Evaluation for Creep Properties of Ti-43Al-5V-4Nb at 600°C

Abstract

The 3rd generation wrought TiAl alloys are expected to be applied to high-temperature equipment because those have higher specific strength than Ni-based superalloys and toughness due to β phase. In this study, creep properties of Ti-43Al-5V-4Nb with improved forgeability by adding V and Nb were investigated. The relationship between the minimum creep rate and the rupture time could be approximated according to the Monkman-Grant law. This means the rupture time can be estimated from the behavior up to the secondary creep. The cracking modes changed from inter-lamellar to trans-lamellar and duplex cracking with crack growth. The generation of micro cracks on the surface did not depend on the microstructure.