Compressive deformation behavior of a near-beta titanium alloy

This paper documents an investigation into the compressive deformation behavior of a solution treated near beta titanium alloy. The mechanical testing was carried out at strain rates of 10(-3) S(-1) and 10(3) S(-1) by a numerically controlled hydraulic MTS machine and a Split Hopkinson Pressure Bar test system, respectively. The results show that the work hardening characteristics of the titanium alloy were not significantly influenced by strain rate. Further, the flow stress followed a similar trend in both the low and high strain rate tests because of the formation of a martensitic alpha '' phase. The flow stress at high strain rate (10(3) S(-1)) was slightly lower than that in the quasi-static condition (10(-3) S(-1)). The hardness in the beta phase was higher than that in the martensitic alpha '' phase. Also, the lowest hardness was located in the adiabatic shear bands (ASBs) which were associated with high strain rate deformation. Electron Backscatter Diffraction (EBSD) mapping confirmed the presence of the alpha '' phase in deformed specimens at both strain rates. The fracture characteristics were observed using scanning electron microscopy (SEM). (C) 2011 Elsevier Ltd. All rights reserved