Strain burst speeds in metallic glass micropillars

Uniaxial microcompression and nanoscratch tests using the nanoindentation system on the Mg-, Au- and Zr-based metallic glass micropillars with diameters of 3.8 and 1 μm were performed and compared. Strain burst phenomena were observed in all microcompression tests as indications of localized shearing. The strain burst speed of micropillars can be measured based on the raw displacement-time profile. The results indicate that strain burst speed of metallic glasses increases with increasing sample size, with decreasing wear resistance, and with decreasing ductility. The current study demonstrates that strain burst speed and wear characteristics can be regarded as promising indicators for the ductility of metallic glasses.