| 摘要: |
| 建立了激光-等离子弧复合焊接过程中液相区、糊状区和固相区的统一模型,在模型中同时考虑了表面张力、热浮力和电磁力的作用,通过数值计算得到了熔池的速度场和温度场,重点研究了电磁力对熔池流动和传热的影响。结果表明,在熔池形成的初始阶段,表面张力对熔池中的对流和传热起主要作用,而电磁力的作用受到抑制,随着熔深增加,电磁力作用增强并引起涡旋,导致熔深和下表面熔宽增加。针对1420铝锂合金的复合焊工艺试验表明计算结果与实际相符合。 |
| 关键词: 激光-等离子弧复合焊接 对流传热 数值分析 铝合金 |
| DOI： |
| 分类号: |
| 基金项目:高等学校博士学科专项科研基金资助项目(20050003041);国防科技重点实验室基金资助项目(514610105005JW120) |
|
| Numerical simulation on flow and heat transfer in weld pool of laser-plasma hybrid welding |
|
LI Zhining, DU Dong, CHANG Baohua, WANG Li
|
|
Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Tsinghua University, Beijing 100084, China
|
| Abstract: |
| A unified model is establtshed for the liquid zone, mushy zone and solid zone during laser-plasma hybrid welding, which takes into account the surface tension, heat buoyancy and electromagnetic force in the welding pool. The velocity and temperature distributions in weld pool were numerically computed to study the effect of electromagnetic force on the flow and convection heat transfer in weld pool. Results show that the electromagnetic force's effect is negligible and the surface tension is predominant at the initial formation phase of weld pool. With the increasing of the depth of weld pool, the eddy induced by electromagnetic force appears at the bottom of weld pool and results in deeper and wider weld pool. The hybrid welding experiments on 1420 Al-Li alloy show that the computational results agree well with experimental results. |
| Key words: laser-plasma arc hybrid welding convection heat transfer numerical analysis aluminum alloy |
