| 摘要: |
| 双相钢点焊熔核中大量的相变马氏体,导致熔核脆性增加,其界面撕裂问题严重降低了焊点的力学性能,导致接头质量下降.采用传统的评价标准会产生焊点界面撕裂问题.针对双相钢焊点界面撕裂评价问题,建立了基于焊点宏观形貌与微观特征的双相钢焊点失效模式评价模型,获得了双相钢焊点界面撕裂的临界熔核直径评价标准,最后在1.4,1.8 mm厚DP600钢板上通过试验验证.结果表明,临界熔核直径评价标准克服了传统经验公式及现有评价标准考虑因素不全的缺点,成功地实现了双相钢焊点失效模式的准确评价. |
| 关键词: 双相钢 电阻点焊 界面撕裂 评价模型 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(50905111);上海汽车工业科技发展基金资助项目(0907) |
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| Evaluation on interfacial fracture mode of resistance spot weld dual-phase steels |
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YANG Haijun1, ZHANG Yansong1, LAI Xinmin1, ZHANG Xiaoyun2
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1.School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200240, China;2.Vehicle Manufacturing Engineering, Shanghai General Motors, Shanghai 201201, China
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| Abstract: |
| The interfacial fracture mode of dual phase steel(DP) weld greatly affects its mechanical performance and decreases its weld quality because much martensite in the nugget makes the welds brittle,but the traditional nugget diameter criteria is not suitable to estimate the quality of DP weld,and so this paper builds a mathematical mode based on macro-appearance and micro-mechanism to evaluate the different fracture modes of DP weld.Experimental results show that the model is effective on 1.4 mm and 1.8 mm DP600 welds and is also better than other evaluation criteria for their limited factors considered. |
| Key words: dual phase steel resistance spot welding interfacial fracture evaluation model |
