Microstructural and Micromechanical Characterization of Feedstock for Cold Spray Additive Manufacturing and Processing

Abstract

Due to the processes solid-state nature, cold gas-dynamic spray metal additive manufacturing may be considered microstructurally and micromechanically retentive, such that properties of the feedstock material are refined and partially retained, influencing component performance. As a result, cold spray processing enables unique freedoms regarding feedstock, which can be pre-processed using chemical, thermal, and mechanical treatments to produce powder properties that achieve finely controlled consolidations with application-specific behaviors. Given such features of the cold spray process, the present review article is concerned with the through-process integration of mechanically and microstructurally characterized feedstocks for optimizable cold spray metal additive manufacturing. Therefore, in this paper, we consider how nanoindentation (dynamic, static, and quasi-static) was coupled with microstructural characterization for experimental feedstock evaluation, testing, and characterization. Atomized aluminum alloys, atomized stainless steel, and copper feedstocks, among others, were considered. Accordingly, the review validates how microparticle feedstock pre-processing and characterization in cold spray metal additive manufacturing and processing lead to controllable component performance and properties.