Phase field simulation of dendrite growth in binary Ni–Cu alloy under the applied temperature gradient

Abstract

Phase field method was employed to investigate the effect of the applied temperature gradient on the microstructure evolution for the binary Ni–Cu alloy during the solidification process. As a comparison group, the isothermal solidification and the non-isothermal solidification taking into account the effect of latent heat were simulated at the same time. Simulation results showed that temperature distribution could greatly influence dendrite morphology, concentration distribution and tip velocity. Under the applied temperature gradient, a cone shape of dendrite, instead of the normal dendrite with four symmetric arms, could be found easily. The growth rate of dendrite and the segregation of concentration field increased with the increasing temperature gradient. This model was able to give a clear outlook for the influence of temperature gradient on the dendrite morphology and help a better design for the microstructure control in the field of direct chill casting.