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Nyckeln bakom framgång inom all form av ingenjörskap såväl som produktutveckling inom alla marknader är kapaciteten att tillverka nya och förbättrade produkter. Kraven och behovet av bättre och bättre produkter har medfört en konstant utveckling inom tillverkningssystem från de traditionella metoderna som smidning, borrning och gjutning, till de moderna additiva systemen.  Detta arbete, som skapades i samarbete med KTH:s institution för maskinkonstruktion, undersöker och utreder 5 av de 7 stora familjerna av additivt tillverkande system med syftet att försöka definiera den framtida potentialen för additiv tillverkning. I samband med detta presenteras även förslag på produkter eller yrken som möjliggörs av systemet som utreds för att på en ytlig nivå tydliggöra egenskaperna hos varje system.  Arbetet redovisar även produktframtagningen av en högt individanpassad produkt, skyddande skal för små modeller, motivering till val av möjligt system för produkten och resultatet av en iterativ process.  Utredningen, produktframtagningen samt expertåsikter ger en diskussion som betraktar både additiv tillverknings framtida potential såväl som en diskussion om hur denna potential påverkas av Covid-19 pandemin 2020.  Som slutsats är möjligheterna för additiv tillverkning mycket lovande med flera olika riktningar utvecklingen kan gå. / The key to progress within every form of engineering in addition to product development whihin all markets is the capacity to manufacture new and improved products. The demands and need flr better and better products has brought forth a constant evolution within manufacturing systems from the traditional methods as forging, drilling and casting, to the modern additive systems.  This work, created in association with KTHs Department of machine design, examines and investigates 5 out of the 7 major families of additive manufacturing with the purpose of trying to define the future potential of additive manufacturing. In addition, for each system, a possible product or profession is suggested, made possible by the system in question. This is done to clarify the characteristics of that system.  This work also demonstrates the product development of a highly customized product, protective shells for small models, motivation behind the additive system of choice and the result of the iterative design process.  The investigation, the product development as well as expert opinion resulted in a discussion that both considers additive manufacturing future potential as well as how this potential is affected by the Covid-19 pandemic of 2020.  As a conclusion is the future for additive manufacturing very promising with several different directions in which development can go.

Passive and compact heat dissipation systems are and will remain vital for the successful operation of modern electronic systems. Oscillating heat pipes (OHPs) have been a part of this research area since their inception due to their ability to passively manage high heat fluxes. In the current investigation, different designs of tubular, flat plate, and multiple layer oscillating heat pipes are studied by using different operating parameters to investigate the operating limitations of each design. Furthermore, selective laser melting was demonstrated as a new OHP manufacturing technique and was used to create a compact multiple layer flat plate OHP. A 7-turn tubular oscillating heat pipe (T-OHP) was created and tested experimentally with three working fluids (water, acetone, and n-pentane) and different orientations (horizontal, vertical top heating, and vertical bottom heating). For vertical, T-OHP was tested with the condenser at 0°, 45° and 90° bend angle from the y-axis (achieved by bending the OHP in the adiabatic) in both bottom and top heating modes. The results show that T-OHP thermal performance depends on the bend angle, working fluid, and orientation. Another design of L-shape closed loop square microchannel (750 x 750 microns) copper heat pipe was fabricated from copper to create a thermal connector with thermal resistance < 0.09 ˚C/W for electronic boards. The TC-OHP was able to manage heat rates up to 250 W. A laser powder bed fusion (L-PBF) additive manufacturing (AM) method was employed for fabricating a multi-layered, Ti-6Al-4V oscillating heat pipe (ML-OHP). The 50.8 x 38.1 x 15.75 mm3 ML-OHP consisted of four inter-connected layers of circular mini-channels, as well an integrated, hermetic-grade fill port. A series of experiments were conducted to characterize the ML-OHP thermal performance by varying power input (up to 50 W), working fluid (water, acetone, NovecTM 7200, and n-pentane), and operating orientation (vertical bottom-heating, horizontal, and vertical top-heating). The ML-OHP was found to operate effectively for all working fluids and orientations investigated, demonstrating that the OHP can function in a multi-layered form, and further indicating that one can ‘stack’ multiple, interconnected OHPs within flat media for increased thermal management.

The goal of this study is to investigate the microstructure and microstructure-based fatigue (MSF) model of additively-manufactured (AM) metallic materials. Several challenges associated with different metals produced through additive manufacturing (Laser Enhanced Net Shaping – LENS®) have been addressed experimentally and numerically. Significant research efforts are focused on optimizing the process parameters for AM manufacturing; however, achieving a homogenous, defectree AM product immediately after its fabrication without postabrication processing has not been fully established yet. Thus, in order to adopt AM materials for applications, a thorough understanding of the impact of AM process parameters on the mechanical behavior of AM parts based on their resultant microstructure is required. Therefore, experiments in this study elucidate the effects of process parameters – i.e. laser power, traverse speed and powder feed rate – on the microstructural characteristics and mechanical properties of AM specimens. A majority of fatigue data in the literature are on rotation/bending test of wrought specimens; however, few studies examined the fatigue behavior of AM specimens. So, investigating the fatigue resistance and failure mechanism of AM specimens fabricated via LENS® is crucial. Finally, a microstructure-based MultiStage Fatigue (MSF) model for AM specimens is proposed. For calibration of the model, fatigue experiments were exploited to determine structure-property relations for an AM alloy. Additional modifications to the microstructurally-based MSF Model were implemented based on microstructural analysis of the fracture surfaces – e.g. grain misorientation and grain orientation angles were added to the MSF code.

Additive manufacturing is becoming a leading technology in the production of consumer parts. In order to compete with traditional methods which have had years to improve, additive systems must achieve a level of performance efficiency greater than it maintains today. While great effort is being expended to improve the printing time and add more systems level thinking to the problem, it is currently lacking a robust improvement methodology. To achieve the desired improvement, a technique from traditional manufacturing based on overall equipment effectiveness (OEE) is proposed. Overall additive manufacturing effectiveness (OAME) provides a methodology for enhancing this important emerging technology.