Interfacial strain concentration and relaxation along crystalline-amorphous boundaries of B2-reinforced bulk-metallic-glass-composites during loading

Interfacial stress concentration promotes both martensitic transformation nucleation and shear band initiation in B2-reinforced bulk-metallic-glass-composites. As the martensitic transformation occurs in the crystalline (soft) regime, shear bands are often observed in the amorphous (hard) matrix. A long-standing question has been when the stress concentration will prompt the martensitic transformation and when it will give rise to shear band initiation. By definition, stress concentration results from the regional Young's modulus multiplied by the local strain concentration. The localized strain concentration along crystalline-amorphous boundary plays decisive roles in promoting phase transformation and localized shear events. By constantly tracking the interfacial strain distribution through Molecular Dynamics methods, the location and magnitude of the interfacial strain concentration and its relaxation are quantified and correlated with the regional modulus differences. We are proposing that the regional strain concentration and relaxation is always located along soft/hard domains during loading so as to maintain the compatibility of interfacial deformation.