The Effect of Annealing Heat Treatment on the Microstructure and Macroscopic Properties of Kinetic-Sprayed Ta Coating Layer

Abstract

The effect of annealing heat treatment on the properties of high-density tantalum coating layer produced by the kinetic spray process was investigated. Pure Ta powder with an average particle size of 24.35μm and irregular shape was used to produce the coating layer through kinetic spray process. The annealing heat treatments of tantalum coating layers were applied for an hour in an Ar gas atmosphere under temperatures of 800°C, 900°C, 1000°C, and 1100°C. The manufactured coating layers have hardness and porosity of 270 Hv and 0.28%, respectively, showing even higher density levels than the kinetic-sprayed Ta coating layers reported to date. As the annealing temperature increased, the hardness value of the coating layer reduced from 270 Hv to 183 Hv and the porosity was verified to have decreased from 0.28% to 0.18%. The result of the additional XPS analysis confirmed that the phase generated between particle interfaces with heat treatment was Ta2O5 oxide. Based on these results, improving methods to dense the Tantalum coating layer with kinetic spray process was considered.