| 摘要 |
PROBLEM TO BE SOLVED: To provide a copper alloy plate material which has reduced anisotropy while maintaining its high strength satisfying 0.2% proof stress of≥900 MPa, and simultaneously has excellent bendability and stress relaxation resistance, and to provide a method for producing the same. SOLUTION: The copper alloy plate material is composed of a copper alloy having a composition containing, by mass, 0.8 to 3.5% Ni, 0.3 to 2.0% Si and 0.5 to 2.0% Co, further containing one or more kinds selected from among Fe, Cr, Mn, Ti, V and Zr in an amount of≤2.0% in total, wherein the total of one or more kinds selected from among Fe, Cr, Mn, Ti, V and Zr in addition to Co is defined as X, an X/Ni mass ratio is 0.3 to 1.5 and an (Ni+X)/Si mass ratio is 3 to 6, and the balance Cu with inevitable impurities. The copper alloy has precipitates satisfying numerical expression 1: (N<SB>N</SB>+N<SB>X</SB>)/N≥0.8 and numerical expression 2: ¾d<SB>N</SB>-d<SB>X</SB>¾/d<SB>N</SB>≤0.3, has crystal orientation satisfying numerical expression 3; Iä200}I<SB>0</SB>ä200}≥0.5, and has an in-crystal grain twin crystal density satisfying numerical expression 4; N<SB>G</SB>=(D-D<SB>T</SB>)/D<SB>T</SB>≥0.5. The method for producing the copper alloy plate material is also provided. COPYRIGHT: (C)2011,JPO&INPIT |
