Simulation of Additive Manufacturing Process Physics and Properties in Powder Bed Electron-Beam Melting of Ti-6Al-4V

Abstract

Electron-Beam Melting (EBM) is a novel additive manufacturing process that is capable of producing production-quality parts. However, part quality and microstructure are still highly variable. In order to improve the ability to develop better process parameters, experimental and numerical methods were preliminarily developed to better understand the process physics and phenomena. The state of the art in EBM process and process simulation is discussed and areas in need of further development are identified. An infrared camera is calibrated and used to attempt to measure temperatures in situ. A coupled computational fluid dynamics-thermal model is implemented in ANSYS Fluent in order to simulate the meltpool dynamics and heat transfer. This modeling approach allows for accurate resolution of process physics while avoiding excessive computational cost or time. Predicted and experimental melt pool topologies are compared for differing process and component conditions and with similar data. The effects of part geometry and process parameters on solidification rates and other microstructural characteristics are discussed and compared with experimental data. The experimental and numerical data from this work is compared with similar data from the literature and future improvements and developments are discussed.