深冷处理的铝合金点焊电极寿命研究

为了提高铝合金点焊电极寿命,提出了点焊电极的深冷处理方法。采用不同深冷处理工艺参数加工了点焊电极,用这些电极进行了铝合金点焊电极寿命试验,比较了深冷处理电极与未深冷处理电极寿命,观测、比较了深冷处理前后点焊电极端面、焊点表面的宏观形貌,观察了深冷处理电极与未深冷处理电极微观组织,测试了深冷处理电极与未深冷处理电极物理性能。试验结果表明:深冷处理改变了电极微观组织,改善了电极导电、导热性能,提高了点焊电极寿命,使电极寿命由原来的620点提高到2 145点。

STUDY ON DEEP CRYOGENIC TREATMENT ELECTRODE LIFE FOR SPOT WELDING ALUMINUM ALLOY

To improve electrode life of resistance spot welding of aluminum alloy LF2, the deep cryogenic treatment technology of electrodes is put forward. Electrodes are treated by deep cryogenic treatment with different deep cryogenic treatment parameters. Deep cryogenic treatment electrodes life experiment is carried out and the experimenal results are compared with the non-deep cryogenic treatment electrodes life experiment ones. The properties of the deep cryogenic treatment electrodes and the non-deep cryogenic treatment electrodes are tested. The SEM area scanning and the SEM back scattering of electrodes are carried out. The grain degree of deep cryogenic treatment electrodes and the non-deep cryogenic treatment electrodes are tested by X-ray diffraction. The reason of deep cryogenic treatment improving electrode life for resistance spot welding of aluminum alloy is studied. The experimental results show that deep cryogenic treatment makes Cr, Zr in deep cryogenic treatment electrodes emanate dispersedly and makes the grain of deep cryogenic treatment electrodes smaller than non-cryogenic treatment ones, so that the electrical conductivity and the thermal conductivity of deep cryogenic treatment electrodes are improved very much, which make electrode life for spot welding aluminum alloy improve from 620 to 2 145 .