Synthesis of Amorphous/Crystalline Laminated Metals via Accumulative Roll Bonding

Bulk metallic glasses (BMG) are best known for their high strength and hardness; however, due to their limited tensile plasticity, they are undesirable for many structural applications. Nano-laminated amorphous/crystalline metals fabricated via deposition techniques have been shown to deform homogeneously while demonstrating extraordinary mechanical properties, including high strength and ductility; however, their fabrication is limited in size and scalability potential. Here, accumulative roll bonding has been demonstrated as a scalable fabrication technique for the processing of nanolaminated Zr-based BMG/Ni composites. The rolling was performed at elevated temperatures, utilizing the thermoplastic formability of the BMG in its supercooled liquid region. Microhardness measurements were utilized to investigate the thermo-mechanical history of the BMG phase. Refined BMG layers with thicknesses as small as 34nm have been characterized using transmission electron microscopy techniques. The resulting amorphous/crystalline interface has been demonstrated to have an effective interface width of 3-4nm.