PURPOSE: To manufacture an electric contact material which has strong spring property and is hard to buckle by underplating a specified base material with Ni in a specified thickness, drawing the base material after it is plated with Au in a specified thickness, and heat-treating it.
CONSTITUTION: A base material 1 consists of 30-40wt.% of Co, 10-20wt.% of Ni, 10-20wt.% of Cr, 2-10wt.% of W, 2-10wt.% of Mo, ≤1wt.% of Ti, ≤1wt.% of Mn, ≤1wt.% of Si, and the rest Fe. A Ni film 2 with 0-10μm of plating thickness is formed on the base material 1 as an undercoating, and after a Au film 3 with 0-10μm of plating thickness is formed by plating Au, the base material is drawn and heated at 400-800°C. In this way, mechanical strength, for example, tensile strength and transverse rupture coefficient of the obtained base material become as high as 180-220kg/mm2 and 7800-8300kg/mm2, respectively and thus an electric contact material having strong spring property and being hard to buckle can be obtained.
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