Effect of Annealing Temperature on Microstructure and Mechanical Property of High Purity Titanium Cold Rolled Plate

The cold rolled high purity (99.995%) titanium plate with 60% reduction is annealed at different temperatures. The microstructure of the high-purity titanium plate is characterized by EBSD technology, and the tensile and hardness tests are carried out. The results show that with the increase of annealing temperature, the tensile strength and hardness of the high-purity titanium plate decrease continuously, and the elongation increases. After annealing at 600 ℃ for 10 minutes, the elongation of the plate reaches (74.6±5.0)%, and the tensile strength reaches (217±2) MPa. The microstructure shows that the grains have been completely transformed into equiaxed grains without distortion after being annealed at 600 ℃ for 10 minutes, and that the KAM value is reduced to 0.16°, indicating that there is almost no local strain and stored energy in the plate at this moment. The reason is that with the increase of annealing temperature, the dislocation density of the grain decreases, and the softening effect increases.