(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083；
2. 中南大學(xué) 機電工程學(xué)院，長沙 410083；
3. 上海飛機設(shè)計研究院，上海 200232)
摘 要: 利用金相顯微鏡、顯微硬度測試、拉伸性能測試、掃描電鏡、透射電鏡等手段對2060-T8合金攪拌摩擦焊(FSW)接頭的微觀組織和力學(xué)性能進行研究。結(jié)果表明：焊接頭的抗拉強度為441 MPa，屈服強度為320 MPa，伸長率為6.9%，但焊接強度系數(shù)達到82.9%；經(jīng)過攪拌摩擦焊，母材的織構(gòu)類型以及強度發(fā)生了變化，由黃銅織構(gòu)變?yōu)楦咚箍棙?gòu)且強度變?nèi)酰粺嵊绊憛^(qū)T1相(Al2CuLi)部分發(fā)生了溶解，析出了δ′相(Al3Li)，熱機影響區(qū)內(nèi)T1相大部分溶解，S′相(Al2CuMg)發(fā)生了粗化，焊核區(qū)析出相全部溶解。
關(guān)鍵字: 鋁鋰合金；攪拌摩擦焊；微觀組織；力學(xué)性能
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. Shanghai Aircraft and Research Institute, Shanghai 200232, China）
Abstract:The 2060-T8 FSW joint was studied by means of metallographic microscope, microhardness test, tensile test, SEM and TEM on the microstructure and mechanical properties. The results show that the tensile strength is 441 MPa, the yield strength is 320 MPa and the elongation is 6.9%. But the joint strength coefficient is 82.9%. The texture type and intensity of base material change after FSW, and the texture type changes from Bass texture to Gauss texture and the intensity decreases. T1 precipitates partly dissolve and δ′ precipitates are found in heat affected zone (HAZ). More T1 precipitates dissolve and S′ precipitates are coarsen in thermo mechanically affected zone (TMAZ). The precipitates absolutely dissolve in nugget zone (NZ).
Key words: Al-Li alloys; friction stir weld; microstructure; mechanical property
