Activation volume in heterogeneous deformation of Mg65Cu12.5Ni12.5(Ce75La25)10 metallic glass.

Depth variation at constant load in instrumented nano-indentation was used to measure activation volume controlling shear band formation in the Mg65Cu12.5Ni12.5(Ce75La25)10 metallic glass. A series of measurements revealed a large scattering of the data spanning from 100 Å3 to 800 Å3. The distribution of values, which is not following a normal one, may be attributed to the atomic structure of metallic glasses with the absence of long range order, leading to different volume fraction of shear bands for independent experiments. Activation volume is analyzed considering the variation of shear band volume fraction leading to a unique value of a true activation volume. An interpretation for the distribution of values is proposed. [ABSTRACT FROM AUTHOR]