(中南大学 材料科学与工程学院，长沙 410083)
摘 要: 研究不同热处理工艺对2A97铝锂合金拉伸性能和腐蚀性能的影响。结果表明：合金经热处理工艺C(5%预变形+100 ℃, 1.5 h+5%中间变形+160 ℃, t)处理后，获得较好的强度与塑性的配比，在峰时效状态下，合金抗拉强度和伸长率分别为597 MPa和7.4%。同时，合金耐晶间腐蚀性能优异，平均晶间腐蚀深度为22 μm。在分步变形和双级时效的综合作用下，合金在峰时效晶内获得大量弥散细小的T1相和少量的S′相，晶界处析出相稀少，无沉淀析出带不明显，使2A97合金获得高强度的同时，改善塑性和耐晶间腐蚀性能。
关键字: 2A97铝锂合金；微观组织；晶间腐蚀；双级时效
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The effects of various heat treatment processes on tensile and corrosion properties of 2A97 Al-Li alloy were investigated. The results show that, undertaken with heat treatment process C (pre-deformation 5%+100 ℃, 1.5 h+mid-deformation 5%+160 ℃, t), the alloy obtains preferable combination of strength and ductility. At the peak-aged condition of heat treatment process C, the tensile strength and elongation of 2A97 Al-Li alloy are 597 MPa and 7.4%, respectively. Meanwhile, the intergrannular corrosion resistant is excellent, and the average intergranular corrosion depth is 22 μm. Under the comprehensive function of multi-step deformation and two-step aging, the large quantities of T1 precipitate dispersedly in grain with some S′ phase, few second phases precipitate in grain boundary, and the precipitation free zone is not obviously near grain boundary, which respond to the favorable tensile properties and corrosion properties of 2A97 Al-Li alloy at peak-aged.
Key words: 2A97 Al-Li alloy; microstructure; intergrannular corrosion; two-step aging
