【摘要】 以CO2激光为热源,镀锌钢板为母材,CuSi3焊丝为钎料,进行了双光束激光自动填丝钎焊工艺试验。通过对比单、双光束钎焊特点及改变双光束钎焊工艺参数,分析了双光束激光功率、离焦方式、双束激光能量配比、焦点间距等对接头质量的影响。结果表明,双光束钎焊对激光功率的变化具有更大的适应性;当采用负离焦并行双光束、2 mm焦点距离的串行双光束且前束激光功率大于后束激光时,可以获得更好的钎缝质量,钎焊过程更具灵活性、适应性。在此基础上,借助金相显微镜、SEM和EDX能谱分析,对接头组织及界面元素分布规律进行了分析。结果表明,双光束钎缝附近母材晶粒更细小,粗晶区更窄;在界面处有Fe-Si金属间化合物生成。更多还原

【Abstract】 The experiments of dual laser beam brazing of galvanized steel sheets with automatic wire feeding were carried out,in which CuSi3 was used as filler metal.The influence of laser power,defocusing type,dual laser beam energy ratio and distance between the spots on joint quality were analyzed. The experimental results indicate that better process adaptability is found in dual beam brazing with the variation of laser power,and more excellent joint quality is obtained when negative defocusing account of parallel beam brazing is used,or the distance between the spots of tandem dual laser beams is 2 mm and the first laser beam power is larger than the second one.Moreover,optical microscope,SEM and EDX were used to analyze the microstructures and elements distribution at the interface.The results show that the base metal grain size of the dual beam brazed joint is smaller than the single beam brazed joint’s,and the coarse grain zone is narrower.At the same time,there are Fe-Si intermetallics at the interface of dual beam brazed joint.更多还原