Synthesis of copper–niobium carbide composite powder by in situ processing

Abstract

Abstract The in situ formation of niobium carbide (NbC) particles was investigated during mechanical alloying process as well as subsequent heat-treatment. Initial starting powders of Cu, Nb and C were used with a composition of Cu–40 wt% Nb–10 wt% C which was corresponding to Cu–40 vol% NbC. A mixture of this powder system was milled in an argon atmosphere for four different durations, i.e., 15 h, 31 h, 42 h and 54 h. X-ray diffraction was used to verify the formation of NbC. No NbC was formed after the milling process. The in situ formation of NbC in a copper matrix only took place after heat-treatment at 900 °C. Longer milling time resulted in the formation of NbC phase with more intense X-ray diffraction peaks due to powder refinement.