Effect of Process on Microstructure and Mechanical Properties of TA5 Alloy Sheets

The effects of processing, annealing and thermal orthosis on microstructure and mechanical properties of TA5 alloy sheets are investigated. The results show that the slab deforms at 150℃ above the phase transition point during the second fire forging, resulting in the coarsening of the structure. The coarsened structure is fibrous and of very high strength, with little plastic change. The microstructure of sheets reversing rolled is uniformly exquiaxed, the size of the recrystallized grain increases, the strength declines and the plasticity rises obviously. With the increase of finishing rolling temperature, the homogeneous growth of the recrystallized grains is obvious, which reduces the strength and increase the plasticity. In order to alleviate the influence of thermal orthosis on microstructure and mechanical properties of the sheets, the annealing temperature shall be higher than that of the material in the thermal orthosis process. After the second or the third thermal orthosis, the unevenness can reach 2~3 mm/m, and the mechanical properties at room temperature are almost unchanged.