Research on microstructure and properties of Ti-15Mo-3Al alloy with high oxygen content

Abstract In this paper, the near-equilibrium microstructure and properties of Ti-15Mo-3Al-1O alloy treated by solid solution at different temperatures were systematically studied. The microstructure of the alloy was observed and analyzed by optical microscope (OM), scanning electron microscope (SEM) and x-ray diffraction (XRD). The results indicated that the microstructure composed of equiaxial β grains without any precipitate was detected after solution treatment at 1,100 °C/4 h and 1,200 °C/2 h. In addition, the lattice parameters of β phase increased gradually with the increasing of solution temperature. Hardness and room temperature compression test were performed using Vickers hardness tester and universal testing machine. The results showed that the alloy subjected to solution treatment exhibited a high level of hardness value, with the minimum value of 367HV; the alloy subjected to solution treatment at 800 °C/2 h exhibited high compressive yield strength, with the maximum value of nearly 1,650 MPa; the alloy subjected to solution treatment at 1,100 °C/2 h and 1,200 °C/2 h exhibited excellent compressive ductility (The specimens were not crushed, the strain δ > 50%) with high compressive yield strength (YS > 1,100Mpa).