焊接时间对低碳钢点焊接头组织和性能的影响

Effect of Welding Time on Structure and Properties of Low Carbon Steel Spot Welding Joints

保持电极压力和焊接电流不变,研究了焊接时间变化对低碳钢点焊接头组织和抗剪切性能的影响。结果表明:低碳钢点焊接头的熔核区组织主要为板条马氏体,热影响区组织为板条马氏体和铁素体。随着焊接时间的增加,熔核区的马氏体板条群尺寸增大,硬度有所下降,受熔核尺寸和压痕深度的影响,抗剪切力先增大后减小。

The effect of welding time change on the microstructure and shear properties of spot welded joints of low carbon steel was studied by keeping the electrode pressure and welding current constant. The results show that the structure of the nugget zone of low carbon steel spot welding joint is mainly lath martensite, and the structure of the heat affected zone is lath martensite and ferrite. With the welding time increasing, the size of the martensite lath group in the nugget area increases,the hardness decreases, and the shear resistance increases first and then decreases due to the influence of the nugget size and the depth of indentation.