焊接残余应力对2219铝合金熔焊接头承载能力的影响  

Effect of welding residual stress on bearing capacity of fusion welded joint of 2219 aluminum alloy

作　　者：许欣欣[1,2] 梁晓光 杨瑞生 鄢东洋 周利 XU Xinxin;LIANG Xiaoguang;YANG Ruisheng;YAN Dongyang;ZHOU Li(State Key Laboratory of Advanced Welding and Connection,Harbin Institute of Technology,Harbin,150001,China;Shandong Key Laboratory of Special Welding Technology,Harbin Institute of Technology(Weihai),Weihai,264209,China;Beijing Institute of Aerospace Systems Engineering,Beijing,100076,China)

机构地区：[1]哈尔滨工业大学,先进焊接与连接国家重点实验室,哈尔滨150001 [2]哈尔滨工业大学(威海),山东省特种焊接技术重点实验室,威海264209 [3]北京宇航系统工程研究所,北京100076

出　　处：《焊接学报》2020年第10期17-22,I0002,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金委员会-中国航天科技集团公司航天先进制造技术研究联合基金,航天大型2219铝合金环件形性精准协调制造的科学基础(U1637601).

摘　　要：为了研究2219铝合金焊接残余应力对接头承载能力的具体影响以及作用机理,通过对比试验的方法测试了两种焊接接头的力学性能.建立焊接过程有限元模型,获得标准试样和大尺寸试样的残余应力分布,模拟结果表明标准试样制备过程中,焊接残余应力基本上完全释放.分别对含残余应力和不含残余应力试样进行力学拉伸和接头表征测试试验,试验结果表明焊接残余应力的存在不会对焊接接头的力学性能、断裂形式及断口特征产生明显影响.基于细观损伤的断裂力学理论,对焊接残余应力在接头拉伸过程中损伤产生及积累过程的影响机制进行详细分析及讨论.结果表明,焊接接头形成后的应力释放并不影响接头的承载能力,但是诸如随焊和焊后残余应力控制措施会导致接头产生额外塑性应变,可能会对接头承载能力产生影响.To study the specific effect of welding residual stress on the bearing capacity of 2219 aluminum alloy and its mechanism,the mechanical properties of the two welded joints were tested by comparative tests.The finite element model of welding process was established,and the residual stress distribution of standard specimen and largesized specimen was obtained.The simulation results showed that the welding residual stress was basically released during the preparation of standard samples.The mechanical tensile and joint characterization tests of specimens with and without residual stress were carried out respectively.The test results indicated that the existence of welding residual stress has no obvious effects on the mechanical properties,fracture forms and fracture characteristics of welded joints.Based on the theory of the fracture mechanics of mesoscopic damage,the mechanism of the damage and the accumulation of the residual stress in the joint was analyzed and discussed in detail.The results revealed that the released stress after the formation of the welded joint does not affect the bearing capacity of the joint,but the additional plastic strain which caused by the residual stress control measures during and after welding,which may have an impact on the bearing capacity of the joint.

关 键 词：残余应力 铝合金 力学性能 细观损伤 

分 类 号：TG457.14[金属学及工艺—焊接]