On the Additive Manufacturing of Inconel 939 - Analysis of Microstructure and ReDevelopment of Heat Treatment

Paper i proceeding, 2020

Inconel-939 is a Ni-base superalloy developed for service up to 850°C and is widely used in hot-sections of industrial gas turbine engines. The potential for improved hot-gas-path component design through the geometric complexity to be realized by additive manufacturing (AM) makes the processing of Inconel-939 by laser-powder bed fusion an attractive prospect. However, the complexity and length of conventional Inconel-939 heat treatment, as well as the different starting microstructure, necessitate a modified heat treatment for the AM alloy. The microstructures and mechanical properties resulting from these treatments were characterized and compared. The difference in room temperature and elevated temperature mechanical performance is discussed in light of the performance of the cast alloy and the evolution of the microstructure.