Process and apparatus for producing metallic glass

Abstract

A process and an apparatus for producing metallic glass which are capable of producing a bulk amorphous alloy of desired shape, in particular, a bulk amorphous alloy of desired final shape are provided. In the present invention, the molten metal at a temperature above the melting point is selectively cooled at a rate higher than the critical cooling rate, and the product comprises single amorphous phase which is free from the crystalline phase formed by the development of crystal nuclei through nonuniform nucleation. The present invention is capable of producing the bulk amorphous alloy which is free from casting defects such as cold shuts and which has excellent strength properties in a simple process at a high reproducibility. Accordingly, a bulk metallic glass of desired shape is produced by filling a metal material in a hearth; melting the metal material by using a high-energy heat source which is capable of melting the metal material; pressing the molten metal at a temperature above the melting point of the metal material to deform the molten metal into the desired shape by at least one of compressive stress and shear stress at a temperature above the melting point, while avoiding the surfaces of the molten metal cooled to a temperature below the melting point of the metal material from meeting with each other during the pressing; and cooling the molten metal at a cooling rate higher than the critical cooling rate of the metal material simultaneously with or after the deformation to produce the bulk metallic glass of desired form.

Dependencies are inferred from the claim text.