| 摘要 |
PROBLEM TO BE SOLVED: To provide strength, electric conductivity, and excellent resistance to wear and heat, required of a contact material, by dispersing specific amounts of Cr into fiber state in a copper or copper-alloy matrix. SOLUTION: This copper alloy for contact material has a composition consisting of, by weight, 10-30% Cr and the balance copper with inevitable impurities, and further, Cr is dispersed into fiber state. If necessary, 0.005-0.5%, in total, of one or more elements among Al, Ni, Sn, Mn, Co, Ag, B, Mg, Ti, and Zr are further incorporated. Moreover, it is preferable to regulate the diameter of the dispersed fiber-like Cr to <=5μm. An ingot of this copper alloy is rolled and subjected to solution heat treatment, to aging treatment, and to cold working. By the last cold working mentioned above, crystallized Cr (partly Cr precipitate) is elongated into fiber state. By regulating the draft at the final cold working to >=90%, the diameter of Cr fiber can be regulated to <=5μm.
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