The Powder Bed Fusion using Electron Beam (PBF-EB) process is a highly complex additive manufacturing process. There are a very limited number of materials that have been used successfully, which limits the applications of the process, despite its well-documented advantages over conventional manufacturing. However, the development of new materials is hindered due to a lack of understanding of the fundamental phenomena in the process. The goal of this work has been to develop a model that is able to predict the process parameters that will lead to the manufacture of a fully dense component.   The model is based on 1285 empirical datasets of process parameters and the physical properties of the printed materials. Nine different materials were included in the data. By inputting a pre-defined set of process parameters and materials properties the model will output the beam power at which it is predicted a dense component may be manufactured. This novel approach will shorten the development of new process parameters by providing a first approximation of suitable parameters to iterate from. A tool steel powder supplied by Uddeholms AB was printed, using parameters proposed by the model. Two sets of pre-defined process parameters were used with several beam velocities and resulted in a number of correct predictions.   This model is a first step in predicting process parameters and presents a simple, transparent and new method of obtaining the process window for novel materials in Powder Bed Fusion using Electron Beam. / Powder Bed Fusion med Electron Beam (PBF-EB) är en mycket komplex additiv tillverkningsprocess. Det finns ett fåtal antal material som går att använda i processen. Detta är ett förhinder för applikationer trots processens väldokumenterade fördelar över konventionell framställning. Framtagning av nya material är dock hejdad på grund av okunskap kring de grundläggande fenomenen inom processen. Målet med detta arbete har varit att utveckla en modell som kan förutse processparametrar vilka ger helt kompakta komponenter.   Modellen är baserad på totalt 1285 data uppsättningar av processparametrar och de fysiska egenskaperna av de printade materialen. Data på nio olika material har samlats in. Genom att mata in ett par förbestämda processparametrar och materialets specifika materialegenskaper så beräknar modellen kraften på strålen vid vilken det förutspås att goda resultat framställs. Denna nya metod kortar ned tiden inom traditionell processparameterutveckling genom att bistå med en första iteration att arbeta utifrån. Ett verktygsstålspulver tillverkat av Uddeholms AB vart printat med hjälp av modellen. Två uppsättningar av förbestämda processparametrar användes vid flera olika stråles hastigheter och resulterade i åtskilliga lyckade förutsägelser.   Denna modell är ett första steg i att förutspå processparametrar och presenterar en simpel, transparant och ny metod till att finna process fönstret för nya material i Powder Bed Fusion med Electron Beam processen.

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Ein metastabiler austenitischer Stahl der Zusammensetzung 16Cr-7Mn-6Ni wurde einerseits über die Methode der Rückumwandlung in Werkstoffzustände verschiedener Korngrößen überführt und andererseits additiv über das Electron Beam Melting (EBM)-Verfahren gefertigt. Das statische und das zyklische Verformungsverhalten werden stark von der Korngröße beeinflusst. Insbesondere der ultrafeinkörnige Zustand verzeichnete einen erheblichen Anstieg der Festigkeit bei gleichzeitig hoher Duktilität. Die Lebensdauer übertraf bei niedrigen Dehnungsamplituden die Lebensdauer der Vergleichszustände und lag - für ultrafeinkörnige Gefüge außergewöhnlich - selbst bei hohen zyklischen Beanspruchungen auf einem vergleichbaren Niveau. Im Gegensatz zur Korngröße hatten die prozessinhärenten Defekte der mittels EBM hergestellten Varianten kaum einen Effekt auf das Verformungsverhalten des Stahls. Auch die Absenkung der Lebensdauer fiel vergleichsweise gering aus. Diese hervorragende Schadenstoleranz wird der hohen Duktilität in Kombination mit der enormen Verfestigungskapazität zugeschrieben.

