摘要
建立了超声场下激光熔凝过程中的数值模拟,采用模拟和实验相结合,分析了超声作用对熔池流动状态以及熔凝后熔池宏观形貌的影响。结果表明,未施加超声振动时熔池内部流动主要驱动力是温度梯度引起的表面张力和熔池自身重力引起的回流;施加超声振动时,熔池的流动状态随着超声振动发生周期性的改变,熔池内部声压承周期性的变化,最终使熔池的熔池宽度相对于未施加超声作用时缩减了19.2%,熔池深度伸展了30.8%,通过模拟和实验得出,在熔凝状态下熔池宏观形貌和模拟结果基本符合。
The numerical simulation of laser melting process under the ultrasonic field is established.The molten pool flow state and molten pool macroscopic morphology after melting under the influence of ultrasonic field are analysed by the combination of simulation and experiment.The result shows that the main driving force of the internal flow of molten pool is the surface tension caused by the temperature gradient and the reflux of molten pool caused by its own gravity when no ultrasonic vibration applied;The molten pool flow state and the acoustic pressure in the molten pool are changed cyclically with the ultrasonic vibration when the ultrasonic vibration applied.Ultimately,The breadth of the molten pool reduces by 19.2% and the depth increases by 30.8% compared with no ultrasonic vibration applied.It can be found that the numerical simulation results are basically consistent with molten pool macroscopic morphology under the state of laser melting through simulations and experiments.
出处
《应用激光》
CSCD
北大核心
2014年第3期204-210,共7页
Applied Laser
关键词
超声振动
熔凝
表面张力
熔池流场
ultrasonic vibration
melting
surface tension
flow field of molten pool
