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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Additive manufacturing can bring several advantages in tooling applications especially hot working tooling as high pressure die casting. Printing of conformal cooling channels can lead to improved cooling and faster solidification, which, in turn, can possibly result in better quality of the cast part. However, few studies on advantages of additive manufactured tools in high pressure die casting are published.The aim of this study was to investigate and quantify the effect of conformal cooling on microstructure and mechanical properties of high pressure die cast aluminum alloy. Two tools each consisting of two die inserts were produced with and without conformal channels using additive manufacturing. Both tools were used in die casting of aluminum alloy. Aluminum specimens were then characterized microstructurally in light optical microscope for secondary arm spacing measurements and subjected to tensile and hardness testing. Cooling behavior of different inserts was studied with a thermal camera and by monitoring the temperature change of cooling oil during casting. Surface roughness of die inserts was measured with profilometer before and after casting.Thermal imaging of temperature as a function of time and temperature change of oil during casting cycle indicated that conformal insert had faster cooling and lower temperature compared to conventional insert. However, thermal imaging of temperature after each shot in a certain point of time showed higher maximum and minimum temperature on conformal die surface but no significant difference in normalized temperature gradient compared to the conventional insert.The average secondary dendrite arm spacing values were fairly similar for samples from conventional and conformal inserts, while more specimens from conventional insert demonstrated coarser structure. Slower cooling in conventional insert could result in the coarser secondary dendrite arm spacing.Tensile strength and hardness testing revealed no significant difference in mechanical properties of the specimens cast in conventional and conformal die inserts. However, reduced deviations in hardness was observed for samples cast with conformal insert. This is in agreement with secondary dendrite arm spacing measurements indicating improved cooling with conformal insert.Surface roughness measurement showed small wear of the inserts. More castings are needed to observe a possible difference in wear between the conventional and conformal inserts.Small observed differences in cooling rate and secondary arm spacing did not result in evident difference in mechanical properties of the aluminum alloy but the variation in properties were reduced for samples cast with conformal cooling. Future work may include more accurate measurement of cooling behavior with a thermocouple printed into the die insert, casting of thicker specimen for porosity evaluation and fatigue testing and longer casting series to evaluate the influence of conformal cooling on tool wear.