中文摘要：

采用真空扩散焊接的方法获得了Mg/CuNi/Al扩散焊接接头。采用万能试验机测试焊接接头剪切强度,通过SEM,EPMA,XRD对焊接接头的显微结构和物相组成进行了分析。结果表明,Mg/CuNi/Al扩散焊接接头剪切强度随焊接温度和保温时间的增加先增加后减小,焊接温度440℃,保温时间90 min时,接头剪切强度最大值达到22.4 MPa。焊接接头主要由Al3Mg2致密组织层、Al12Mg17针状组织层、Al12Mg17和α-Mg网状组织层组成,Cu、Ni富集于网状组织层中。Mg/CuNi/Al扩散焊接接头断口主要由Al3Mg2、Al12Mg17、AlCu3、Al2Cu和Al7Cu23Ni化合物组成,断裂方式以脆性断裂为主。

英文摘要：

The vacuum diffusion bonding was used to weld Mg to Al with a Cu Ni film interlayer.A universal testing machine was used to test the shear strength of the bonded joint.The microstructure of the bonded joints was studied by SEM and the phase composition was analyzed by XRD and EPMA.The results show that the shear strength increases firstly and then decreases with the bonding temperature and holding time increasing,and it exhibits a maximum value of 22.4 MPa at the bonding temperature of 440 ℃ and holding time of 90 min.The joints are composed of Al3Mg2 compact layer,Al12Mg17 acicular layer and Al12Mg17,α-Mg nets layer.The Al3Mg2,Al12Mg17,Al Cu3,Al2 Cu and Al7Cu23 Ni compound phases are formed on the fracture surface.The fracture way of the joints is brittle fracture.