(中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 研究不同熱處理工藝對(duì)2A97鋁鋰合金拉伸性能和腐蝕性能的影響。結(jié)果表明：合金經(jīng)熱處理工藝C(5%預(yù)變形+100 ℃, 1.5 h+5%中間變形+160 ℃, t)處理后，獲得較好的強(qiáng)度與塑性的配比，在峰時(shí)效狀態(tài)下，合金抗拉強(qiáng)度和伸長(zhǎng)率分別為597 MPa和7.4%。同時(shí)，合金耐晶間腐蝕性能優(yōu)異，平均晶間腐蝕深度為22 μm。在分步變形和雙級(jí)時(shí)效的綜合作用下，合金在峰時(shí)效晶內(nèi)獲得大量彌散細(xì)小的T1相和少量的S′相，晶界處析出相稀少，無(wú)沉淀析出帶不明顯，使2A97合金獲得高強(qiáng)度的同時(shí)，改善塑性和耐晶間腐蝕性能。
關(guān)鍵字: 2A97鋁鋰合金；微觀組織；晶間腐蝕；雙級(jí)時(shí)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
