2519铝合金热压缩变形过程的动态与静态软化行为

Dynamic and Static Softening Behaviors of 2519 Aluminum Alloy during Multi-stage Hot Compression Deformation

在Gleeble-1500热力模拟机上,采用双道次间隙式等温热压缩试验,对2519铝合金多道次热压缩变形过程中动态与静态软化特性进行了研究,变形温度为300～500 ℃,应变速率为0.05～5.00 s-1,两道次间隙时间在30～120 s内变化,每道次应变控制在0.4.研究结果表明:在500 ℃时,2519铝合金流动应力由于结构软化而存在相当强的动态软化和奇异的静态软化,导致第2道次的起始流动应力比前一道次的起始流动应力低;在热压缩变形道次间保温停歇后,流变应力出现明显的软化现象,保温停歇时间越长,合金软化率越高;变形及停歇保持温度越高,合金软化越严重.

The dynamic and static softening behaviors of 2519 aluminum alloy in multi-stage hot compression were studied. The isothermal interrupted hot compression tests were performed in the temperature range of 300-500°C and strain rate range of 0.05-5.00 s-1 on Gleeble-1500 thermal-mechanical simulator. The interrupted deformations were conducted with delay time varying between 30-120 s after achieving a strain of approximately 0.4 in the first stage. The results show that the considerable dynamic softening and exceptional softening associated with a structure softening exist in 2519 aluminum alloy deformation at 500°C, the initial flow stress value at the second deformation is lower than that at the first deformation, and the flow stress drops obviously. The static softening increases with the increase of deformation temperature, holding temperature and delay time.