Aluminium-copper hybrid parts, as a substitution to copper parts, result in weight and cost reduction, and are relevant in applications related to the electronic, heating and cooling sector. However, aluminium to copp...Aluminium-copper hybrid parts, as a substitution to copper parts, result in weight and cost reduction, and are relevant in applications related to the electronic, heating and cooling sector. However, aluminium to copper joined by thermal welding processes presents challenges in terms of achieving good joint quality. This is attributed to their dissimilar mechanical and thermal properties which result in large stress gradients during heating. This study investigated joining of aluminium to copper sheets by electromagnetic pulse welding, which is a solid-state process that uses electromagnetic forces for joining of dissimilar materials. Hybrid sheet welds were obtained for all parameters conditions, selected according to a Taguchi L18 design. The structural and mechanical characteristics were examined and related to the welding parameters by means of a Pareto analysis and response graphs. The welded zone started with a wavy interface with interfacial layers and defects and evolved to a flat interface without interfacial layers. The maximum transferable force depended on the minimum specimen thickness and the strength of the hybrid sheet weld. In case of aluminium sheet thickness reduction, the maximum transferable force was linearly correlated with the aluminium sheet thickness. High quality joints were obtained for no aluminium sheet thickness reduction and for a sheet weld strength which was at least as high as that of the base material. The most effective way to increase the transferable force was to lower the initial gap and to increase the free length, which resulted in no aluminium sheet thickness reduction. Alternatively, the use of a rounded spacer decreased the effect of the aluminium sheet thickness on the transferable force. An increase in weld width was achieved for an increase in capacitor charging energy and gap, whereas an increase in weld length was obtained for a decrease in gap. An increase in weld width did not necessarily result in an increase in the transferable force. In the regarded cases, a hybrid sheet with narrow weld width could therefore have higher quality.展开更多
通过CMT(Cold Metal Transfer)冷金属过渡焊接的工艺对镁(AZ31B)-铝(6061)异种金属焊接性进行了研究,试验中选用AZ61,4043焊丝、采用热镀锌钢板HDG60作为过渡金属,分别用于镁-钢、铝-钢侧焊接,选取合适的焊接工艺参数,使其间接实现了镁...通过CMT(Cold Metal Transfer)冷金属过渡焊接的工艺对镁(AZ31B)-铝(6061)异种金属焊接性进行了研究,试验中选用AZ61,4043焊丝、采用热镀锌钢板HDG60作为过渡金属,分别用于镁-钢、铝-钢侧焊接,选取合适的焊接工艺参数,使其间接实现了镁-铝异种金属连接的目的。研究得出:使用这种方法可以形成镁-钢熔钎焊焊接接头,铝-钢熔钎焊焊接接头组成的复合接头;同时冷金属过渡焊接可以通过保持较低焊接热输入从而降低界面反应层的厚度;而且镀锌钢板中间过渡层的使用也避免了镁-铝直接焊接时形成的脆性金属间化合物,如Al_3Mg_2,Mg_(17)Al_(12)等。采用该方法连接的镁-铝异种金属焊接接头的抗拉强度超过180 MPa,并且有较好的断后伸长率,相比铝镁异种金属CMT直接焊接,性能得到很大的改善,因此使用镀锌钢板中间过渡层的使用实现铝镁异种金属之间的连接是一种行之有效的方法。展开更多
文摘Aluminium-copper hybrid parts, as a substitution to copper parts, result in weight and cost reduction, and are relevant in applications related to the electronic, heating and cooling sector. However, aluminium to copper joined by thermal welding processes presents challenges in terms of achieving good joint quality. This is attributed to their dissimilar mechanical and thermal properties which result in large stress gradients during heating. This study investigated joining of aluminium to copper sheets by electromagnetic pulse welding, which is a solid-state process that uses electromagnetic forces for joining of dissimilar materials. Hybrid sheet welds were obtained for all parameters conditions, selected according to a Taguchi L18 design. The structural and mechanical characteristics were examined and related to the welding parameters by means of a Pareto analysis and response graphs. The welded zone started with a wavy interface with interfacial layers and defects and evolved to a flat interface without interfacial layers. The maximum transferable force depended on the minimum specimen thickness and the strength of the hybrid sheet weld. In case of aluminium sheet thickness reduction, the maximum transferable force was linearly correlated with the aluminium sheet thickness. High quality joints were obtained for no aluminium sheet thickness reduction and for a sheet weld strength which was at least as high as that of the base material. The most effective way to increase the transferable force was to lower the initial gap and to increase the free length, which resulted in no aluminium sheet thickness reduction. Alternatively, the use of a rounded spacer decreased the effect of the aluminium sheet thickness on the transferable force. An increase in weld width was achieved for an increase in capacitor charging energy and gap, whereas an increase in weld length was obtained for a decrease in gap. An increase in weld width did not necessarily result in an increase in the transferable force. In the regarded cases, a hybrid sheet with narrow weld width could therefore have higher quality.
基金Project (E201128) supported by the Natural Science Foundation of Heilongjiang Province, ChinaProject (20112303120001) supported by Specialized Research Fund for the Doctoral Program of Higher Education, ChinaProject (12520140) supported by the Foundation of Heilongjiang Educational Committee, China
文摘通过CMT(Cold Metal Transfer)冷金属过渡焊接的工艺对镁(AZ31B)-铝(6061)异种金属焊接性进行了研究,试验中选用AZ61,4043焊丝、采用热镀锌钢板HDG60作为过渡金属,分别用于镁-钢、铝-钢侧焊接,选取合适的焊接工艺参数,使其间接实现了镁-铝异种金属连接的目的。研究得出:使用这种方法可以形成镁-钢熔钎焊焊接接头,铝-钢熔钎焊焊接接头组成的复合接头;同时冷金属过渡焊接可以通过保持较低焊接热输入从而降低界面反应层的厚度;而且镀锌钢板中间过渡层的使用也避免了镁-铝直接焊接时形成的脆性金属间化合物,如Al_3Mg_2,Mg_(17)Al_(12)等。采用该方法连接的镁-铝异种金属焊接接头的抗拉强度超过180 MPa,并且有较好的断后伸长率,相比铝镁异种金属CMT直接焊接,性能得到很大的改善,因此使用镀锌钢板中间过渡层的使用实现铝镁异种金属之间的连接是一种行之有效的方法。
