Bending Strength of Spur Gear Teeth : 1st Report, Cumulative Fatigue Damage of Normalized 0.45% Carbon Steel

Abstract

Bending fatigue tests of spur gear teeth made of normalized O.45% carbon steel (JIS S45C) are performed and several cumulative damage rules are examined taking account of the scatter of fatigue strength. The effect of the pattern of time variation of the tooth fillet stress is also investigated. Program loading tests with variation coefficients 1/12 and 1/9 indicate that Miner's rule is adaptable in time endurance region. The effect of the pattern of fillet stress on fatigue damage is observed in time endurance region, which cannot be explained by the count method such as peak method and full wave method.