It combines the high thermal resistance of TA2 alloy with the thermal stability of TA1 alloy, and is suitable for long-term operation at 500~550℃.
The working time can reach 6000h below 500°C and 3000h at 550°C. Therefore, TC4 titanium alloy is an ideal thermally strong titanium alloy for engines. The alloy can be processed into titanium alloy forgings, titanium rods, die forgings and other forms of products.
Under the same solid solution temperature, the microstructure of air-cooled ones is finer than that of furnace-cooled ones. The solid solution temperature is above the phase transformation temperature, and the air-cooled one has higher strength than the furnace-cooled one at room temperature, but the impact toughness and plasticity index do not change much. The phase transformation temperature is above the solid solution temperature.
The strength of the air-cooled steel at the same solid solution temperature is slightly higher than that of the furnace-cooled room temperature. The impact toughness and section shrinkage are much higher. The elongation does not change much, but the yield strength is slightly reduced. The high-temperature strength shows a slight improvement trend with the increase of cooling rate, and the plasticity index does not change significantly. Selecting a solid solution temperature of 30~40°C below the phase transition point, 2 hours of air cooling + 550°C, and 6 hours of air cooling heat treatment system can ensure a good combination of alloy plasticity and strength.
