Experimental study on gas metal arc welding and laser hybrid welding of WYS700 steel

Gas metal arc welding, laser welding, and laser-metal active gas welding(MAG) hybrid welding methods were applied to WYS700 steel.Different welding procedures were performed and different welding technologies were compared.Macro metallographs of the welded joints were obtained, and the mechanical properties(such as tensile strength, bending property, and hardness) of the joints formed using the different welding technologies were determined.The results revealed that the joint of the WYS700 steel could be formed well through gas metal arc welding, laser welding, and laser-MAG hybrid welding.Furthermore, the softening of the welding heat affected zone can be effectively reduced to obtain good strength and plasticity by using a suitable welding procedure.Laser-MAG hybrid welding allows the realization of high efficiency and deep penetration for the welding of thick plates with specifications above 3 mm.

保护气流量对不锈钢激光-MAG复合焊接头组织和性能的影响

对8 mm厚SUS301L-MT不锈钢进行激光-MAG复合焊接,研究不同保护气流量对焊缝成形、显微组织和力学性能的影响。试验结果表明:当其他焊接参数一定时,在该试验条件下保护气流量对焊缝成形影响较小,焊缝区域组织相似,主要为柱状奥氏体树枝晶+少量的δ铁素体。接头显微硬度和冲击韧性随保护气流量的变化不明显。接头的抗拉强度随保护气流量的增加而提高,当保护气流量为40 L/min时,接头抗拉强度最高为765 MPa,达到母材抗拉强度的86.5%。分析拉伸断口发现,不同保护气流量断口微观形貌相似,断口中分布着大量韧窝,表现为韧性断裂。