Solidification of laser deposition shaping for TC4 alloy based on cellular automation

Solidification process of molten pool during laser deposition shaping (LDS) were investigated to simulate the temperature transient and microstructural evolution for TC4 alloy with grain nucleation and growth model based on cellular automation method. The experiments conducted on the corresponding process parameters were compared with the simulation results and the microstructures were analyzed. The results showed that microstructure in the molten pool preferred to form coarse β columnar grains and acicular α′ martensite among the intracrystalline. The direction of grain growth was found to be opposite to the temperature transient, and the columnar grain trends to transform equiaxed microstructure. In the solidification process of molten pool, the preferred orientation of grain growth was 〈110〉 direction. Finally, it is verified that the simulation results agree well with the experimental results.