5052-O铝合金电阻点焊裂纹产生机理及抑制

首先以5052-O铝合金(Al-Mg合金)为分析材料通过单脉冲电阻点焊工艺分析裂纹的产生及其机理,然后利用SORPAS软件模拟分析单脉冲、多脉冲工艺的裂纹倾向性,探讨采用平直端面电极+多脉冲工艺对接头热影响区液化裂纹的作用,并在优化电极+多脉冲工艺下结合模拟结果验证并分析抑制特定区域液化裂纹产生的机理.结果表明,多脉冲工艺相对于单脉冲而言,其裂纹危险分布系数有所降低,多脉冲工艺对裂纹产生的倾向性影响仍然较小,但是在优化电极+多脉冲工艺下电极端面的环状凹痕能够完全抑制裂纹的产生,并能够提升点焊接头的力学性能.

Mechanism and suppression of cracking in 5052-O aluminum alloy resistance spot weld

The initiation and formation mechanism of cracking was analyzed during single-impulse resistance spot welding of 5052-O aluminum alloy(Al-Mg alloys). SORPAS software was used to simulate and compare cracking risk factor with multi impulses to that with single impulse. The effect of cracking initiation in HAZ of welded joint with multi impulses process was also discussed. According to the simulation results, analysis and verification were performed regarding the mechanism of suppressing cracking in specific area of HAZ with optimized electrodes and multiple impulses. The results show that cracking risk factor with multi impulses seemed lower than that with single impulse, and the influence of multiple-pulse technology on cracking was small. However, the annular grooves generated by the optimized electrode and combined with multiple-pulse process can completely inhibit the generation of cracking, and enhance the mechanical properties of the spot welded joint.