Reactive sintering of molybdenum alumino-silicide and its oxidation resistance

Abstract

An intermetallic compound, molybdenum alumino-silicide, MoAl_xSi_2−x, is produced from a mixture of molybdenum, aluminum and silicon powders by using a pseudo-hot-isostatic-pressing (PHIP) process and a reactive sintering method. The mechanical properties at room temperature and oxidation behavior at 773 K and 1500 K are investigated. The increase in the PHIP pressure leads to a remarkable increase in density and hardness of the alumino-silicide. The increase in aluminum content of the alumino-silicide leads to a slight increase in density, but it does not affect the hardness. The increase in aluminum content of the alumino-silicide dramatically improves its oxidation resistance.