Extracting compressive stress-strain curve based on stick-slip shear banding process in bulk metallic glasses

摘要

Based on the stick-slip process,an effective method to extract the stress-strain curve directly from the crosshead displacement-load raw data in compression of bulk metallic glasses was proposed.The method was tested in two bulk metallic glass samples with different plasticities and shear band morphologies.The extracted stress-strain curves were found to well resemble the stress-strain curve measured by a laser extensometer.In addition,the extracted curve could resolve fine structures of serrated flow much better than that measured by extensometer,thus facilitating the study of shear banding process.Results obtained by this method made the stick-slip dynamics of shear banding valid,and this method could be employed to obtain the real strain of small-sized metallic glass samples where extensometer cannot be applied.