Deformation of Nanoglass under High-pressure Torsion

Abstract

Metallic glasses are amorphous solids with metallic atomic bonds. Different from traditional crystalline metals, they have no long-range atomic order. Only short-range order on the scale of 0.5–1 nm can be detected [1-4]. Because of the lack of a lattice dislocation slip system, as in crystalline alloys, metallic glasses exhibit some outstanding properties, such as high elastic strain, high hardness and high strength [5-7]. The yield strengths of Zr-based bulk metallic glasses (BMGs) are approximately 2 GPa in compression. Unfortunately, this special structure also creates problems; that is, plastic deformation in BMGs is always concentrated in localized regions, namely, shear bands, resulting in catastrophic failure [8]. This brittleness restricts their industrial applications. Zr64Ni10Al7Cu19 is a BMG system [9,10] with good glass forming ability and high strength but no plastic strain under tensile testing.