We investigated the effects of mean tensile stress and bending strain waveform on fatigue life of hard-drawn copper contact wire, and verified that fatigue properties under different mean tensile stresses can be arranged uniformly by {(maximum stress)*(stress amplitude)}1/2 of fatigue process. The effect of smaller amplitude components in substantial strain waveform on fatigue breakdown of contact wire is less; therefore, the possibility of fatigue breakdown may be estimated by the peak value of the strain waveform. When examined some case studies regarding the effect of oscillating frequency on fatigue life as referenced to the effect of steepness of strain waveform, the fatigue life becomes longer in a higher frequency. On the other hand, in carrying out fatigue tests with several waveforms including a steep one, there was no significant difference in the fatigue life between the waveforms. It is conceivable that the steep waveform reduces the fatigue life is little by these results.

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