Vi har gjort vårt kandidatarbete på en webbyrå i Stockholm som heter Boman Communication. Där har vi gjort en databasdriven webbplats i flash och asp. Webbplatsen är ett komplement till en kurs som heter EBM. Kursen EBM hålls av myndigheten SBU som i sin tur är en kund till Boman. Målgruppen för EBM och därmed också webbplatsens målgrupp är bland annat professorer och läkare inom medicin och vård. På kursen tar man upp riktlinjer för hur man botar olika sjukdomar eller skador. Webbplatsen innehåller information om och till kursen. Den är uppdelad i tre delar: Allmän, Före kursen och Efter kursen. Den allmänna delen är till för att väcka ett intresse för kursen hos besökaren. Denna del kommer alla åt. De två övriga delarna kräver inloggning och är bara till för dem som anmält sig på kursen. Inloggningen är datumstyrd vilket innebär att när kursen inte har varit ännu kommer man till delen före kursen och när kursen har varit kommer man till delen efter kursen. Före kursen hittar man information på webbplatsen som man bör ta del av för att förereda sig till kursen, man kan även finna information om föreläsarna och övriga kursdeltagare. Efter kursen är webbplatsen uppdaterad med en sida för dokumentation som föreläsarna har rekommenderat, här finns även en utvärdering som kursdeltagarna uppmanas att fylla i. Vi har framförallt använt oss av programmen Macromedia Flash MX 2004 och Macromedia Dreamweaver MX 2004 men även program som Adobe Photoshop CS, Adobe Illustrator CS. / Detta är en reflektionsdel till en digital medieproduktion.

The growing negative impacts of non-biodegradable plastics derived from non-renewable materials have created increasing interest throughout the world for new materials that are both biodegradable and renewable, that can be combined with or replace traditional plastics. Plant-based thermoplastic starch (TPS), a promising alternative material to traditional petroleum based resin, is both biodegradable and renewable and has great potential for use in plastic manufacturing processes. Two major obstacles that prevent more widespread use of TPS include; TPS base material, which is typically manufactured in a flake or powder, is incompatible with standard plastics production equipment that require pelletized resin, the second reason is that TPS is difficult to mix with standard plastic materials such as High Density Polyethylene (HDPE). BiologiQ of Blackfoot Idaho through a unique manufacturing process has created a new type of TPS called EcoStarch™ Resin (ESR) that overcomes these two obstacles the material can be both pelletized and combined with various standard base plastics such as HDPE. This study evaluated and characterized the processability materials properties of ESR and HDPE blends in the Extrusion Blow Molding (EBM) by measuring wall thickness, tensile strength, tensile elongation, modulus of elongation and formability compared to 100% HDPE bottles. As the ESR content increased the uniformity of the wall thickness increased. The tensile strength increased from ESR content of 30% to 50% while the elongation decreased. Bottles were successfully extrusion blow molded with ESR content of 50%.

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The titanium alloy, Ti-6Al-4V, is vastly studied and used in many applications because it has a transformation microstructure, which can be tailored for apt properties that are consistent up to 500°C. Compared to conventional steels, this alloy favours certain applications due to its high specific strength, hardenability, corrosion resistance, biocompatibility and weldability. Its weldability makes the alloy a good candidate for additive manufacturing (AM). Ti-6Al-4V parts are widely built by the AM process of electron beam melting (EBM). However, heat transfer remains crucial in EBM process. The high intensity localized, moving, electron beam heat source and the rapid self-cooling are critical, especially in thin parts/ sections. When thin sections are built by the EBM process, there will be microstructural variation in their build direction, which can lead to the variation of their mechanical properties. It is necessary to understand the microstructure and mechanical properties of thin sections when they are used as functional parts in various applications in aerospace, automotive, medical, etc. industries. The microstructure, tribological behaviour and mechanical properties of Ti-6Al-4V, as-built EBM thin plates were studied by means of various hardness, scratch and tensile testing. The hardness and scratch tests were performed on the thin plates to correlate the microstructural variation. In-situ micro tensile test was performed inside the scanning electron microscope (SEM), to see the sample’s deformation behaviour. Microstructural characterization revealed equiaxed grains in the transverse section and the longitudinal surface exhibited columnar grains elongated along the build direction. The size of the equiaxed grains are found to vary across the thickness of the plate. The indentation and scratch hardness also vary in correlation with the varying grain size across the plate’s thickness. The micro tensile results reveal that the tensile properties of the thin plate are comparable to that of its bulk Ti-6Al-4V counterpart.

