Ultra-high temperature Mo–Si–B alloys — Synthesis, microstructural and mechanical characterization

Molybdenum boron silicides containing between 18 and 31 vol.% α-Mo are prepared by reactive hot-pressing from Mo–Si–B powder mixtures. Their microstructures and mechanical properties are investigated. The multiphase alloys consist of Mo3Si, Mo5SiB2 and discontinuous α-Mo. The results demonstrate that the volume fraction of α-Mo and B content exerts a significant effect on the flexural strength and fracture toughness of the multiphase alloys.