COPPER ALLOY FOR TERMINAL, REDUCED IN CONTACT RESISTANCE AFTER STANDING AT HIGH TEMPERATURE

PROBLEM TO BE SOLVED: To obtain a copper alloy for terminal, capable of inhibiting an increase in contact resistance after standing at the service temp. of a terminal even if Sn plating is omitted, by adding proper amounts of Zn to a Cu-Fe-P alloy. SOLUTION: This copper alloy is an alloy consisting of, by weight, 0.05-0.5% Fe, 0.02-0.2% P, 0.1-5.0% Zn, and the balance Cu and reduced in contact resistance after standing at a temp. as high as 120-200 deg.C. Because Zn is preferentially oxidized at the time of standing at a temp. as high as 120-200 deg.C, the oxidation of Cu is controlled, and further, because the oxidizing rate of Zn is lower than that of Cu, the rate of growth of oxide film thickness is decreased and contact resistance is reduced. The effect of Zn is reduced when its content is lower than 0.1%, and, when it exceeds 5.0%, its effect is saturated and also reduction in electric conductivity and deterioration in stress corrosion cracking resistance are brought about.