Phase stability of microfine Mo2C phases in high vacuums

Abstract

The phase stability of Mo2C in high vacuums was investigated be means of X-ray powder diffraction (XRD) analysis. Two types of Mo2C were considered: as-received commercial Mo2C powders and wet ball-milled Mo2C powders. Assuming that the decomposition of Mo2C to Mo was due to oxidation, the reaction should in the main proceed from the surface to the center of the briquette during decomposition. It was demonstrated that the decomposition was indeed inched from the surface to the center of the briquette. Similar observations were made for the rest of the briquettes showing sign of decomposition.