Synthesis and mechanical behavior of nanocomposite Mg-based bulk metallic glasses

摘要

Nanocomposites can be produced by partial crystallization of bulk metallic glasses (BMG). The introduction of such nanocrystals in an amorphous matrix can sharply change the mechanical behavior of the glass at room temperature. In the present study, the effect of crystals in Mg-based BMG is studied by partial crystallization of the Mg_(0.5)Cu_(25)Gd_(10) and addition of 3 at.% of iron. Various techniques (DSC, DRX, TEM) are used to get data about the nature, the volume fraction or the average size of the crystals. Mechanical properties at room temperature are investigated in compression. The fracture stress is enhanced by iron addition, but no favorable effect of partial crystallization is observed for the Mg_(65)Cu_(25)Gd_(10) BMG. These results are discussed in relation with the associated microstructures.