激光深熔焊熔池动力学特性理论分析

探讨了激光深熔焊过程中焊接熔池流体流动的各种驱动力,分析了熔池流动热边界层和固液界面粘性边界层的作用,研究了激光小孔出口的等离子体焰流对熔池Marangoni流的影响.

The Theoretical Analysis of the Hydrodynamic Properties in Deep Penetration Laser Welding

The purpose of this work is to understand the motive forces of the weld pool formation in deep penetration laser welding processing. The role of the temperature boundary layer of the gas flow in laser keyhole and viscosity boundary layer of liquid-solid boundary in laser welding pool is analyzed. The driving forces of fluid flow and the effect of plume above laser keyhole on Marangoni are studied. The viewpoint that the role of the plasma in laser keyhole is temperature term in the physical models is clarified. A basic mathematical model dynamically of physical fluid flow in deep penetration laser welding taking account of effects of incident laser power density is developed. The thermal conditions at the two boundaries in the problem (one between the keyhole and the molten metal, and the other between the liquid and the plume) are considered.