Phase transformations play a key role in numerous coupled natural processes, and they are important for many industrial applications. However, the kinetics of phase transformations in coupled chemo-mechanical systems undergoing large mechanical deformations still needs to be better quantified. Here, we study the phase transformation kinetics of a two-phase binary mixture using the diffuse interface approach. We couple a Cahn–Hilliard type model with a mechanical model for a compressible viscous flow. The bulk compressibility is a nonlinear function of the pressure, and the shear viscosity is a nonlinear function of the concentration. The mechanical coupling is achieved by employing a pressure-dependent mechanical mixing term in the equation for the Gibbs energy. We derive a dimensionless system of equations which we solve numerically with a pseudo-transient method using conservative finite differences for discretization. We perform numerical simulations in 1D and 2D model setups considering far-field simple shear and pure shear. For a chemo-mechanically coupled system, we show that the velocity of the phase boundary is a linear function of the degree of metastability and, hence, confirm the hypothesis of “normal growth.” A stronger mechanical coupling and a larger volumetric effect of the chemical reaction result in lower phase boundary velocities. The 2D results show a significant impact of the mechanical coupling and the far-field deformation on the orientation and kinetics of the phase transformations. Under far-field simple shear and pure shear in 2D, the phase transformations generate string-like patterns. The orientation of these patterns is controlled by the applied far-field deformation and orientations differ by 45 degrees between simple shear and pure shear.

相变在许多耦合的自然过程中发挥着关键作用，并且对于许多工业应用都很重要。然而，经历大机械变形的耦合化学机械系统中的相变动力学仍然需要更好地量化。在这里，我们使用扩散界面方法研究两相二元混合物的相变动力学。我们将 Cahn-Hilliard 型模型与可压缩粘性流的力学模型结合起来。体积压缩性是压力的非线性函数，剪切粘度是浓度的非线性函数。机械耦合是通过在吉布斯能量方程中采用与压力相关的机械混合项来实现的。我们推导了一个无量纲方程组，并使用保守的有限差分法进行离散化，通过伪瞬态方法对其进行数值求解。我们在考虑远场简单剪切和纯剪切的一维和二维模型设置中进行数值模拟。对于化学机械耦合系统，我们证明相界速度是亚稳态程度的线性函数，因此证实了“正常生长”的假设。更强的机械耦合和更大的化学反应体积效应导致更低的相界速度。二维结果显示机械耦合和远场变形对相变的方向和动力学有显着影响。在二维远场简单剪切和纯剪切下，相变产生类似弦的图案。这些图案的方向由所施加的远场变形控制，并且简单剪切和纯剪切之间的方向相差 45 度。