Numerical simulation of temperature field on laser metal deposition shaping

In order to decrease the thermal stress during process,based on the "element life and death" technique of finite element method(FEM),detailed numerical simulation of 3-D multi-track and multi-layer temperature field during laser metal deposition Shaping(LMDS) process was conducted with ANSYS parametric design language(APDL).Through those simulation,the dynamic variation of temperature in model reappeared,and the distribution rule of temperature and temperature gradient was obtained.The calculated results show that although the nodes on longitudinal section have different activated time,they have similar temperature variation history;the temperature gradients in sample are mainly along z direction,and the temperature gradients in substrate are mainly parallel to substrate.Under the same conditions,the SEM photos of samples tallies closely with the simulations results.