热处理工艺对Ti60合金持久性能的影响

将α+β两相区变形的Ti60合金锻件分别在950、995、1015℃进行固溶处理,研究了固溶温度和冷却方式对Ti60合金微观组织及持久性能的影响。结果表明:Ti60合金的显微组织和持久性能受固溶温度和冷却方式的双重影响。950℃固溶处理,冷却方式对合金组织的影响较小,空冷试样的持久性能略低于油冷试样。995℃和1015℃固溶处理,随温度的升高组织中的初生α相含量降低,空冷组织中的初生α相尺寸略大于油冷组织;在实验温度范围内,Ti60合金的持久性能随固溶温度的升高而升高,且在相同固溶温度下,空冷试样在600℃、340 MPa下的持久寿命明显高于油冷试样。次生α相的含量和α板条/α集束的尺寸是影响Ti60合金持久寿命的重要因素,合金的持久寿命与二者成正相关。

Effect of Heat Treatment on Rupture Property of Ti60 Alloy

The effects of solution temperature and cooling method on the microstructure and rupture property of Ti60 alloy were studied. The Ti60 alloy forging was deformed in the α + β two-phase field. And the small samples cutted from the rolling ring were heat-treated at 950 ℃,995 ℃ and 1 015 ℃ . The results show that the microstructure and rupture property are affected by both the solution treatment and the cooling method. After 950 ℃ solid solution treatment,the cooling method has little effect on the microstructure,and the rupture property of air-cooled sample is slightly lower than that of oil-cooled sample. At 995 ℃ and 1 015 ℃,the content of primary α phase decreases with the increase of solution temperature,and the size of primary α phase in the air-cooled sample is slightly larger than that in the oil-cooled sample. In this temperature range,the rupture property of Ti60 alloy increases with the increase of solution temperature,and the rupture property of air-cooled sample at 600 ℃ and 340 MPa is significantly higher than that of oil-cooled sample. The content of secondary α phase and the size of α laths/colony are important factors influencing the rupture life of Ti60 alloy and they are positively related.