多元合金耦合热力学数据非等温凝固的相场模拟

研究一种多元合金的非等温相场模型，定量地模拟工业多元合金的真实凝固过程，结合热力学和扩散迁移率的数据来预测整个系统中的相平衡、溶质扩散系数、比热容和放出的潜热。结果表明：这些参数不是常数，它们的值与成分和温度有关。没有这些参数，定量模拟多元合金的凝固几乎是不可能。在这个模型中，界面区域假设是由有同样化学势的固相和液相混合而成的，但组成不同。这个模型中同样考虑反溶质截流。一并将模型应用到工业Al?Cu?Mg合金的各向枝晶自由长大的凝固过程。

Phase field simulation for non-isothermal solidification of multicomponent alloys coupled with thermodynamics database

In order to quantitively model the real solidification process of industrial multicomponent alloys, a non-isothermal phase field model was studied for multicomponent alloy fully coupled with thermodynamic and diffusion mobility database, which can accurately predict the phase equilibrium, solute diffusion coefficients, specific heat capacity and latent heat release in the whole system. The results show that these parameters are not constants and their values depend on local concentration and temperature. Quantitative simulation of solidification in multicomponent alloys is almost impossible without such parameters available. In this model, the interfacial region is assumed to be a mixture of solid and liquid with the same chemical potentials, but with different composition. The anti-trapping current is also considered in the model. And this model was successfully applied to industrial Al–Cu–Mg alloy for the free equiaxed dendrite solidification process.