In-Situ Precipitated nanocrystal Beneficial to Enhanced Plasticity of Cu-Zr Based bulk Metallic Glasses

A study was conducted to prepare a series of Cu₄₆Zr ₄₇Al₇ alloys with different microstructures, including full glassy structure and marginal BMG, containing small in-situ precipitated nanocrystals and BMG composite containing large CuZr crystals. Compression and bending tests were conducted, to evaluate plasticity of these composites. The effect of the nanocrystals on the plasticity of Cu-Zr-based BMG and its composites were systematically investigated. The tilt casting method in an arc furnace was used to prepare BMG and its composites. Electromagnetic string function was also introduced to the investigation, by adding a current loop under the water-cooled copper crucible. The alloy ingots with nominal compositions Cu₄₆Zr₄₇Al₇ were prepared by arc melting the mixtures of ultrasonically cleansed Zr, Cu, and Al pieces.