Deformation behavior and microstructure evolution in multistage hot working of TA15 titanium alloy: on the role of recrystallization
- 784 Downloads
Interrupted compression tests of TA15 titanium alloy with initially equiaxed microstructure were carried out at deformation temperatures between 1173 to 1273 K and strain rates between 0.001 to 0.1 s−1 to investigate the deformation behavior and microstructure evolution under multistage deformation. The TA15 alloy exhibits significant flow softening in both β and (α + β) working. It is found that the flow softening relates to dynamic recrystallization of β phases under current experimental conditions. In multistage β working, metadynamic recrystallization is the main softening mechanism during inter-pass holding. The grain refinement by metadynamic recrystallization leads to the decrease in peak stress upon reloading. In multistage (α + β) working, static recrystallization is the main softening mechanism during inter-pass holding. The static recrystallization kinetics increases with temperature and strain rate. The inter-pass holding has little influence on the morphology of the primary α phases. The β grain size is determined by spacing of primary α phases, which is more affected by working temperature but less dependent on strain rate and inter-pass holding time.
KeywordsMultistage deformation TA15 titanium alloy Flow stress Microstructure Recrystallization
The authors would like to gratefully acknowledge the support of Natural Science Foundation for Key Program of China (No. 50935007) and National Basic Research Program of China (No. 2010CB731701).
- 30.Hunphreys FJ, Hatherly M (2004) Recrystallization and related annealing phenomena, 2nd edn. Pergamon Press, OxfordGoogle Scholar