Copper-beryllium alloy strip

Abstract

The yield strength of UNS C17460 BeCu alloy can be significantly enhanced without compromising electrical conductivity or bend formability by age hardening the alloy during manufacture using two separate heat treatment steps and cold rolling the alloy for enhancing age hardening response between these two heat treatment steps rather than before age hardening begins as in current technology.

1 . A copper-beryllium alloy comprising about 0.15 to 0.5 wt. % Be, about 0.35 to 1.40 wt. % Ni and/or Co, up to about 0.5 wt. % Zr, with the balance being copper and incidental impurities, wherein the alloy exhibits an electrical conductivity of at least 45% IACS, a bend formability of less than about 3 R/t in the longitudinal (Good Way) direction and less than 9 R/t in the transverse (Bad Way) direction, and a 0.2% yield strength of at least about 130 ksi.  
     
     
         2 . The alloy of  claim 1 , wherein the alloy has a bend formability of less than about 5 R/t in the transverse (Bad Way) direction.  
     
     
         3 . The alloy of  claim 2 , wherein the alloy has a bend formability of less than about 3 R/t in the transverse (Bad Way) direction.  
     
     
         4 . The alloy of  claim 3 , wherein the alloy has a 0.2% yield strength of at least about 140 ksi.  
     
     
         5 . The alloy of  claim 4 , wherein the alloy contains about 0.15 to 0.5 wt. % Be, about 1.0 to 1.40 wt. % Ni, up to 0.5 wt. % Zr and the balance Cu plus incidental impurities.  
     
     
         6 . The alloy of  claim 4 , wherein the alloy contains about 0.15 to 0.5 wt. % Be, about 0.35 to 0.60 wt. % Co and the balance Cu plus incidental impurities.  
     
     
         7 . The alloy of  claim 1 , wherein the alloy contains about 0.15 to 0.5 wt. % Be, about 1.0 to 1.40 wt. % Ni, up to 0.5 wt. % Zr and the balance Cu plus incidental impurities.  
     
     
         8 . The alloy of  claim 1 , wherein the alloy contains about 0.15 to 0.5 wt. % Be, about 0.35 to 0.60 wt. % Co and the balance Cu plus incidental impurities.  
     
     
         9 . The alloy of  claim 1 , wherein the alloy contains no more than about 0.5 wt. % of one or more of the following additional ingredients: Fe, Al, Si, Sn, Zn, Cr, V, Mo, Mn, W, Ag, Au, Ta, Nb, Ti, Hf, P, Mg, Ca, Se, Te, S and Pb.  
     
     
         10 . Alloy strip or wire made from the alloy of  claim 1 .  
     
     
         11 . Alloy strip or wire made from the alloy of  claim 4 .  
     
     
         12 . Alloy strip or wire made from the alloy of  claim 5 .  
     
     
         13 - 21 . (canceled)