ABSTRACT Liquid metal embrittlement (LME) cracking can occur during resistance spot welding (RSW) in zinc-coated advanced high-strength steels (AHSS) for automotive production. In this study, a methodological variation of hold time is performed to investigate the process-related crack influence factors. A combination of numerical and experimental investigations confirms, that the extent of heat dissipation and re-heating of the sheet surface can be influenced and thus the degree of crack formation can be controlled in a targeted manner by the parameterisation of the hold time. The temperature and stress history of crack-free and crack-afflicted spot welds are analysed and a conclusion on the borders defining the LME active region is derived.

中文翻译：

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通过热输入相关的保持时间适应避免电阻点焊过程中液态金属脆化

摘要 用于汽车生产的镀锌高级高强度钢 (AHSS) 在电阻点焊 (RSW) 过程中会发生液态金属脆化 (LME) 裂纹。在这项研究中，通过保持时间的方法变化来研究与工艺相关的裂纹影响因素。数值和实验研究的结合证实，可以影响板表面的散热和再加热程度，因此可以通过保持时间的参数化以有针对性的方式控制裂纹形成的程度。分析了无裂纹和受裂纹影响的点焊的温度和应力历史，并得出了关于定义 LME 活动区边界的结论。