论文标题
远程平衡合金固化期间的微观结构模式形成
Microstructural Pattern Formation during Far-from-Equilibrium Alloy Solidification
论文作者
论文摘要
我们引入了快速合金固化的新相位场公式，该公式在非常广泛的界面速度上定量地融合了固液界面的非平衡效应。仿真确定了溶质捕获驱动的速度驱动的树突尖端生长的新动力不稳定性，该速度接近绝对稳定性极限。他们还重现了广泛观察到的带子微观结构的形成，揭示了这种不稳定性如何触发树突状和无微粒凝固之间的过渡。预测的频带间距与迅速固化的al-Cu薄膜的观测数量一致。
We introduce a new phase-field formulation of rapid alloy solidification that quantitatively incorporates nonequilibrium effects at the solid-liquid interface over a very wide range of interface velocities. Simulations identify a new dynamical instability of dendrite tip growth driven by solute trapping at velocities approaching the absolute stability limit. They also reproduce the formation of the widely observed banded microstructures, revealing how this instability triggers transitions between dendritic and microsegregation-free solidification. Predicted band spacings agree quantitatively with observations in rapidly solidified Al-Cu thin films.
