Evaluation of hardness–yield strength relationships for bulk metallic glasses

Abstract

The applicability of various hardness–yield strength (H − σ_y ) relationships currently available in the literature for bulk metallic glasses (BMGs) is investigated. Experimental data generated on ZrHf-based BMGs in this study and those available elsewhere on other BMG compositions are used to validate the models. A modified expanding-cavity model, proposed earlier by the authors, is extended to propose a new H − σ_y relationship. Unlike previous models, the proposed model takes into account, not only the indenter geometry and the material properties, but also the pressure sensitivity index of the BMGs. The influence of various model parameters is systematically analyzed. It is shown that there is a good correlation between the model predictions and experimental data for a wide range of BMG compositions.