CU-CO-SI-BASED COPPER ALLOY FOR ELECTRONIC MATERIAL, AND PROCESS FOR PRODUCTION THEREOF

摘要

Disclosed is a Cu-Co-Si-based copper alloy having high levels of strength and conductivity and also having excellent sag resistance. Specifically disclosed is a copper alloy for an electronic material, which comprises 0.5 to 3.0 mass% of Co, 0.1 to 1.0 mass% of Si, and a remainder made up by Cu and unavoidable impurities, wherein a part of second phase particles precipitated in the mother phase which have particle diameters of 5 to 50 nm inclusive are present at a density of 1×1012 to 1×1014 particles/mm3, a part of the precipitated second phase particles which have particle diameters of not less than 5 nm and less than 10 nm are present at a density that is 3 to 6 times relative to the density of the precipitated second phase particles having particle diameters of 10 to 50 nm inclusive.