摘要
研究了２０９１Ａｌ－Ｌｉ合金ＴＩＧ焊焊接接头焊态及不同热处理状态下的显微组织和拉伸性能。结果表明：在焊态焊缝区已存在少量细小的沉淀强化相δ′相，但由于其体积分数小，沉淀强化作用弱，此时固溶强化为主要强化机制，接头强度较低，接头强度系数为６４％。焊后经人工时效处理，由于有大量的沉淀强化相δ′和ｓ′相析出，沉淀强化作用强，接头强度有明显提高，接头强度系数可达８９％。焊后经固溶处理加人工时效，沉淀强化相分布均匀，尺寸适中，接头强度大大提高，接头强度系数高达９８％。
The microstructure and tensile properties of TIG welded joints of Al-Li alloy were investigated both in as welded and different postweld heat treatment conditions. The results show that solid solotion strengthening played an important role in the as welded condition, though the precipitation strengthening δ′ phase formed already in the as welded weld metal, but its effect was not apparent due to the lower volume fraction of δ′ phase. So the strength ration of the welded joint/base metal (φ) was 64%. After artificially aging heat treatment, the precipitation strengthening effect increaced much due to the formation of more δ′ phase and s′ phase. Its φ value was increased up to 89%. The highest stength of the welded joints was obtained after solid solution and then artificially aged heat treatment. Due to the proper size of recipitation strengthening phases and their well distribution, theφ value was increased up to 98%.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
1998年第3期154-158,共5页
Transactions of The China Welding Institution
