A review on ICP powder plasma spheroidization process parameters

Powder particles with spherical geometries have been found to result in better powder performance in different industries, especially Additive Manufacturing (AM), by fabricating more dense powder layers that consequently result in more desirable part properties with less defects. Plasma spheroidization process has shown an excellent capability in enhancing particle geometries of powders from a variety of materials, particle size distributions, and arbitrary initial particle geometries. The current review paper summarizes the previous conducted work on plasma spheroidization process to determine the effect of its process parameters on powder characteristics. The spheroidization process parameters, including powder feed rate, central, carrier, and sheath gas flow rates, gas mixtures, power, and chamber pressure are individually discussed. Also, the impact of these process parameters on powder characteristics, such as particle size distribution, particle trajectories, chemical impurity, microstructure, porosity, flowability, and densities are reviewed. A tradeoff among process parameters, spheroidization ratio, and evaporation rate was observed. Depending on particle size and material melting point, increasing particle residence time in exposure to plasma first increased and then decreased the spheroidization ratio overall. •A comprehensive review on powder plasma spheroidization process.•Effects of spheroidization parameters on powder characteristics have been summarized.•Improvement of powder performance through reshaping irregular particles to spheres.•A tradeoff exists among spheroidization parameters, spheroidization, and evaporation.•Increasing residence time first increased and then decreased spheroidization overall.