论文标题
非等热烧结过程的变异定量相田间建模
Variational quantitative phase-field modeling of nonisothermal sintering process
论文作者
论文摘要
在这项工作中,我们提出了一个非等温烧结过程的变分和定量相位模型。该模型是通过扩展的非对抗相位场模型得出的。模型演化方程在保守的动力学(即质量和热传递)和非保守的一个(晶粒生长)之间具有自然的交叉耦合项。通过渐近分析显示了这些术语,该术语在确保消除界面伪像的同时也对不修改热力学平衡条件(以二面角为特征)进行了检查。此外,我们证明了保护定律中表面扩散的陷阱效应和存在是方向依赖的。讨论了动力学迁移率的各向异性插值方案,该方案分化了沿界面的正常方向和切向方向。从数值上讲,我们通过呈现热微观结构的演变来证明交叉耦合和各向异性插值的重要性。
In this work, we present a variational and quantitative phase-field model for non-isothermal sintering processes. The model is derived via an extended non-diagonal phase-field model. The model evolution equations have naturally cross-coupling terms between the conserved kinetics (i.e., mass and thermal transfer) and the non-conserved one (grain growth). These terms are shown via asymptotic analysis to be instrumental in ensuring the elimination of interface artefacts, while also examined to not modify the thermodynamic equilibrium condition (characterized by dihedral angle). Moreover, we demonstrate that the trapping effects and existence of surface diffusion in conservation laws are direction-dependent. An anisotropic interpolation scheme of the kinetic mobilities which differentiates the normal and the tangential directions along the interface is discussed. Numerically, we demonstrate the importance of the cross-couplings and the anisotropic interpolation via presenting thermal-microstructural evolutions.