| 摘要 |
PROBLEM TO BE SOLVED: To provide a copper alloy having a high effect of reducing the warpage of a cooling plate even in the case Pb-free solder is used, having a high 0.2% proof stress and also having a high heat resisting temperature. SOLUTION: The copper alloy has a composition comprising, by mass, 0.8 to 20% Ni and 0.5 to 15% Ti, and the balance Cu with inevitable impurities, and in which the ratio of Ni/Ti is 0.9 to 5, and in which the average thermal expansion coefficient at 25 to 300°C is≤16.5×10<SP>-6</SP>/K. The copper alloy preferably has a thermal conductivity of≥150 W/(m×K), a 0.2% proof stress of≥350 N/mm<SP>2</SP>, and a heat resisting temperature of≥300°C. In addition to Ni and Ti, the copper alloy may comprise one or more kinds selected from B, C, Mg, Al, Si, P, Zn, Cr, Mn, Fe, Co, Sn, Zr and Ag in the range of≤0.5% in total. From the viewpoint of metallic structure, the copper alloy also comprising a Cu-Ni-Ti based compound phase by 4 to 75 vol.% is a suitable object. COPYRIGHT: (C)2006,JPO&NCIPI |
