On the applicability of a mesoscopic interface sliding controlled model for understanding superplastic flow in bulk metallic glasses

• The model involves no adjustable parameters.
• Data pertaining to 8 systems are used to validate the model.
• Agreement between theory and experiments is very good.
• Prime novelty statement: “Superplasticity in metallic glasses explained by mesoscopic interface sliding”.

It is demonstrated that a mesoscopic interface sliding controlled flow model, which has already been shown to account for superplastic deformation in different types of crystalline materials, is also capable of describing superplastic flow in bulk metallic glasses. The only difference is that the random high-angle grain boundaries in crystalline materials along which deformation is concentrated, have to be replaced by the transient interfaces which are formed by interconnecting shear transformation zones in the region of homogeneous flow in bulk metallic glasses. Comparison with experimental results concerning superplastic flow in eight bulk metallic glasses shows that the numerical solutions obtained in the paper for the transcendental stress–strain rate equation of superplastic deformation lead to accurate predictions.

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