论文部分内容阅读
研究不同焊接电极压力对酸洗和未酸洗的2A21铝合金试样的拉剪强度和点焊接头微观组织的影响。结果表明,经过酸洗的试样焊后无表面裂纹,而未酸洗的试样焊后焊点质量较差,存在表面裂纹;焊接压力0.24MPa、焊接时间110ms、焊接电流18kA时,焊点成形状况最佳,且熔核直径随电极压力的增大而减小,此时,柱状晶及大量的等轴细晶弥散分布,拉剪屈服强度最大。
The effects of different welding electrode pressure on the tensile strength and the microstructure of spot welded joints of 2A21 aluminum alloy samples, which were pickled and unwashed, were studied. The results show that there is no surface crack in the pickled sample, but the quality of the welded spot of the pickled sample is poor with the surface crack. The welding pressure is 0.24MPa, the welding time is 110ms and the welding current is 18kA. Forming the best shape, and the nugget diameter decreases with the increase of electrode pressure, this time, the columnar crystals and a large number of equiaxed fine grain dispersed distribution, tensile shear yield strength maximum.