COPPER ALLOY FOR ELECTRONIC AND ELECTRIC DEVICE, COPPER ALLOY THIN SHEET FOR ELECTRONIC AND ELECTRIC DEVICE, COMPONENT AND TERMINAL FOR ELECTRONIC AND ELECTRIC DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a copper alloy for electronic and electric device excellent surely and sufficiently in flexure processability, stress relaxation resistance and shear processability, and excellent in strength and conductivity.SOLUTION: A copper alloy for electronic and electric device has a composition containing Ni of 1.0 mass% to 5.0 mass%, Si of 0.1 mass% to 1.5 mass% and the balance Cu with inevitable impurities and having Ni/Si (mass ratio) in a range of 2.0 to 6.0, a crystal grain boundary set between measurement points having direction difference between neighboring measurement of over 15° by measuring measurement area of 1000 μmor more by EBSD method with measurement interval of 0.1 μm and analyzing it with excluding the measurement point having CI value analyzed by a data analysis soft OIM of 0.1 or less, special grain boundary ratio (Lσ/L) which is a ratio of the sum of each boundary length of Σ3, Σ9, Σ27a, Σ27b to all crystal grain boundary length of 10% or more and less than 60% and Vickers hardness of a surface of 120 or more.SELECTED DRAWING: None