Patent ID: 7399370

Claim:
A Cu-based amorphous alloy product, comprising 90 percent by volume or more of amorphous phase having a composition represented by a first formula: Cu 100-a-b (Zr,Hf) a (Al,Ga) b , where a and b are on an atomic percent basis and satisfy 35≦a ≦45 and 2≦b ≦10, wherein the amorphous phase contains 50 to 60 atomic percent of Cu, wherein the temperature interval ΔTx of supercooled liquid region is 45 K or more, the temperature interval being represented by a second formula: ΔTx=Tx−Tg, where Tx represents a crystallization initiation temperature and Tg represents a glass transition temperature, said product having a diameter or thickness of 1 mm or more and a volume fraction of amorphous phase of 90% or more is produced by a metal mold casting method, the compressive strength is 1,900 MPa or more, the Young's modulus is 100 GPa or more, and the Vickers hardness is 500 Hv or more.