Structure and properties of Mo–9Si–8B alloy fabricated by casting

Abstract

This article discusses the microstructure and mechanical properties under compression and resistance against oxidation of Mo–9Si–8B (at %) alloy fabricated by casting. Despite generation of coarse dendritic structure, the as-cast alloy demonstrates excellent high-temperature strength: the alloy yield strength at 1200°C is 700 MPa, and the maximum compression strength is 750 MPa, which is significantly higher than the strength properties at this temperature of the top quality heat-resistant alloys on the basis of nickel. The article considers possible improvements of the alloy resistance against oxidation by disintegrating the dendritic structure and obtaining a fine-grained structure, which promotes a more uniform distribution in the bulk of the matrix phase and disperse intermetallic phases.