Phase-field Method Simulation Of Fe-C Alloy In Dendritic Growth Process

As basic structure of metal dendrite crystal,the dendrite growth process played a decisive role in the formation of solidification structure.As a new subject,the microstructure numerical simulation attracted lots of scientists attention,which has the unique advantages in simulations of metal dendrite growth and the formation of castings.Not only supplement the metal solidification theory effectively,it also can guide the actual production process to reduce the cost.In this paper,the modified Phase-field model was used to study these following fields of Fe-C alloys.(1)the dendrite growth process in 3D was simulated by the modified Phase-field model.The effect of Phase-field parameters,including the interface width,relaxation time,on dendrite growth process and dendrite morphology were investigated based on Phase-field theory,and then the appropriate parameters were chosen and used in following simulations.(2)the similar results were achieved in the simulation of equiaxed dendrite growth compared with the experimental results,and changes of dendrite tip parameters were consistent with existing dendrite growth theories.Quantitative studies of undercooling effect on dendrite tip parameters were achieved by controlling dendrite tip supersaturation.(3)Isothermal solidification of equiaxed dendrite in 3D was simulated by Phase-field method.The interface anisotropy effect on dendrite growth process were investigated by Phase-field model,which coupled interfacial energy anisotropy,and Dendrite Orientation Transformation of Fe-C alloy in equiaxed dendrite was simulated successfully.(4)The dendrite growth process in directional solidification was investigated,the effect of directional solidification parameters,the pulling speed and temperature gradient,on dendrite growth process.Directional solidification process of different solute Fe-C alloys were investigated by adjusting interfacial energy anisotropy coefficients,the liquid channel and solute segregation during directional solidification were simulated successfully,and the systematically studies of the directional solidification parameters effect on formation of liquid channel and dendrite morphology were carried out.