CuNiCoBe与CuCrZr合金电极的点焊性能比较及其失效分析

文中对比研究了CuNiCoBe合金与CuCrZr合金电极点焊镀锌钢板的性能，并利用超景深显微镜，光谱仪、XRD等分析测试手段研究了电极表面的剥落、端部塑性变形的程度及表面合金层的成分和物相等，分析了电极失效机理.结果表明，在相同的点焊工艺参数下，CuNiCoBe电极点焊寿命达到3 500点，为CuCrZr电极寿命1 500点的2.3倍.CuCrZr电极寿命低于CuNiCoBe电极的原因在于CuCrZr合金强度硬度低，易形成剥落孔洞、塑性变形大，电极端部尺寸增大明显.表面合金层的成分和产物和CuNiCoBe电极的不尽相同.

Comparison of spot welding performance and failure analysis of CuNiCoBe and CuCrZr electrodes

The spot-welding performances of galvanized steel were compared between and CuNiCoBe and CuCrZr electrodes. The peeling of electrode surface, the degree of plastic deformation of the end portion and the composition and phases of the surface layer were studied by means of super depth of field microscope, Spectrometer, XRD and so on,and the failure mechanism of electrodes were analyzed. The results had shown that at the same parameters, the life of CuNiCoBe electrode is 3 500 points, which is 1.3 times higher than that of CuCrZr electrode, which mainly caused by the low intensity and hardness of CuCrZr alloy, large possibility to form peeling holes, the large size of plastic deformation and apparent increase of size of electrode tip. The compositions and products of surface layer of CuCrZr electrode is not the same as that of CuNiCoBe electrode.