Cu-Ni-Si SYSTEM ALLOY FOR ELECTRONIC MATERIALS

Abstract

An object of the present invention is to provide a Corson alloy having significantly improved characteristics, i.e. high strength and high electrical conductivity, by enhancing the effect of addition of Cr to a Cu—Ni—Si system alloy. There is provided a copper alloy for electronic materials comprising 1.0-4.5% by mass Ni, 0.50-1.2% by mass Si, 0.003-0.3% by mass Cr wherein the weight ratio of Ni to Si satisfies the expression: 3≦Ni/Si≦5.5, and the balance being Cu and incidental impurities, wherein particles of Cr—Si compounds having a size of 0.1 μm to 5 μm are dispersed in the alloy and the dispersed particles having an atomic concentration ratio of Cr to Si of 1 to 5 and a dispersion density of no more than 1×10 6 /mm 2 .

1 . A copper alloy for electronic materials, comprising 1.0-4.5% by mass Ni, 0.50-1.2% by mass Si, 0.003-0.3% by mass Cr wherein the weight ratio of Ni to Si satisfies the expression: 3≦Ni/Si≦5.5, and the balance being Cu and incidental impurities, wherein particles of Cr—Si compounds having a size of 0.1 μm to 5 μm are dispersed in the alloy, the dispersed particles having an atomic concentration ratio of Cr to Si in the range of 1 to 5 and a dispersion density of no more than 1×10 6 /mm 2 . 
     
     
         2 . The copper alloy for electronic materials according to  claim 1 , wherein the dispersion density of the particles of the Cr—Si compounds having a size of 0.1 μm to 5 μm is higher than 1×10 4 /mm 2 . 
     
     
         3 . The copper alloy for electronic materials according to  claim 1 , further comprising 0.05-2.0% by mass of at least one element selected from Sn and Zn. 
     
     
         4 . The copper alloy for electronic materials according to  claim 1 , further comprising 0.001-2.0% by mass of at least one element selected from Mg, Mn, Ag, P, As, Sb, Be, B, Ti, Zr, Al, Co and Fe. 
     
     
         5 . A wrought copper product comprising the copper alloy according to any one of  claims 1  to  4 . 
     
     
         6 . A component for electronic devices, comprising the copper alloy according to any one of  claims 1  to  4 .