Method for producing an amorphous alloy having excellent strength

A method for producing an amorphous alloy, comprising the steps of:

• pressure-solidifying a molten alloy having a amorphous forming ability under a pressure exceeding one atmospheric pressure to eliminate casting defects so as to form an ingot with a thickness of 2 mm to 10 mm;
• adjusting a cooling rate 20 to 50% less than the critical cooling rate of the alloy during the solidification to disperse fine crystals having a mean crystal grain diameter of 2 μm to 50 μm and a volume percentage of 10 to 40% and not to precipitate large metallic compounds in an amorphous alloy ingot, to thereby impart a uniform residual compressive stress in the amorphous alloy ingot;
• heating the amorphous alloy ingot at a constant temperature rising rate;
• and
• infiltrating at least one of boron, carbon, oxygen, nitrogen and fluorine from the surface of the amorphous alloy ingot in a supercooled liquid state before crystallization, to thereby precipitate a high melting point compound thereof with an element forming the amorphous alloy within the alloy ingot for generating surface residual compressive stress so as to strengthen the alloy.