Effect of powder surface state on microstructure and tensile properties of a novel near α-Ti alloy using hot isostatic pressing

In this work, a novel near α high temperature titanium alloy powder compact was prepared through hot isostatic pressing (HIP). The effect of powder surface state on microstructure and tensile properties of hot isostatically pressed (HIPed) powder compacts were investigated. The results show that the tensile properties of powder compact HIPed from short-term stored powder are comparable to those of wrought state and the commercial IMI 829 alloys. The relationship between the thickness of oxide layer on the powder surface and powder storage time has been confirmed. The long-term stored powder will increase the microstructural inhomogeneity and reduce the elongation of HIPed powder compacts. The relevant mechanisms were discussed based on the evolutions of powder surface state during powder storage and HIP processes.