Construction of a Predictive Model for Dynamic and Static Recrystallization Kinetics of Tc21 Titanium Alloy

Abstract

Abstract: In this study, hot compression experiments were conducted on cast TC21 titanium alloy using a Gleeble-1500D thermal simulation compression tester, and the hot-compressed specimens were heat-treated. By analyzing the data obtained after hot compression of the cast TC21 titanium alloy, a thermal processing map was constructed for a strain of 0.8, and the processing window was optimized. The microstructure of the alloy after hot compression experiments and heat treatment was analyzed, and the microstructure evolution law of the cast TC21 titanium alloy was studied. The analysis of the tissue evolution law, combined with the purpose of establishing a dynamic and static recrystallization prediction model, established the dynamic and static recrystallization volume fraction as a function of heat deformation parameters. The results show that the optimal processing window for cast TC21 titanium alloy is: deformation temperature in the range of 1373K-1423K and strain rate of 0.1s-1; The increase in deformation volume and deformation temperature both favor recrystallization and make the recrystallization volume fraction increase, but the increase in strain rate will inhibit the increase in recrystallization degree to some extent; The dynamic and static recrystallization equations for the cast TC21 titanium alloy at different temperatures were fitted:1273K:,1373K:,1473K: .

Keywords: Cast TC21 titanium alloy, Thermal compression, Processing diagram, Dynamic and static recrystallization, Predictive Model