Deformation Behavior of Ti-5. 6Al-4. 8Sn-2. 0Zr-1. 0Mo-0. 35Si-0. 85Nd Alloy in β/Quasi-β Forging Process

The hot deformation behavior of Ti-5. 6Al-4. 8Sn-2. 0Zr-l. 0Mo-0. 35Si-0. 85Nd alloy in β/quasi-β forging process was studied using isothermal compression tests over temperature range from 1040 °C to 1100 °C and strain rates form 0. 001 s−1 to 70 s−1. The results show that the flow stress and microstructure are sensitive to thermomechanical parameters. The processing maps based on the dynamic materials model at strain of 0. 3 and 0. 7 were established. The optimum deformation thermomechanical parameters at a strain of 0. 7 have two regions that exhibit the peak of power dissipation efficiency. One is the region of 1062-1100 °C and 10−3-10−1.5 s−1; and another which represents dynamic recrystallization is 1040-1045 °C and 10−18-10−09 s−1. The instable region is located where the strain rate is larger than 1 s−1 which corresponds to the mechanical instability.