奥氏体不锈钢薄板激光焊表面张力驱动熔池形成的数值模拟分析  

Numerical Simulation of Weld Pool Formation Driven by Surface Tension in Laser Welding of Austenitic Stainless Steel Sheet

作　　者：周世杰[1,2] 段瑞 苏哲[1,2] 李雪峥 ZHOU Shijie;DUAN Rui;SU Zhe;LI Xuezheng(Tianjin Institute of Special Equipment Inspection&Technical Research,Tianjin 300060,China;Key Laboratory of Digital Twin Generic Technology in Special Equipment for State Market Regulation,Tianjin 300060,China)

机构地区：[1]天津市特种设备监督检验技术研究院,天津300060 [2]国家市场监管重点实验室(特种设备数字孪生共性技术),天津300060

出　　处：《电焊机》2024年第6期87-93,共7页Electric Welding Machine

摘　　要：为探究奥氏体不锈钢薄板激光焊接过程中表面张力对熔池形状、熔池流速、熔池静压的影响,以期优化焊接工艺并提高焊接质量。基于数值模拟分析方法,建立了移动旋转高斯曲面体热源模型,通过改变Marangoni对流系数来模拟不同表面张力条件,分析其对熔池形成过程、熔池形状、流速及熔池内静压力的影响。模拟结果表明,表面张力是影响熔池形态和内部静压力的关键因素,表面张力指向熔池内部,驱动熔池向中心汇聚,从而促进熔池的形成;表面张力的大小与熔池峰值温度、熔深、深宽比呈负相关,与峰值流速、熔宽、熔池内部静压力呈正相关;铜衬底的加入显著增大了过冷度,加速了熔池的冷却,有助于避开奥氏体不锈钢的敏化温度区间。To explore the impact of surface tension on the shape,flow rate,and static pressure of the molten pool during the laser welding process of austenitic stainless steel sheets,with the aim of optimizing welding processes and enhancing welding quality.Based on numerical simulation analysis methods,a moving rotating Gaussian curved body heat source model was established.By altering the Marangoni convection coefficient to simulate different surface tension conditions,the effects on the formation process,shape,flow rate,and static pressure within the molten pool were analyzed.The simulation results indicate that surface tension is a key factor affecting the morphology and internal static pressure of the molten pool.Surface tension,pointing towards the interior of the molten pool,drives the pool to converge towards the center,thereby promoting the formation of the molten pool.The magnitude of surface tension is negatively correlated with the peak temperature,penetration depth,and aspect ratio of the molten pool,and positively correlated with the peak flow rate,penetration width,and static pressure within the molten pool.The addition of a copper substrate significantly increases the undercooling,accelerating the cooling of the molten pool and helping to avoid the sensitization temperature range of austenitic stainless steel.

关 键 词：奥氏体不锈钢 激光焊 表面张力 熔池流动 熔池形状 

分 类 号：TG456.7[金属学及工艺—焊接]