Heat treatment method for TC4（GR5） and TC11 titanium alloy forgings

      It is reported that the working time under 500℃ can reach 6000h and up to 3000h at 550℃. Therefore, TC4（GR5） titanium alloy is an ideal thermal strength titanium alloy for generating ideas, which can be used for manufacturing aerospace generating ideas compressor parts. The alloy can be processed into forgings, bars, die forgings and other forms of products.　

      The effects of different solution temperatures and cooling methods on the microstructure and function of BT25 titanium alloy forgings were studied. The results show that the microstructure of air-cooled is finer than that of furnace cooled at the same solution temperature. The temperature of solid solution is above the phase transition temperature and the strength of air-cooled is higher than that of furnace cooled room temperature. But the impact toughness and plasticity indexes do not change much. When the phase change temperature is above the solid solution temperature, the air-cooled temperature is slightly higher than that of the furnace, the impact toughness and the area shrinkage are much higher, the elongation has little change, but the yield strength decreases slightly. With the improvement of cooling rate, the high temperature strength showed a slight improvement trend, while the plasticity index did not change significantly. The selected solid solution temperature is 30 ~ 40℃ below the phase change point, and the rail system is designed for 2h air cooling +550℃ and 6h air cooling and heat treatment, which can ensure the optimal combination of plasticity and strength of the alloy.