Single Particle Impact Analysis to Improve Cold Sprayability of High Entropy Alloy

High Entropy Alloys (HEA) are materials consisting of five or more elements and are desirable in engineering for their great strength-ductility combinations, corrosion resistance and radiation resistance. The solid state, low temperature operation in cold spray is very suitable for the production of HEA's as it prevents phase change of the powder [1], but it is also complicated due to the small window of deposition when velocity, powder size and temperature are in the right range [2]. In this work a novel approach was undertaken utilizing single particle ejection to analyse the high velocity impact between the HEA’s and the substrate. Pairing the in-situ data with Scanning Electron Microscopy (SEM) and Electron Backscatter Diffraction (EBSD), a better understanding of the deposition process was obtained. This information can now be used to optimize the cold spray deposition of this HEA, improving deposition efficiency, and reducing the overall porosity. [1] Shuo Yin et al. Deposition of FeCoNiCrMn high entropy alloy (HEA) coating via cold spraying. Journal of Materials Sciences and Technology, 35(6):1003, June 2019. [2] Shuai Feng et al. Cold Spray Additive Manufacturing of CoCrFeNiMn High-Entropy Alloy: Process Development, Microstructure, and Mechanical Properties. Journal of Thermal Spray Technology, 31:1–10, March 2022.