Metal Additive Manufacturing with Minimal Post Processing (MaMMPP) (18-RD-116)

Metal Additive Manufacturing (AM) research has typically addressed understanding how to maximize performance for an AM material, taking into account microstructural anisotropy, residual stress, defects (such as pores and lack of fusion defects), and surface finish. Optimizing a part then requires significant post processing such as hot isostatic pressing (HIP), heat treatment and surface finishing. The goal of this project is to develop an alloy for AM that can have consistent properties with minimal post processing. UES, Inc. will work with the Pennsylvania State University to identify the most appropriate machine, develop an iron-base alloy optimized for minimal post processing, and confirm the suitability for deployment. Alloy optimization will be both theoretical (using CALPHAD for alloy design) and based on measurements of strength and microstructural isotropy. While initial work will use directed energy deposition technology, the program seeks to identify a machine agnostic source material for those AM machines most appropriate for military deployment. For example, binder jet deposition, such as the Ex-One machines, require metal powder feedstock blended with a polymer binder that is subsequently pyrolyzed. This technology for producing a dense metal part is now relatively mature, but alloys optimized for minimal post processing are the focus here.