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.