摘要
对8 mm厚三层搭接结构的6061-T6铝合金进行搅拌摩擦点焊试验,并对对点焊接头的显微组织和力学性能进行研究。结果表明,接头微观形貌分为搅拌区、热力影响区、热影响区及母材区。当下压深度从7.0 mm增至8.2mm时,上层结合界面的完全结合区宽度从2.1 mm增至3.1 mm,下层结合界面的完全结合区宽度从2.0 mm增至3.0mm。接头硬度最低值在热影响区和热机影响区的交界处,搅拌区的平均硬度值随下压深度的增加而增大,最大值为73.4 HV。拉剪载荷与下压深度呈正相关的关系,随着下压深度从7.0 mm增至8.2 mm,拉剪载荷从8937 N增至16284N。在两个接合面处均发生断裂,断裂形式为剪切塞型混合断裂。
Friction stir spot welding tests for three-layer lap-joint of 6061-T6 aluminum alloy were carried out, and the microstructure characteristics and mechanical properties of the spot welded joints were investigated. The results show that the joint can be divided into stir zone(SZ), thermal mechanically affected zone(TMAZ), heat affected zone(HAZ) and base material(BM). When the penetration depth increases from 7.8 mm to 8.2 mm, the width of the complete bonding zone of the upper bonding interface increases from 2.1 mm to 3.1 mm, and the width of the complete bonding zone of the lower bonding interface increases from 2.0 mm to 3.0 mm. The minimum hardness of the joint is obtained at the junction of HAZ and TMAZ.The average hardness of the SZ increases with the increase of the penetration depth, and the maximum hardness is 73.4 HV.The tension-shear load is positively correlated with the penetration depth. With the penetration depth increasing from 7.0 mm to 8.2 mm, the tension-shear load increases from 8937 N to 16284 N. Fracture occurs at both bonding interfaces in the form of tensile-shear mixed fracture.
作者
陆轶
赵运强
董春林
王春桂
易耀勇
LU Yi;ZHAO Yunqiang;DONG Chunlin;WANG Chungui;YI Yaoyong(School of Materials Science and Engineering,Central South University,Changsha 410000,China;Guangdong Provincial Key Laboratory of Advanced Welding Technology,Guangdong Welding Institute(China-Ukraine E.O.Paton Institute ofWelding),Guangzhou 510651,China)
出处
《热加工工艺》
北大核心
2020年第5期12-15,24,共5页
Hot Working Technology
基金
广州对外科技合作计划项目(201807010068)
广东省科学院实施创新驱动发展能力建设专项资金项目(2018GD ASCX-0113)
国家重点研发计划项目(2018YFB1306400)
广东省重点领域研发计划项目(2019B090921003).
