Investigation On The Deformation Processing And Relationship Between Microstructure And Property Of TC4 Alloy Ring Part

In this paper, the influence of forging and rolling parameters on microstructure and mechanical properties of TC4 annular products was investigated. And its affected mechanisms were analyzed thoroughly based on the experimental data obtained from various shaping temperatures, processroutes and heat treatment methods. By comparing the forging temperatures of 900? and 970?, it is found that the duplex microstructure was observed at low shaping temperatures(that is the composition of 40 percent ? phase with equiaxed grain and the remained ? phase with lamellar structure), which provided high instantaneous intensity at elevated temperature. Whereas the instantaneous properties at elevated temperature of the products were relatively low, attribute to the nearly equiaxed grains, when deformed at high temperature. And the accept ability was on the low level. Therefore, with the consideration of improvement of room-temperature strength and high-temperature strength, the last process of shaping temperature should be decreased.According to microstructural observation, both high and low distinguished microstructure of freeforging products and rolling products agreed with standard requirements. Compared with the free forging, the rolling products possessed a more neat appearance and high quality surface properties. In addition, its room temperature tensile strength and yield strength were increased, while the plasticity is slightly lower and high temperature instantaneous intensity change is not obvious. Even though both freeforging and rolling products exhibited similar properties, the rolling products can significantly reduce forming steps, save energy, and improve the efficiency of production.Within the scope of heat treatment standard system, heat treatment temperatures and holding times had significant effect on the microstructure and mechanical properties of TC4 ring forgings. The grain size and content of the primary alpha would be changed during heat treatment, which improves the performance of the alloy of forgings under various heat treatment temperatures and times. So the heat treatment by changing the fraction of primary alpha and grain size to change the performance of TC4 alloy.