Copper, copper alloy, and manufacturing method therefor

Abstract

Copper and copper alloy comprises: a structure having fine crystal grains with grain size of 1 μm or less after a final cold rolling with a reduction η, wherein η is expressed in the following formula and satisfying η≧3; and an elongation of 2% or more in a tensile test. η=ln( T 0 /T 1 ) T 0 : plate thickness before rolling, T 1 : plate thickness after rolling.

1 . A copper alloy comprising:
 a dynamic continuous recrystallization structure having fine crystal grains with grain size of 0.4 cm or less composed of crystal grain boundaries that are round and uniform and are caused by a final cold rolling, and   an elongation of 2% or more in a tensile test;   wherein the copper alloy is a Cu—Ni—Si alloy consisting of 1.0 to 4.8 mass % of Ni, 0.2 to 1.4 mass % of Si, and balance of Cu and inevitable impurities, and   wherein the dynamic continuous recrystallization structure is formed by   casting ingots of copper alloy;   hot-rolling the ingots to form plates;   processing the plates by performing one or more treatments selected from the group consisting of solid solution treatments, recrystallization annealing treatments and aging treatments; and   cold-rolling the plates.   
     
     
         2 . The copper alloy according to  claim 1 , wherein the alloy further contains 0.005 to 2.0 mass % in total amount of at least one of Sn, Fe, Ti, P, Mn, Zn, In, Mg and Ag. 
     
     
         3 . The copper alloy according to  claim 1 , wherein the final cold rolling was performed with a reduction η, wherein η is expressed in the following formula and satisfying η≧ 3     η=ln( T   0   /T   1 )   
       T 0 : plate thickness before rolling, T 1 : plate thickness after rolling. 
     
     
         4 . The copper alloy according to  claim 1 , wherein the copper alloy was produced by stress relief annealing, and has an elongation of 6% or more by a tensile test. 
     
     
         5 . A copper alloy comprising:
 a dynamic continuous recrystallization structure having fine crystal grains with grain size of 0.4 μm or less composed of crystal grain boundaries that are round and uniform and are caused by a final cold rolling, and   an elongation of 2% or more in a tensile test;   wherein the copper alloy is a Cu—Cr—Zr alloy consisting of 0.02 to 0.4 mass % of Cr, 0.01 to 0.25 mass % of Zr, and balance of Cu and inevitable impurities, and   wherein the dynamic continuous recrystallization structure is formed by   casting ingots of copper alloy;   hot-rolling the ingots to form plates;   processing the plates by performing one or more treatments selected from the group consisting of solid solution treatments, recrystallization annealing treatments and aging treatments; and   cold-rolling the plates.   
     
     
         6 . The copper alloy according to  claim 5 , wherein the alloy further contains 0.005 to 2.0 mass % in total amount of at least one of Sn, Fe, Ti, P, Mn, Zn, In, Mg and Ag. 
     
     
         7 . The copper alloy according to  claim 5 , wherein the final cold rolling was performed with a reduction η, wherein η is expressed in the following formula and satisfying η≧3
   η=ln( T   0   /T   1 )   
       T 0 : plate thickness before rolling, T 1 : plate thickness after rolling. 
     
     
         8 . The copper alloy according to  claim 5 , wherein the copper alloy is produced by stress relief annealing, and has an elongation of 6% or more by a tensile test.