Mg-based bulk metallic glass composites with plasticity and high strength

Composite alloys of (Mg0.65Cu0.075Ni0.075Zn0.05Ag0.05Y0.1)100−xFex(x=9 and 13) have been produced through copper mold casting, based on a good bulk metallic glass former. Upon cooling the melt, an α-Fe solid solution precipitates uniformly with sizes in the 1–10 μm range while the remaining melt undergoes a glass transition. The in situ composite has a compressive strength as high as ∼1 GPa, a factor of 1.6 higher than the single-phase metallic glass. In contrast to all the previous Mg-based monolithic glasses that always fail in the elastic regime, a plastic strain to failure of the order of 1% was obtained for the Fe-toughened composite.