2195铝锂合金重固溶-T8再时效的组织与力学性能

Microstructure and mechanical properties of re-solutionized and T8 re-aged 2195 Al-Li alloy

以5.2 mm厚2195-T8铝锂合金为基础,进行了重固溶及后续152℃的T8（预变形3%-6%）再时效处理,研究了其微观组织与拉伸性能。结果表明,重固溶处理未显著改变2195铝锂合金的晶粒组织,仍然保持为拉长的扁平状（带状）晶粒组织态。合金的主要时效强化相为T1相（Al2Cu Li）和θ＇相（Al2Cu）。T1相数量随预变形量增大而明显增加,而峰时效后θ＇相数量及尺寸随预变形量增加呈降低的趋势。合金中T1相分数随时效时间延长而增加并主要沿长度方向长大,而峰时效后θ＇相随时效时间延长逐渐减少。重固溶T8再时效处理未明显损害2195铝锂合金拉伸性能。

The microstructure and tensile properties of 2195-T8 Al-Li alloy after resolution treatment and T8 re-aging with 3%-6% predeformation at 152 ℃ were investigated.The results show that the resolution and T8 re-aging do not significantly damage the mechanical properties of the 2195-T8 Al-Li alloy.Meanwhile,the resolution treatment displays little influence on the grain structures,the grain after re-solution still maintains as elongated pancake-like appearance.The main strengthening precipitates are still T1（Al2 Cu Li） and θ＇（Al2Cu） phases.With the pre-deformation increasing,T1 precipitate fraction is evidently increased.During peak-aging and over-aging stages,there exists a tendency that θ＇ precipitate is decreased with pre-deformation increasing.With aging time extension,T1 precipitate fraction increases and the precipitates grow along length direction,but the fraction and size of θ＇ precipitates decrease with increasing aging time after peak-aging.