Effect of Solution and Aging Treatment on Microstructure and Properties of TC4 Titanium Alloy Hot-Rolled Sheet by Sponge Titanium /Electrolytic Titanium Melting

Abstract:

In this paper, sponge titanium and electrolytic titanium are used as raw materials for melting TC4 titanium alloy. The smelted ingot is subjected to hot rolling and solution aging treatment. The microstructure and properties of TC4 titanium alloy sheet rolled from ingots of different raw materials after different solid solution aging treatments were studied. The results show that the α → β transition of sponge titanium TC4 and electrolytic titanium TC4 titanium alloys is an endothermic process. When the sponge titanium TC4 titanium alloy is solid-solved at a temperature exceeding the transformation point temperature, its structure is Weiss-structure, and the other structures under the solid-solution aging condition are all bimorphic. After solid solution aging treatment, the tensile strength of sponge titanium TC4 increased first and then decreased with the increase of the solution temperature, and the elongation continued to decrease. The tensile strength of electrolytic titanium TC4 increases with increasing solution temperature, while the elongation continues to decrease. Both of them obtained the best comprehensive mechanical properties after solid solution holding at 890℃ for 30min and 550℃ for 3h. Compared with sponge titanium TC4, the electrolytic titanium TC4 has a more significant increase in strength and hardness after solid solution aging treatment.