抄録
The effects of degree of reduction by cold-drawing and annealing temperature on the fatigue strength were studied for 10% and 30% cupro nickel alloys at 107 cycles on rotating-beam fatigue tester. The corrosion-fatigue properties for tough pitch copper, 10%, 20% and 30% cupro nickel alloys in 3% NaCl aq. solution at 108 cycles were also studied.
The following results were obtained;
(1) The fatigue strength of 10% cupro nickel alloy increases with the degree of reduction by cold-drawing. In the case of 30% cupro nickel alloy, the fatigue strength increases with the degree of reduction up to 30% by cold-drawing and then decreases with further reduction.
(2) The fatigue strength of annealed specimen depends upon the average grain size, and the specimen of larger grain size shows smaller fatigue strength.
(3) The corrosion-fatigue strength obtained in 3% NaCl aq. solution increases with Ni content. The effects of cold-working and annealing treatment on the fatigue strength oftained in 3% NaCl aq. solution are not so remarkable as those in air. Those results were summarized in Fig 12.
