by Benjamin Young1, Joseph Heelan1,Sean Langan1,Matthew Siopis2,Caitlin Walde1,* andAaron Birt1
1 Solvus Global, Worcester, MA 01605, USA 2US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, MD 21005, USA *Author to whom correspondence should be addressed.
Academic Editor: Francisco Paula Gómez Cuevas
Metals 2021, 11(5), 720; https://doi.org/10.3390/met11050720
Received: 31 March 2021 / Revised: 19 April 2021 / Accepted: 23 April 2021 / Published: 27 April 2021
(This article belongs to the Special Issue Metals Powders 2020: Synthesis and Processing)
Abstract
Additive manufacturing is a rapidly expanding field, encompassing many methods to manufacture parts and coatings with a wide variety of feedstock. Metal powders are one such feedstock, with a range of compositions and morphologies. Understanding subtle changes in the feedstock is critical to ensure successful consolidation and quality control of both the feedstock and manufactured part. Current standards lack the ability to finely distinguish almost acceptable powders from barely acceptable ones. Here, novel means of powder feedstock characterization for quality control are demonstrated for the solid-state AM process of cold spray, though similar methods may be extrapolated to other additive methods as well. These characterization methods aim to capture the physics of the process, which in cold spray consists of high strain rate deformation of solid-state feedstock. To capture this, in this effort powder compaction was evaluated via rapidly applied loads, flowability of otherwise non-flowable powders was evaluated with the addition of vibration, and powder electrical resistivity was evaluated through compaction between two electrodes. Several powders, including aluminum alloys, chromium, and cermet composites, were evaluated in this effort, with each case study demonstrating the need for non-traditional characterization metrics as a means of quality control and classification of these materials. View Full-Text
To view the Novel Characterization Techniques for Additive Manufacturing Powder Feedstock article in its entirety, please visit https://www.mdpi.com/2075-4701/11/5/720 or download the MDPI Metals Journal pdf file for the full-text article.