鋳鋼の疲労強度に及ぼす欠陥の影響
1969 年 18 巻 191 号 p. 707-713
詳細
1969 年 18 巻 191 号 p. 707-713
A series of fatigue tests of steel were carried out, by alternating plane bending, twisting and rotating-bending, with the cast steel specimens which had been cut off from a cast-steel roll with a diameter of 1200mm. The results are discussed from a standpoint of an analysis of the effects of material-defects. The findings are as follows.
(1) The ratio of fatigue limit of alternating twisting and rotating-bending equals to 3/4. It is explained by the stress-concentration around a small blow-hole.
(2) The fatigue life is affected by the rate of material defects. The general S-N curve expresses the fatigue life of the specimens whose rate of defects equals in value to the mean value of the specimens used in the experiment. It is shown also that as far as the rate of defects becomes smaller in value, so far the fatigue life becomes longer.
