styvheten väsentligt. Lösningsförlaget till konceptet modellerades i CAD och strukturella egenskaper ut värderades med FEM-analys. Enligt beräkningar kunde fackverksmönstret uppnå en viktminskning på 37% jämfört med en skiva med konstant tvärsnitt. Ytterligare fördelar tillkommer i form av bättre greppyta samt möjlighet att använda materi al med längre livslängd. Vi rekommenderar att företaget fortsätter utvecklingen av byggställningsplattformar genom vidare undersökning av materialval och geometri.
- PostSingle-step production of non-assembly mechanisms using additive manufacturing(2023) Ahlberg, Malkom; Andersson, Alex; Eriksson Uggla, Aron; Fridh, Henrik; Madestam, Jakob; Melander, Sandra; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Nyborg, Lars; Khademzadeh, SaeedNon-assembly additive manufacturing is a manufacturing process that eliminates the need for assembly and joining, effectively saving time, costs, and processing whilst making it possible to create complex geometries. There are possible future applications for non-assembly mechanisms in several fields of engineering, such as expandable orthopedic implants in the biomedical industry, or weight- and volume saving constructions in the aerospace industry. While previous studies cover various aspects of additive manufacturing, design cri teria and redesign ideas for non-assembly additive manufacturing are yet to be explored thoroughly. Thus, this thesis delves into the subject through extensive research and literature studies, and a toolbox that provides these guidelines was cre ated. The study is specifically targeted toward the production of micro-mechanisms using powder bed fusion - laser beam technology. To achieve this, several questions were raised: What types of micro-mechanisms are possible to produce using addi tive manufacturing and how can these be optimized for the technology? What is the most intuitive way to present the findings of the report? The toolbox resulting from this study was built as an interactive HTML file to easily present the design criteria for each of the micro-mechanisms, along with examples of alternative designs. Lastly, prototyping in polymer with fused deposition modeling was conducted for proof of concept for the developed guidelines.
- PostMaterialkrav för komponenter i förbränningsmotorer för vätgas(2023) Abda, Deler; Andersson, Joel; Andersson, Svante; Kåhre, Hugo; Jönsson, Henrik; Torslén, Melker; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Nyborg, Mats; Norell, Mats; Cao, YuBecause of the current climate crisis hydrogen gas is investigated as a fuel for internal combustion engines. Hydrogen gas has the potential to be an environmentally friendly fuel since it can be produced with renewable electricity and it does not release carbon dioxide during combustion. One problem with hydrogen is that it embrittles many metals and thus potentially limits the material selection that could be used to construct a hydrogen powered engine. The purpose of the study is to investigate how hydrogen can affect materials and components in hydrogen powered internal combustion engines. Hydrogen embrittlement can be attributed to several mechanisms, these mechanisms are more thoroughly described during this project. This generally leads to for instance reduced ductility and fatigue limit for the affected materials. Different crystal structures have different susceptibility to this effect, for instance hydrogen diffusion is higher in BCC metals and BCC metals are embrittled to a greater extent compared to FCC metals. Different types of piston engines with internal combustion was further investigated to determine what engine type is more suited to being powered by hydrogen gas. This was done in order to determine components which are more relevant to study further. Spark ignition was percieved to be advantageous since hydrogen gas requires significantly higher compression than is currently used in compression ignition egnines. The effect of hydrogen on the alloys most commonly used in conventional internal combustion engines was studied. High strength steel, in general, embrittles to a higher extent compared to, for instance, aluminium and austenitic stainless steels. However, the variation is large even between different alloys within the same alloy group. Finally, components with direct exposure to hydrogen were studied as well as their requirements and which alloys they usually consist of. Exactly how fatigue limit and service life for different components would be affected could not be determined. Investigating this would require experiments with hydrogen powered engines for long periods of time. A conclusion is that components in proximity to the combustion chamber are critical to study further, partially because of the high concentrations of hydrogen and partially because of the high mechanical and thermal stresses.
- PostMetod för livscykelanalys för produkter tillverkade av Swedish Electro Magnets, SEM(2023) Johansson, Jim; Pettersson, Emil; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Hammersberg, Peter; Hammersberg, PeterThis report is about the development and function testing of a simplified life cycle analysis (LCA) methodology and a corresponding tool for SEM (Swedish Electro Magnets), developed using commonly available software in the Microsoft office suite. This work is done using a real case of the XPI (extreme pressure injector) stator-injector as reference, reporting on the conclusions from the test analysis. Since the main goal of the study was to develop a calculation tool, this study includes much information about how the tool was developed from the steps of Lifecycle analysis (LCA). While the results from example use of the tool have not been verified against real measured data, the tool follows the standard methodology for LCA and provides results deemed as reasonable. The stator-injector is manufactured in Åmål by SEM and is an important component of the fuel injection system for Scania truck engines. The commercial automotive industry is constantly working to reduce their environmental impact and this study is intended to help SEM identify which part of the product lifecycle is the most damaging to the environment. It is also meant to provide tools for further development of SEM products from an environmental perspective. The results from this study show that almost all emissions come from the usage of the stator-injector during its service life and that improvements in this area should be prioritised for further development. Some of the most important observations include that there is room for reduction of emissions on a per piece basis in the production, but that in the development phase the most important goal should be to increase efficiency as the absolute majority of emissions are generated during use. However, there are still possibilities for improvements in the areas of packaging and transport. The accuracy of the developed tool is highly dependent on the quality of the input data and should be considered carefully before use. The tool does however produce results roughly in line with expectations and does identify a problem area which should be prioritised for further development. This study was conducted at the department of Industrial and Material Science at Chalmers University of Technology.
- PostSmart sensors for food packaging and their implementation to the Swedish market(2022) Forne Admarker, Erik; Berisha, Tringa; Hermez, David; Hultén , Egil; Zöögling, Emma; Ahmed Mohamed, Abdulsamed; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Klement, Uta; Sun, JinhuaFood packages are essential for the maintenance of the quality and safety of food. Controlling quality and safety has always been an essential part of our life. The first expiration date originates back in 1930 and by 1985 expiration dates became compulsory for consumable products in Sweden to ensure the safety and quality of products. Since 1930 technology has been evolving rapidly. Scientists have been working on the development of intelligent packaging since 1999. An intelligent package uses smart sensors or labels that monitor the freshness of food depending on internal and external factors. However, smart sensors are not yet seen on food packages on the Swedish market. The objectives of this thesis were to determine why smart sensors are not on the Swedish market, what product could benefit the most from a sensor, and what could be done to implement them. Literature studies, interviews with different actors in the product chain, surveys, and sensor testing were different methods used to gain knowledge about the sensors and what specific type is most suitable for customer requirements. The customer survey, and interviews with both retailer and sensor developer showed that meat products are in most need of sensors. The result of the literature study and interview with sensor developer showed that some smart sensors are cheap but determining the specific limit for when a product is considered spoiled is a subjective decision with no specific standard that varies from individual to individual. In addition, the result from testing the oxygen indicator showed that reversibility is somewhat possible, however, the sensitivity is insufficient for monitoring low levels of oxygen in food packaging. The results from pH-testing showed that pH is an inefficient method for monitoring the freshness of meat because the results were contradictory to the theoretical values. Additional reasons are the high risks accompanied by having the pH sensor inside a packaging. There are many innovative sensors to monitor the quality of meat, but different products require different sensors dependent on their properties.