Abstract
It was clarified in the previous report that the internal strain could easily and sensitively be detected by using inverse Wiedemann effect and that the change of the internal strain along with the process of the fatigue could slso be detected. In this report the change of the internal strain of the torsionally worked specimen caused by the repeated loading was measured by this method. The Schenbk-type’s torsion fatigue tester was used. The experimental apparatus used was the same as in the previous report. The results are briefly summarized as follows: (1) Intensity of induced current is always low at the early stage of the fatigue regardless of the applied load. And the heavier load in, the greater the degree of the lowering value is. I think that the lowering of the value is due to the relief of the torsional internal stress but the established facts cannot be discussed only from the experimental results which have been made clear here. (2) Increase of induced current is generally recognized before the fatigue failure. And the phenomenon of moving up and down of the current density with the process of the fatigue is not recognized in the present case, while the case of the non worked specimen is characteised by the fluctuation of the value. (3) In the case of load less than the fatigue limit the lowering of intensity is also recognized. But the degree of lowering is small and the induced current soon reaches the stationary value. The heavier load is, the larger the number of repeated cycles needed for saturation of induced current is. (4) When the fatigue limit is raised and the slope of the wohle curve becomes solw in the case of the worked specimen.
