铝-镁合金磁脉冲焊接界面形貌研究

Morphology Study of Al-Mg Alloy Magnetic Pulse Welding Interface

采用不同的焊接工艺参数对1060铝合金与AZ31镁合金进行磁脉冲焊接试验。结合铝-铝界面形貌,对比探讨磁脉冲铝-镁异种金属焊接接头界面波特征。通过SEM/EDS、纳米压痕试验,着重研究界面'熔化区'的产生机理、分布特点以及此区域的硬度变化。试验结果表明:界面呈不规则的波状结合方式,嵌入镁层的界面波远大于铝层;在'熔化区'会生成脆硬的第二相,此相分布在Al基一侧。通过调整适当的焊接工艺参数可避免此'熔化区'产生。

Magnetic pulse welding between 1060 aluminum alloy and AZ31 magnesium alloy was conducted with different welding process parameters. Compared with the interface morphology of aluminum-aluminum joint, the characteristics of interface waves in Al-Mg dissimilar metal welding joint were discussed. With the help of SEM/EDS and the NANO INDENTER test analysis, the formation mechanism and the distribution of ＂melt zone＂, and the change of hardness in this zone were investigated. The results show that the interface is of irregular wavy binding mode, and the interface wave embedded in the magnesium layer is much larger than that embedded in the aluminum wave; the ＂melt zone＂ will generate a rigid second phase, which is distributed in the Al-based side. Trough adjusting the appropriate welding parameters, it is obviously useful to avoid the formation of ＂melt zone＂.