ABSTRACT A numerical model that incorporates variable diffusion coefficient is used to study and compare the kinetics of solute penetration during diffusion-controlled isothermal solidification and homogenisation stages of transient liquid phase (TLP) bonding in planar and non-planar (cylindrical and spherical) systems. The study reveals new information regarding key differences between the two stages, depending on whether the diffusion coefficient is constant or varies with composition. Notwithstanding the fact that non-planar solid–liquid interfaces cause the solute penetration to depart from a linear relationship with , known as parabolic-law behaviour, during isothermal solidification, the penetration kinetics in all the systems follow the parabolic-law during the homogenisation stage, when the diffusivity is constant. Moreover, in the planar system, while a variation of diffusivity with concentration does not alter the solute penetration kinetics through deviation from the parabolic-law behaviour during the isothermal solidification, it causes a deviation during the homogenisation stage.

中文翻译：

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瞬态液相键合的等温凝固和均化阶段扩散动力学的比较

摘要 结合可变扩散系数的数值模型用于研究和比较平面和非平面（圆柱形和球形）系统中瞬态液相 (TLP) 键合的扩散控制等温凝固和均化阶段溶质渗透的动力学。该研究揭示了关于两个阶段之间关键差异的新信息，这取决于扩散系数是恒定的还是随成分而变化的。尽管非平面固液界面导致溶质渗透偏离线性关系，称为抛物线行为，在等温凝固过程中，所有系统中的渗透动力学在均质化阶段遵循抛物线规律，当扩散系数恒定时。而且，