Study on the organization and properties of high-strength Ti-Zr-Mo-Al alloys

Abstract

Abstract This work investigated the effect of the heat treatment mechanism on the mechanical properties and microstructure of the metastable β titanium alloy (Ti-16.3Zr-13.6Mo-6Al-1.6Cu-0.6Ni). The results reveal that the α phase morphology at the grain boundary of the as-cast changes from continuous distribution to discontinuous distribution after heat treatment at 900°C/12 h. When the solution temperature is raised to 1200°C/12 h, the α phase shows spherical distribution at the grain boundary. At this moment, the yield strength reaches about 1009 MPa, and the tensile strength reaches about 1188 MPa. In addition, the elongation is about 2.3%. Then the alloys were aged at 450°C from 4 h to 8 h after solution at 1200°C/12 h. In the aging process, the plastic deformation capacity is further reduced because a point-like α phase was precipitated in the alloy. However, the compressive strength was improved. From aging treatment at 450°C/6 h, the compressive yield strength reached about 1584 MPa, and the compressive strength reached about 2034 MPa. However, the compressive plasticity strain is only 2.1%.