Microstructure Variations and Creep Properties of Novel High Temperature V-Si-B Materials

Our current understanding of the properties of V-Si-B alloys produced by a powder and an ingot metallurgy route is reported. This novel group of materials with high melting points above 1900°C and a low density of 5.21–5.85 g/cm3 has been identified as a potential alloy system for applications at temperatures up to 1000°C. A powder metallurgical V-9Si-13B alloy with a three-phase microstructure is introduced and characterized in terms of creep behavior in the as-received and annealed state. Annealing at 1300°C leads to grain growth and improved creep resistance. For comparison, the same alloy composition is produced via arc-melting, yielding a coarser microstructure. Another powder metallurgically processed alloy having the nominal composition of the phase V5SiB2 is comparably assessed. Compression creep tests at temperatures between 900°C and 1050°C demonstrate that these novel alloys are competitive compared to Al-Ti materials and Ni-Co superalloys.