Characteristics of hot compression behavior of Ti–6.5Al–3.5Mo–1.5Zr–0.3Si alloy with an equiaxed microstructure

Abstract

The hot compression behavior of Ti–6.5Al–3.5Mo–1.5Zr–0.3Si alloy with an equiaxed microstructure was examined in the temperature range of 900–1060 °C and strain rate range of 0.001–10 s −1. The dynamic recrystallization (DRX), flow instability and texture of compressed Ti alloy are characterized by the processing maps and EBSD. The stress–strain curves of Ti alloys show that the continuous flow softening occurs, while the broad oscillations induced by adiabatic shear bands exist above strain rates of 1.0 s −1. The processing maps exhibit two DRX domains: α phase DRX domain in the range of 900–980 °C and 0.001–0.1 s −1, and the β phase DRX domain in the range of 1000–1060 °C and 0.01–1.0 s −1. It is also found that the instable deformation region increases with strain increasing. In addition, EBSD results exhibit that DRX can cause the low angle boundaries (LABs) to decrease and the high angle boundaries (HABs) to increase in the α + β region.