【摘要】 采用CO2激光对轧制态细晶粒ZK60镁合金板材进行了焊接。研究了焊接工艺参数对接头显微组织和力学性能的影响规律,并分析了细晶粒镁合金板材的焊接特点。结果表明,在合适的工艺条件下,可以获得成形性能良好,无半熔化区(PMZ)液化裂纹的焊接接头;其抗拉强度和伸长率达到了295MPa,11.7%,分别为母材的91%和62%;熔池(FZ)边界处的胞状晶和柱状晶区范围较窄,约为20μm,熔池区由细小的等轴晶构成;从熔池区(FZ)到热影响区(HAZ)再到母材(BM)晶粒尺寸差别在3μm以下,焊接接头呈韧性断裂模式。更多还原

【Abstract】 Fine-grained ZK60 magnesium alloy sheets were joined by CO2 laser beam welding.The effects of welding parameters on microstructures and mechanical properties of the joints were investigated,and the welding characteristics of fine-grained magnesium alloy were analyzed.The results show that a favorable weld joint without distortion and liquation cracking in PMZ can be observed under the suitable processing parameters.The ultimate tensile strength(UTS)and elongation reach up to 295MPa and 11.7%,which are 91% and 62% of the base metal,respectively.The width of cellular and columnar grains at the fusion boundary is about 20μm,and the fusion zone is characterized by equiaxed grains.The difference in the grain size from the fusion center to the HAZ and to BM is lower than 3μm.The fracture mechanism is characterized by ductility mode.更多还原