Ultrasonic Spot Welding of Lightweight Alloys
The structural applications of lightweight alloys in the automotive and aerospace industries inevitably involve welding and joining of challenging dissimilar Mg-to-Al and Mg-to-steel while guaranteeing safety and structural integrity.Sound dissimilar lap joints were achieved via ultrasonic spot welding (USW) – an environment-friendly solid-state joining technique.The addition of Sn interlayer during USW effectively blocked the formation of brittle Al12Mg17 intermetallic compound in the Mg-to-Al dissimilar joints without interlayer,and led to the presence of a distinctive composite-like Sn and Mg2Sn eutectic structure in both Mg-to-Al and Mg-to-HSLA (high strength low alloy) steel joints.The lap shear strength of both types of dissimilar joints with a Sn interlayer was significantly higher than that of the corresponding dissimilar joints without interlayer.Failure during the tensile lap shear tests occurred mainly in the mode of cohesive failure in the Mg-to-Al dissimilar joints and in the mode of partial nugget pull-out in the Mg-to-HSLA steel dissimilar joints.In particular,the addition of Sn interlayer resulted in energy saving since the welding energy required to achieve the maximum strength decreased from 1250 J to 1000 J in the Mg-to-Al joints and from 1750 J to 1500 J in the Mg-to-HSLA steel joints.
Magnesium alloy Ultrasonic spot welding Intermetallic compounds Tin interlayer
V.K. Patel S.D. Bhole D.L. Chen
Department of Mechanical and Industrial Engineering,Ryerson University,M5B 2K3,Canada
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）