CU-NI-SI-BASED ALLOY FOR ELECTRONIC MATERIAL

摘要

Disclosed is a Corson alloy having dramatically improved properties (e.g., high strength and high conductivity) which are achieved by allowing the effect of the addition of Cr to a Cu-Ni-Si-based alloy to exhibit more effectively. Specifically disclosed is a copper alloy for an electronic material, which comprises 1.0 to 4.5 mass% of Ni, 0.50 to 1.2 mass% of Si, 0.0030 to 0.3 mass% of Cr (provided that the weight-based ratio of Ni to Si (i.e., a Ni/Si ratio) by weight is as follows: 3 = Ni/Si = 5.5), with the remainder being Cu and unavoidable impurities. In the copper alloy, a Cr-Si compound having a size of 0.1 to 5 µm (inclusive) is dispersed in the material at a dispersion density of 1 × 10⁶ particles/mm² or less, wherein the atom-based ratio of the concentration of Cr to that of Si in the dispersed particle is 1 to 5.