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汽車產業早期在台灣一直都屬於重點產業，早從1950年代以前，台灣政府便開始發展汽車產業(陳釧瑤，1997)，然而若按照原定計畫，台灣汽車產業早該在1985年以後就邁入國際化以及自有品牌，不過現今大多數的台灣汽車廠商仍處於通路代理商和零組件代工製造階段，為了避免淘汰，本研究認為台灣汽車廠商應著手發展自有品牌，不過因為台灣廠商大多欠缺品牌知名度，謂此本研究認為台灣廠商可採行品牌聯盟策略。然而考量到市場未來趨勢與消費者需求的多元化，本次研究將以強調運動、休閒的SUV休旅車作為本次研究主要探討的車種，並希望能藉由品牌聯盟讓台灣汽車廠商得以自創品牌。 本次研究貢獻在學術方面有三，其一是產品屬性與產品屬性水準之詮釋、二是研究品牌聯盟議題時，需建立在品牌是否能替代某產品屬性的議題上，三是消費者在從事消費行為時確實會產生退縮或是漸進策略。在管理實務上，本研究所給予的建議有七，其一是品牌知名度高低將會影響消費者做出正確決定，其二是當消費者無法有效處理資訊時，車商品牌的重要性將會提升，其三是低辨識度品牌有動機發展成份品牌，其四是台灣汽車廠商自創品牌確實有其利基市場存在，其五是品牌自創過程中，必須不斷地做自我評估，其六是傳遞正確且為消費者所能承受並理解的正確資訊是價值創造的重要一環，其七是品牌建立本身即是策略規劃。 / Motor industry is one of the most important industry that Taiwan government energetically have developed and invested lots of resources since 1950(陳釧瑤，1997). Indeed, Taiwanese motor firms should have had their own brand and made it internationalized in 1985. However, most of Taiwanese motor firms are still on the stage of OEM or ODM. We regard this condition as a threat that will obstruct the profit growth and weaken the competitiveness of them. Therefore, we consider branding is one of the effective alternatives to strengthen the competitiveness of Taiwanese motor industry. Because of the low brand awareness of Taiwanese motor firms, brand alliance may be the best way that can help them to build their private label. Considering the trend of lifestyle in Taiwan, this literature will focus on “brand alliance of sport utility vehicle” and try to find some important attributes that will support them to select their partners and satisfy the consumer needs. As a result, this studying has three contributions to academic researcher. First, we redefine the meanings of product attribute and product attribute level that many academics confuse. Second, the consistency between the brand awareness of ingredient firms and product attribute should be considered when motor firms are finding the partners of alliance. Third, we verify either behavioral progression or behavioral depression may happen in purchase process (Alderfer, 1972). In practice, we find the fitness between product attributes and partner’s brand awareness will affect the result of brand alliance. The finding implies that ingredient firms which have great brand equity in B2B market may have low equity in B2C market. Second, the weight of car brand will be more important when asymmetric information exists. Third, the ingredient firms which have great equity in B2B market and low awareness in B2C market have the motive to cooperate with private label brand firms. Fourth, there are some niches in Taiwanese SUV market. Fifth, branding can’t success without self-audit. Sixth, delivering the appropriate and correct information to consumers is one of the most important things of value creation. Seventh, strategy is the nature of branding, so it will be very hard to brand without strategic planning.

Parts made out of titanium alloys demonstrate anisotropic mechanical properties when manufactured by electron beam melting, an emerging additive manufacturing technique. Understanding the process history dependent heterogeneous microstructure, and its effect on mechanical properties is crucial in determining the performance of additively manufactured titanium alloys as the mechanical behavior heavily relies on the underlying microstructural features. This thesis work focuses on combined experimental and computational techniques for microstructure characterization, synthetic microstructure generation, mechanical property measurement, and mechanical behavior modeling of polycrystalline materials, with special focus on dual phase titanium alloys. Macroscopic mechanical property measurements and multi-modal microstructure characterizations (high energy X-ray diffraction, computed tomography and optical microscopy) are performed on additively manufactured Ti-6Al-4V parts, revealing the heterogeneity of the microstructure and properties with respect to the build height. Because characterizing and testing every location within a build is not practical, a computational methodology is established in order to reduce the time and cost spent on microstructure-property database creation. First a statistical volume element size is determined for the Fast Fourier Transform based micromechanical modeling technique through a sensitivity study performed on an experimental Ni-based superalloy and syntheticW, Cu, Ni and Ti structures, showing that as the contrast of properties (e.g., texture, field localization, anisotropy, rate-sensitivity) increases, so does the minimum simulation domain size requirement. In all deformation regimes a minimum volume element is defined for both single and dual phase materials. The database is then expanded by generating statistically representative Ti structures which are modified for features of interest, e.g., lath thickness, grain size and orientation distribution, to be used in spectral full-field micromechanical modeling. The relative effect of the chosen microstructural features is quantified through comparisons of average and local field distributions. Fast Fourier transform based technique, being a spectral, full-field deformation modeling tool, is shown to be capable of capturing the relative contribution from varying microstructural features such as phase fractions, grain morphology/ size and texture on the overall mechanical properties as the results indicate that the mean field behavior is predominantly controlled by the alpha phase fraction and the prior beta phase orientation.