Copper alloy suitable for an IC lead pin for a pin grid array provided on a plastic substrate

Abstract

A copper alloy suitable for an IC lead pin for a pin grid array provided on a plastic substrate, which copper alloy is a Cu—Zn—Mg alloy, a Cu—Sn alloy, a Cu—SN—Ag alloy, a Cu—Fe—Zn—P alloy, or a Cu—Cr alloy, each having a given alloy composition, in which the copper alloy has conductivity of 50% IACS or more and tensile stress of 400 MPa to 650 MPa.

What is claimed is:  
     
         1 . A copper alloy suitable for an IC lead pin for a pin grid array provided on a plastic substrate, which copper alloy is selected from the group consisting of: 
 a copper alloy containing 0.05 to 0.5 wt % of Zn and 0.05 to 0.5 wt % of Mg, with the balance being made of unavoidable impurities and Cu;    a copper alloy containing 0.1 to 1.0 wt % of Sn, with the balance being made of unavoidable impurities and Cu;    a copper alloy containing 0.1 to 1.0 wt % of Sn and 0.1 to 0.6 wt % of Ag, with the balance being made of unavoidable impurities and Cu;    a copper alloy containing 2.1 to 2.6 wt % of Fe, 0.05 to 0.2 wt % of Zn, and 0.015 to 0.15 wt % of P, with the balance being made of unavoidable impurities and Cu; and    a copper alloy containing 0.4 to 1.1 wt % of Cr, with the balance being made of unavoidable impurities and Cu,    wherein the copper alloy has conductivity of 50% IACS or more, and tensile stress of 400 MPa or more but 650 MPa or less.    
     
     
         2 . The copper alloy as claimed in    claim 1   , which is the copper alloy containing 0.05 to 0.5 wt % of Zn and 0.05 to 0.5 wt % of Mg, with the balance being made of unavoidable impurities and Cu.  
     
     
         3 . The copper alloy as claimed in    claim 1   , which is the copper alloy containing 0.1 to 1.0 wt % of Sn, with the balance being made of unavoidable impurities and Cu.  
     
     
         4 . The copper alloy as claimed in    claim 1   , which is the copper alloy containing 0.1 to 1.0 wt % of Sn and 0.1 to 0.6 wt % of Ag, with the balance being made of unavoidable impurities and Cu.  
     
     
         5 . The copper alloy as claimed in    claim 1   , which is the copper alloy containing 2.1 to 2.6 wt % of Fe, 0.05 to 0.2 wt % of Zn, and 0.015 to 0.15 wt % of P, with the balance being made of unavoidable impurities and Cu.  
     
     
         6 . The copper alloy as claimed in    claim 1   , which is the copper alloy containing 0.4 to 1.1 wt % of Cr, with the balance being made of unavoidable impurities and Cu.