| 摘要 |
PROBLEM TO BE SOLVED: To provide a Cu-Co-Si copper alloy material which is superior in bendability, can acquire higher electro-conductivity, and is suitable for a material for electronic and electrical equipment such as a movable connector, and to provide a method for manufacturing the same.SOLUTION: The Cu-Co-Si alloy material includes 1.5-2.5 wt.% Co and 0.3-0.7 wt.% Si while controlling an element ratio of Co/Si to 3.5-5.0, contains secondary phase particles having diameters of 0.20 μm or more but less than 1.00 μm in the number of 3,000-150,000 pieces/mm, has grain sizes of 10 μm or smaller, has an electro-conductivity of 60% IACS or higher, and has an adequate bendability. The alloy material includes the secondary phase particles having diameters of 1.00-5.00 μm in the number of 10-1,000 pieces/mm, and may have a 0.2% yield strength of 600 MPa or more. The alloy material can be manufactured under conditions that a temperature of homogenization heating and heating for hot-rolling to be conducted after a casting step and before solution heat treatment is higher than a temperature of the following solution heat treatment by 45°C or higher, a cooling rate from a starting temperature of hot rolling to 600°C is 100°C/minute or lower, the temperature of the solution heat treatment is selected in the range of (50×Co wt.%+775)°C or higher but (50×Co wt.%+825)°C or lower, and aging treatment after the solution heat treatment is preferably carried out at 450-650°C for 1-20 hours. |
