Reactive Plasma Spraying of Super-Hard Ta-Hf-W-C Single-Phase Solid Solution Coating

A W supersaturated Ta-Hf-W-C single-phase solid solution coating is successfully prepared by a reactive plasma spraying. The reaction process of TaC-HfC-WC-C composite powder during induction plasma spheroidization (IPS) and vacuum plasma spraying (VPS) are described. Compared with the direct spraying, the coating made by IPS-VPS multi-stage plasma heating process has better density and composition uniformity. The highest hardness obtained by...