小穴をもつS45C焼なまし材の疲労限度に及ぼす油環境の影響

抄録

Rotating bending fatigue tests were carried out on specimens with a small blind hole of annealed 0.42% C steel in air and in oil. Although the fatigue strength at a stress level above the fatigue limit in oil is higher than that in air, the fatigue limit is roughly equal in both environments. This phenomenon is explained from the fact that an oil environment has two effects on crack growth due to the exclusion of moisture and oxygen which oppose each other, that is, the suppression of corrosion and fretting oxide.