|RELATING MICROSTRUCTURE TO PROCESS VARIABLES IN BEAM-BASED ADDITIVE MANUFACTURING OF INCONEL 718|
|Master of Science (MS), Wright State University, 2014, Mechanical Engineering|
The advancement of laser or electron beam-based additive manufacturing requires the ability to control solidification microstructure. Previous work combined analytical point source solutions and nonlinear thermal finite element analysis (FEA) to explore the effects of deposition process variables on Ti-6Al-4V solidification microstructure. The current work seeks to extend the approach to Inconel 718, with the addition of Cellular Automaton-Finite Element (CAFE) models. Numerical data from finite element results are extracted in order to calculate accurate melt pool geometry, thus leading to corresponding cooling rates and thermal gradients. The CAFE models are used to simulate grain grown and nucleation, providing a link between additive manufacturing process variables (beam power/velocity) and solidification microstructure. Ultimately, a comparison of results between Ti-6Al-4V and Inconel 718 is expected to lay the ground work for the integrated control of melt pool geometry and microstructure in other alloys.
Committee: Nathan Klingbeil, Ph.D. (Advisor); Raghavan Srinivasan, Ph.D., P.E. (Committee Member); Jaimie Tiley, Ph.D. (Committee Member)
Aerospace Engineering; Aerospace Materials; Engineering; Materials Science; Mechanical Engineering
Keywords: Additive Manufacturing Beam Laser FEA CAFE ProCAST Inconel 718 Ti-6Al-4V melt pool process variables microstructure power velocity gamma prime 3D printing Rosenthal