Co-Ni-base alloy

Abstract

A Co—Ni-base alloy, being characterized in that a composition of the alloy comprises at least Co, Ni, Cr, Mo, W and Fe, and percentages by weight of the composition are from 25% to 45% of Co, from 25% to 40% of Ni, from 18% to 26% of Cr, from 3% to 11% of Mo, from 0.5% to 9% of W, wherein a sum of Mo and W is from 4% to 13% by weight, and from 1.1% to 5% of Fe.

1 . A Co—Ni-base alloy, being characterized in that a composition of the alloy comprises at least Co, Ni, Cr, Mo, W and Fe, and percentages by weight of the composition are from 25% to 45% of Co, from 25% to 40% of Ni, from 18% to 26% of Cr, from 3% to 11% of Mo, from 0.5% to 9% of W, wherein a sum of Mo and W is from 4% to 13% by weight, and from 1.1% to 5% of Fe.  
     
     
         2 . The Co—Ni-base alloy as set forth in  claim 1 , being characterized in that the composition of the alloy comprises one type or more of elements among Nb, Mn, B, Zr and Ti, and percentages by weight of the elements contained in the alloy are as follows: 
 0≦Nb≦2%,; 0≦Mn≦2%; 0≦B≦0.02%; 0≦Zr≦0.2%; and 0≦Ti≦1%.    
     
     
         3 . The Co—Ni-base alloy as set forth in  claim 1  or  2 , being characterized by having been subjected to cold-plastic working.  
     
     
         4 . The Co—Ni-base alloy as set forth in  claim 3 , being characterized in that a processing ratio of the cold-plastic working is 50% or more.  
     
     
         5 . The Co—Ni-base alloy as set forth in anyone of claims  1 , and  2 , being characterized by having been subjected to an age-hardening treatment.  
     
     
         6 . The Co—Ni-base alloy as set forth in  claim 5 , being characterized in that a temperature of the age-hardening treatment is from 200° C. to 700° C.  
     
     
         7 . The Co—Ni-base alloy as set forth in any one of claims  1  and  2  being characterized by having fine deformation twins in a parent phase.  
     
     
         8 . A mainspring, being characterized by comprising the Co—Ni-base alloy as set forth in any one of claims  1  and  2 .  
     
     
         9 . A method for producing a mainspring comprising the steps of: 
 mixing elements such that a composition of an alloy comprises, in terms of percentages by weight, from 25% to 45% of Co, from 25% to 40% of Ni, from 18% to 26% of Cr, from 3% to 11% of Mo, from 0.5% to 9% of W, wherein a sum of Mo and W is from 4% to 13% by weight, and from 1.1% to 5% of Fe and melting the alloy;    subjecting the alloy to cold-wire-drawing;    cold-rolling the alloy;    forming the alloy; and    subjecting the alloy to an age-hardening treatment.    
     
     
         10 . The method for producing the mainspring as set forth in  claim 9 , being characterized in that a processing ratio of the cold-wire-drawing is 10% or more in terms of a reduction ratio in a cross-section area.  
     
     
         11 . The method for producing the mainspring as set forth in  claim 9 , being characterized by performing the age-hardening treatment at a treating temperature of from 400° C. to 700° C. in a vacuum or non-oxidation atmosphere.