【摘要】 对变形镁合金AZ31B、AZ80A,砂铸镁合金AM60B、AZ91D及压铸镁合金AM50A激光焊接气孔倾向进行研究。研究表明:变形镁合金激光焊气孔倾向很小,在较宽的焊接工艺参数范围内均能得到无气孔的焊缝。砂铸镁合金AM60B及AZ91D激光焊时气孔对气体保护条件非常敏感,在侧吹气体保护角度及流量选择不合适时气孔率非常高,在优化的气保护条件下可得到气孔率较低的焊缝。而压铸镁合金AM50激光焊缝中气孔问题非常突出,调整工艺参数无法解决气孔问题,焊接过程中的加热及添加填充材料可以在一定程度上减少气孔。更多还原

【Abstract】 Tendency to pore formation of wrought magnesium alloys AZ31B, AZ80A,sand-cast magnesium alloys AM60B, AZ91D and die-cast magnesium alloys AM50A during laser welding are studied. The results show that wrought magnesium alloys are not prone to porosity and welds pore-free can be obtained in a wide range of welding parameters. Porosity in laser welds of sand-cast magnesium alloys is sensitive to gas shielding conditions and is very high under unsuitable gas shielding angle and flux. Low porosity welds can be obtained under optimized gas shielding conditions. Porosity is severe in die-cast AM50 laser welds and cannot be solved by optimizing welding parameters. Heating the work piece during welding and adding suitable filling materials can reduce porosity to some extent.更多还原