电阻焊钼电极开裂失效问题的研究

Research on Problems of Mo Electrodes Crack During Resistance Spot Welding

电触头在点焊过程中所用的钼电极材料容易开裂而失效。分析知焊接热应力和钼电极材料自身性能是引起开裂的两大主因。运用Ansys模拟了改进焊接工艺前后电极的热应力,模拟显示改进工艺并未能显著降低热应力,说明通过改进工艺来延长电极寿命的方法不可取。对已失效钼电极材料性能进行研究,发现材料脆性是钼电极快速失效的主要原因。根据学者们已有的研究成果可知,在保证钼电极使用性的前提下进行合金化,才是提高钼电极抗裂性能的有效方法。

Mo electrode is easy cracked in the process of spot welding with electrical contacts. Research shows that the Mo electrode cracking is caused by welding thermal stress and the material＇s properties. Ansys was used to simulate the electrode thermal stress before and after the improvement of welding process. The simulations show that the improved process does not significantly reduce the thermal stress. So,it does not work in extending the life of electrode by improving the process. Meanwhile,by exploring the properties of Mo electrode materials,it was found that material brittleness is the main reason causing the rapidly failure of Mo electrode. According to the current research achievements,alloying in the premises of guaranteeing the usability of Mo electrode is an effective way to improve the anti-crack performance of Mo electrode.