光束焦点位置对双相不锈钢光纤激光#br# 焊接焊缝成形和组织的影响

通过焊接热模拟方法和现代材料组织分析技术，研究了光束焦点位置对于双相不锈钢2205光纤激光焊接焊缝成形和组织的影响.结果表明，激光焦点位置影响了接头温度场分布，随着激光焦点下移进入工件内，焊缝上部逐渐收窄变短，焊缝内气孔数量显著下降，热影响区尺寸无显著改变.此外，光束焦点位置对双相不锈钢焊缝组织具有影响.正离焦时，焊缝中部的奥氏体含量最高；当离焦量为0 mm时，焊缝金属上部、中部和下部的奥氏体分布最为均匀.

Effects of Beam Focus Position on the Duplex Stainless Steel#br# Fiber Laser Welded Joint Shape and Microstructure

Effects of beam focus position was studied on the 2205 duplex stainless steel fiber laser welded joint shape and microstructure. By welding heat simulation and joint miscorstucture analysis. It was showed that the temperature field of the joint varied as the changes of laser beam foucs position changed. Besides, when laser beam focus position was moved downward, the width of weld and the number of pore in weld were decreased, but heat affect zone was the invariant. In addition, the microstructure of 2205 duplex stainless steel was effected by laser beam foucs position. When laser beam focus position was positive, the Austenite content was the highest than other conditions. When laser beam was focused on surface, the Austenitic distribution in the weld became even.