The in-flight modification of titanium carbide powders was carried out in radio-frequency (rf) inductively coupled plasmas. The powders were partially melted and evaporated, and then subjected to modifications in morphology, size, and chemical composition. Both the Ar–H2 and Ar–N2 plasma treatments induced the formation of carbon-site vacancies in titanium carbide. The mixing of NH3 to Ar–H2 plasma at the plasma tail, and the Ar–N2 plasma treatment resulted in the partial substitution of carbon by nitrogen. The variation in physical and chemical modification was discussed compared with the predictions by the thermochemical analysis, and the numerically obtained heat transfer of our preceding paper.

Modeling of TiC powder behavior in Ar–H2 and Ar–N2 RF thermal plasmas has been performed as well as the numerical analysis of the plasma fields to investigate the plasma/powders interaction. The heat transfer rate from the plasma to the powders decreases with increasing the powder feed rate and with decreasing the plasma pressure, because of the significant local cooling owing to the presence of the injected powders. These results agree fairly well with the experimental results of our following paper. The modeling herein gives guidance for the rational design of new material processing using thermal plasmas.