摘要
为了准确的模拟出激光深熔焊接中匙孔变化的动态过程,根据匙孔内激光的能量吸收机制,采用射线跟踪法产生热源,建立了激光深熔焊接过程中气、液、固三相统一的数学模型,并采用了VOF方法追踪自由液面,模型中考虑了表面张力、热浮力和反冲压力的作用,通过数值计算得到了匙孔变化的动态过程与相应的温度分布.结果表明,匙孔形成的主要驱动力是反冲压力,在加热初期,激光主要用来加热金属基体,随着激光辐照时间的增加,熔池表面温度急剧升高,金属进而汽化,产生匙孔.针对304不锈钢的工艺试验表明计算结果与实际相符合.
In order to accurately simulate the laser deep penetration welding process,a three-phase unification mathematical model of vapor phase,liquid phase and solid phase was established.The VOF(volume-of-fluid) method was employed to track free surfaces.Roles of surface tension,recoil pressure and thermal buoyancy were considered in the model.Dynamic process of keyhole and its corresponding temperature distributions were obtained by numerical modeling.The welding experiments on 304 stainless steel alloy show the calcutled results agree well with the experimental results.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2010年第11期38-40,共3页
Transactions of The China Welding Institution
关键词
激光深熔焊
匙孔
反冲压力
数值模拟
laser deep penetration welding
keyhole
recoil pressure
numerical simulation
