摘要
建立了复合热源作用下的激光穿透焊接熔池流动三维计算模型,热源由作用在激光表面的高斯热源以及沿激光入射方向的柱状热源组成,分别考虑了等离子体和小孔吸收机制。通过添加源项的办法解决了过渡区相变问题,从而将固态区和液态区组合一起求解,简化了固液边界条件的处理难度。通过TC1钛合金激光焊接试验验证了模型的正确性,计算所得的熔池截面与试验结果吻合良好。结果表明,Marangoni对流是形成激光穿透焊“沙漏”状熔池形貌的主要原因。
A three-dimensional mathematical model for the temperature field and flow field in full penetration laser welding of titanium alloy was presented. In this model, the heat source comprises a plane heat source on the top surface and a cylindrical heat source along the z-direction, which takes into account the plasma effect and the keyhole absorption. The mushy region is introduced to provide a simple method to dispose the pressure and velocity boundary conditions. Calculated results are found to agree with the experimental results for the geometry profile of weld. The metal flow is the main cause for forming the typical hourglass cross-section profile.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2005年第12期65-68,100,共5页
Transactions of The China Welding Institution
关键词
激光焊接
温度场
流动场
数值模拟
Absorption
Boundary conditions
Computer simulation
Flow of fluids
Mathematical models
Plasmas
Pressure
Temperature
Three dimensional
Titanium alloys
Velocity
