Stress-Induced Virtual Melting as a New Mechanism of Solid-Solid Phase Transformations and Stress Relaxation

我们最近预测了一个新的现象，即晶体-晶体和晶体-非晶相变可以通过在纳米尺度层沿着界面在显著的温度下（超过1000 K！）低于热力学熔化温度。大的相变应变引起的内弹性应力的能量增加了熔化的驱动力，降低了熔化温度。熔化释放应力，并且不稳定的熔体立即固化成稳定的结晶（高于玻璃化转变温度）或非晶（低于玻璃化转变温度）相。因此，虚拟熔化代表了一种新的机制，在移动的固-固界面的固-固转变，应力松弛和损失的相干性。该项目的目标是开发理论，计算和实验方法，使我们能够证明存在，研究主要特征，探索通过虚拟熔化的固-固转变现象的普遍性和应用意义。

We recently predicted a new phenomenon, namely that crystal-crystal and crystal-amorphous phase transformations can occur via virtual melting in the nanoscale layer along the interface at temperatures significantly (more than 1000K!) below the thermodynamic melting temperature. The energy of the internal elastic stresses, induced by large transformation strain for solid-solid transformation, increases the driving force for melting and reduces the melting temperature. Melting releases the stresses and the unstable melt immediately solidifies into the stable crystalline (above the glass transition temperature) or amorphous (below the glass transition temperature) phase. Thus, virtual melting represents a new mechanism of solid-solid transformations, stress relaxation and loss of coherency at a moving solid-solid interface. The goal of this project is to develop theoretical, computational, and experimental approaches that will allow us to prove the existence, to study main features and explore the generality and applied significance of the phenomena of solid-solid transformations via virtual melting.