TB6钛合金等温锻后热处理工艺研究

Research on Heat Treatment Process of TB6 Titanium Alloy after Isothermal Forging

摘要:

采用等温锻压机对TB6钛合金方棒进行等温锻造,锻造完成后对锻件进行水淬和空冷2种不同方式的冷却,再对水淬的锻件进行时效处理,空冷的锻件进行固溶+时效处理。研究了等温锻后热处理工艺对TB6钛合金组织和力学性能的影响。结果表明,等温锻后水淬,α相尺寸较小,等温锻后空冷,α相尺寸较大;水淬后β基体上无感生α相,空冷后β基体上有感生α相形成;水淬+时效后析出的次生α相比空冷再经固溶+时效后析出的次生α相更加混乱。TB6钛合金经等温锻后水淬+时效处理,其强度和塑性与等温锻后空冷至室温再进行固溶+时效的水平相当,且平面应变断裂韧度更高。

Abstract:

TB6 titanium alloy square bar was isothermal forged by isothermal forging press in this research,the forged billets were cooled by different ways that water quenching and air cooling. The forged billets by water-quenched were aged and the forged billets by air-cooled were solid solution and aged after cooled. The effects of different heat treatments on the microstructure and mechanical properties of TB6 titanium alloy after isothermal forged were studied.The results show that alpha phase size of TB6 titanium alloy by water-quenched after isothermal forged is smaller than that by air-cooled after isothermal forged,there is no induced alpha phase in beta base of titanium alloy by waterquenched and there is induced alpha phase in beta base of titanium alloy by air-cooled. The precipitated secondary alpha phase of titanium alloy by water-quenched after aged is more chaotic than that by air-cooled after solid solution and aged. After isothermal forged,the strength and plasticity of TB6 titanium alloy by water-quenched after aged are similar to that by air cooled after solid solution and aged,but the fracture toughness of the former is higher than that of the latter.