Cu-Co-Si SYSTEM ALLOY FOR ELECTRONIC MATERIALS AND METHOD FOR MANUFACTURING SAME

Abstract

The present invention provides Cu—Co—Si system alloys that have desirable mechanical and electrical characteristics as a copper alloy for electronic materials, and have uniform mechanical characteristics. The copper alloys for electronic materials contain 0.5 to 4.0 mass % Co, 0.1 to 1.2 mass % Si, and the balance being Cu and unavoidable impurities. An average grain size is 15 to 30 μm and an average difference between maximum grain size and minimum grain size in every observation field of 0.5 mm 2 is not more than 10 μm.

1 . A copper alloy for electronic materials, containing 0.5 to 4.0 mass % Co, 0.1 to 1.2 mass % Si, the balance being Cu and unavoidable impurities, wherein an average grain size is 15 to 30 μm and an average difference between maximum grain size and minimum grain size in every observation field of 0.5 mm 2  is not more than 10 μm. 
     
     
         2 .- 5 . (canceled) 
     
     
         6 . A method for manufacturing the copper alloy according to  claim 1  or  9 , comprising sequentially conducting the following steps:
 step 1: casting an ingot having a desired composition; 
 step 2: heating the ingot for not less than 1 hour at 950° C. to 1050° C., thereafter hot rolling the ingot, setting the temperature to not less than 850° C. when hot rolling is completed, and cooling the ingot at an average cooling rate being not less than 15° C./s from 850° C. to 400° C.; 
 step 3: cold rolling the ingot at a reduction ratio being not less than 70%; 
 step 4: conducting aging of the cold-rolled material by heating at 350° C. to 500° C. for 1 to 24 hours; 
 step 5: conducting a solution treatment on the material at 950° C. to 1050° C., and cooling the material at an average cooling rate being not less than 15° C./s when the material temperature is reduced from 850° C. to 400° C.; 
 step 6: conducting optional cold rolling of the material; 
 step 7: conducting aging of the material; and 
 step 8: conducting optional cold rolling of the material. 
 
     
     
         7 . A copper alloy product comprising the copper alloy of  claim 1  or  9 . 
     
     
         8 . An electronic component comprising the copper alloy of  claim 1  or  9 . 
     
     
         9 . A copper alloy for electronic materials, containing 0.5 to 4.0 mass % Co, 0.1 to 1.2 mass % Si, the balance being Cu and unavoidable impurities, wherein an average grain size is 15 to 30 μm and an average difference between maximum grain size and minimum grain size in every observation field of 0.5 mm 2  is not more than 10 μm, the alloy meeting one or more composition conditions of (1) to (4):
 (1) Cr is furthermore contained in a maximum amount of 0.5 mass %; 
 (2) a single element or two or more elements selected from Mg, Mn, Ag and P are furthermore contained in total in a maximum amount of 0.5 mass %: 
 (3) one or two elements selected from Sn and Zn are furthermore contained in total in a maximum amount of 2.0 mass %; and 
 (4) a single element or two or more elements selected from As, Sb, Be, B, Ti, Zr, Al and Fe are furthermore contained in total in a maximum amount of 2.0 mass %.