The interfacial β0 phase strengthening the creep properties of powder hot isostatic pressing γ-TiAl alloy

Abstract

Interfacial β0 phase strengthening on the creep properties of TNM alloy has been investigated. The initial fully lamellar microstructure with fine-dispersed interfacial β0 phase was fabricated by powder hot isostatic pressing (P-HIP) and then carried out ageing treatment. The results indicated that the aged condition presented better microstructural stability and excellent creep resistance than the P-HIPed condition. Moreover, the ω phase precipitated within the β0 phase by stress-inducing. The β0/β0(ω) phase was not only effectively restricted the dislocation motion, twins and stacking faults propagation, but also delayed the α2 lamellae decomposition to maintain the integrity of the fully lamellar structure.

Keywords

• TiAl alloy
• β0 phase
• hot isostatic pressing
• creep
• phase transformation