Soft copper alloy, and soft copper wire or plate material

Abstract

A method of fabricating soft copper alloy wire having flexure resistance and heat resistance, includes casting a molten alloy of a copper alloy including 10 mass ppm or less of oxygen, and 0.005 mass % to 0.6 mass % of indium, at a predetermined temperature, to provide a cast bar of the copper alloy having equiaxed crystal, rolling the cast bar of the copper alloy having equiaxed crystal to provide a rolled copper alloy, and conducting a cold drawing and annealing on the rolled copper alloy.

1 . A method of fabricating soft copper alloy wire having flexure resistance and heat resistance, comprising:
 casting a molten alloy of a copper alloy comprising 10 mass ppm or less of oxygen, and 0.005 mass % to 0.6 mass % of indium, at a predetermined temperature, to provide a cast bar of the copper alloy having equiaxed crystal;   rolling the cast bar of the copper alloy having equiaxed crystal to provide a rolled copper alloy; and   conducting a cold drawing and annealing on the rolled copper alloy.   
   
   
       2 . The method for fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein a temperature of molten alloy in casting is 10° C. to 50° C. greater than a melting temperature of the copper alloy. 
   
   
       3 . The method for fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein the copper alloy further comprises 0.0001 mass % to 0.003 mass % of phosphorus. 
   
   
       4 . The method for fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein the copper alloy further comprises 0.01 mass % to 0.1 mass % of boron. 
   
   
       5 . The method for fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein the copper alloy includes phosphorus and boron together in a range of 0.1 mass % or less. 
   
   
       6 . The method for fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein the indium included in the copper alloy is 0.1 mass % to 0.2 mass %. 
   
   
       7 . The method of fabricating soft copper alloy wire having flexure resistance and heat resistance, according to  claim 1 , wherein the annealing is conducted after the cold drawing, wherein an average crystal gain size after annealing is in a range from 2 μm to 20 μm.