Flow behavior and processing map of PM Ti−47Al−2Cr−0.2Mo alloy
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,
Changsha 410083, China)
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,
Changsha 410083, China)
Abstract: The flow stress features of PM Ti−47Al−2Cr−0.2Mo alloy were studied by isothermal compression in the temperature range from 1000 to 1150 °C with strain rates of 0.001−1 s−1 on Gleeble−1500 thermo-simulation machine. The results show that the deformation temperature and strain rate have obvious effects on the flow characteristic, and the flow stress increases with increasing strain rate and decreasing temperature. The processing maps under different deformation conditions were established. The processing maps of this alloy are sensitive to strains. The processing map at the strain of 0.5 exhibits two suitable deformation domains of 1000−1050 °C at 0.001−0.05 s−1 and 1050−1125 °C at 0.01−0.1 s−1. The optimum parameters for hot working of the alloy are deformation temperature of 1000 °C and strain rate of 0.001 s−1 according to the processing map and microstructure at true strain of 0.5.
Key words: powder metallurgy; TiAl based alloy; hot compression deformation; processing map