机械

Q235碳钢因其良好的焊接性能广泛应用于工业生产领域，其常用的MIG焊的焊接工艺参数在车间环境下受到焊接粉尘、油污等因素影响，焊接质量稳定性无法把控，本文在车间环境下对Q235碳钢MIG焊的焊接工艺进行研究，研究焊接电流的变化导致焊接线能量的变化对焊缝质量的影响，结合超声波无损检测、微观金相实验进行焊缝质量分析，最终确定最佳焊接工艺参数。研究发现：当焊接电流为86 A时，电弧相对不稳定，飞溅较多，成型质量差；随着电流增大到126 A时，电弧稳定，飞溅极少，成型质量良好；继续增大电流时，发现飞溅少，但焊缝成型质量差；结果表明，最佳焊接工艺参数为电流126 A、电压19 V、速度50 cm/min、气体流量1.7 L/min。

Q235 carbon steel has been widely used in many industrial fields because of its excellent weldability.The welding quality is easily affected by welding dust, oil pollution and other factors in welding workshops and thus cannot satisfy the demand of high quality of stability and reliability of product. The welding parameters affecting Q235 carbon steel welding quality are studied through ultrasonic inspection and micro-structure analysis. The study finds that when the welding current is 86 A, welding arc is unstable with more spatter and poor forming quality. As the current increases to 126 A, the welding arc becomes stable with minimal splashing and good forming quality. Increasing current from 126 A to 166 A, there is an obvious decrease in the spatter,but the quality of the weld formation is poor. The results show that the optimal welding parameters are current 126 A, voltage 19 V, speed 50 cm/min, and gas flow rate 1.7 L/min.