Crystallographic Texture and Yield Strength Anisotropy of TA1 Pure Titanium Cold Rolled Sheet After Annealing

A 2.0 mm thick TA1 industrial pure titanium sheet was cold-rolled with a reduction rate of 75%, and annealed at 760 ℃ for different time periods （30, 60, 120 s） and different temperatures （790, 820 ℃） for 60 s. The microstructure, texture and yield strength of the annealed pure titanium sheet were studied by electron backscatter diffraction and tensile test. The relationship between texture and planar anisotropy of yield strength was analyzed by calculating the average orientation factor. The results show that after annealing, the cold-rolled textures in TA1 industrial pure titanium sheet was partially retained, and new textures, of 0113〈7520〉 and 1125〈4510〉 pyramidal textures, and 0113 and 1125 plane textures were formed. The yield strength of the annealed pure titanium sheet exhibited planar anisotropy, and the yield strength decreased in the order: transverse direction （TD） > 45° direction > rolling direction （RD）. With the extension of annealing time period, the content of 0001 basal texture and 0113〈7520〉 pyramidal texture decreased, the content of 1125〈4510〉 pyramidal texture increased, the difference value in the average orientation factors between the RD and the TD increased, and the anisotropy of yield strength between the two directions increased. With the increase of annealing temperature, the content of 0001 basal texture and 1125〈4510〉 pyramidal texture decreased first and then increased, 0113〈7520〉 pyramidal texture increased first and then decreased, the difference value in the average orientation factors between the RD and the TD increased first and then decreased, and the anisotropy of yield strength between the two directions increased first and then decreased. The existence of 0001 basal texture weakened the anisotropy of yield strength, and the existence of 0113〈7520〉 and 1125〈4510〉 pyramidal textures enhanced the anisotropy of yield strength.