摘要
研究800 MPa级冷轧双相钢电阻点焊工艺,分析点焊电流对接头形貌、性能以及组织缺陷的影响规律,讨论回火脉冲对提升接头性能的影响。结果表明:点焊电流对高强钢DP800接头形貌、性能及缺陷等均有较大影响;当点焊电流达到10 k A时,剪切试验为纽扣型断裂模式,最大剪切力达到34.28 k N;点焊脉冲后附加回火脉冲可以提高点焊接头性能。
Spot welding of 800 MPa grade dual-phase steel was investigated.The effect of welding current on the welding morphology,mechanical properties,metallographic microstructure and welding defects of spot welded joints were investigated.The results showed that the welding current had remarkable effects on the welding morphology,mechanical properties.When the welding current was 10 k A,the fracture mode of steel joins was button pullout fracture,the maximum shear stress was 34.28 k N;temper pulse could effectively improve the performance of spot welding joints.
引文
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