Plasticity enhancement in bulk metallic glasses by electroless plating with Ni-P amorphous films

Abstract In this study Electroless plating is used to deposit amorphous Ni-P films on the surface of the Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 (Vit.1) bulk metallic glasses (BMGs) with different pH values and film thicknesses. The special amorphous/amorphous structure exhibited large plasticity. The plastic strain is 10.6% for the coated pillars with a coating thickness of 86.5 μm, which is 5.9 times of 1.8% of the bare Vit.1 pillars. The amorphous Ni-P films provide high radial confinement stress, which leads to more homogeneous formation of a high density of smaller shear bands at the Ni-P/Vit.1 interface. The technique provides an effective way to enhance the plasticity without obvious sacrifice of the yielding strength for BMGs at room temperature.