INSTABILITY OF METASTABLE SOLID-SOLUTIONS AND CRYSTAL TO GLASS-TRANSITION

Crystal to glass transitions are simulated using molecular dynamics for an fcc binary random solid solution with varying atomic size ratios and concentrations. The transition occurs at a critical supersaturated solute concentration with a sufficiently large solute-solvent atomic size difference. Close to the amorphization, the shear elastic moduli become dramatically softened, accompanied by a martensite-like structural change. Large strain fluctuations and small enthalpy and volume changes at the transition indicate that it is triggered by a mechanical instability reached in the metastable crystal.