研究了二元非均匀体系扩散的非线性动力学离散模型与Fick扩散定律和Cahn-Hilliard扩散方程的相关性。二元非均匀体系非线性动力学离散模型中，因原子的扩散系数与局部原子浓度强相关，扩散非对称性系数m’和有序能V是主要影响参数。采用非线性动力学离散模型和Cahn-Hilliard扩散方程分别计算了调制周期4.8 nm、9.6 nm和48 nm的Mo/V纳米多层薄膜的互扩散行为。Fick扩散定律和Cahn-Hilliard扩散方程等经典扩散定律和非线性动力学离散模型均可合理描述较大扩散尺度的扩散，随着扩散尺度的减小，经典扩散定律偏差逐渐增大，纳米尺度下的扩散需用非线性动力学离散模型描述。
Correlation of the nonlinear kinetic discrete model for diffusion in binary nonuniform system and Fick’s laws and Cahn-Hilliard equation is discussed. The diffusion asymmetry coefficients m’ and the ordering energy V in the nonlinear kinetics discrete model are the main influencing factor due to the strong concentration dependence of the diffusion coefficient in the binary nonuniform system. The concentration profiles of Mo/V multilayers with modulation wavelength 4.8 nm, 9.6 nm and 48 nm were calculated by the nonlinear kinetic discrete model and Cahn-Hilliard equation. It is found that classical diffusion law of Fick’s laws and Cahn-Hilliard equation and the nonlinear kinetic discrete model are valid for description of diffusion for all diffusion scale, whereas error of classical diffusion Law increases gradually with decreasing of diffusion scale, only the nonlinear kinetic discrete model is valid for description of diffusion in nano scale.
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