Sample size effects on strength and deformation mechanism of Sc75Fe25 nanoglass and metallic glass

Nanoglasses were a new type of amorphous materials and their microstructure consists of glassy regions (“grains”) with average size of ~ 10 nm and glass/glass interfaces (GGIs) between these glassy grains with widths of ~ 1 nm. A locally reduced density in the GGIs relative to the density of the glassy grains indicates that the GGIs in nanoglasses have an atomic structure which deviates from the rapidly-quenched metallic glass. For nanoglass, the existence of a large number of GGIs benefits for shear band nucleation and the subsequent multiple shear banding. While for submicron MG sample, there is not enough free space among the shear band nuclei for growing into a mature shear band.128