| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for estimating the fatigue limit surface pressure of a rolling bearing material for an airplane capable of precisely estimating the fatigue limit surface pressure of the rolling contact metal material such as rolling bearing steel or the like from the result of a short-term fatigue test.SOLUTION: The relation between the shearing stress amplitude and load frequency of a metal material is calculated by a perfect alternating ultrasonic twist fatigue test (S1) and the shearing fatigue strength τin an ultralong life region is determined from the relation between the shearing stress amplitude and load frequency of the metal material according to an S-N diagram or the like (S2). The maximum contact surface pressure Pat the time of action of the load, wherein the maximum alternate shearing stress amplitude τacting on the inside of the surface layer of the metal material determined from contact dimension data and the load becomes equal to the shearing fatigue strength τ, is set as the estimate value of fatigue limit surface pressure P(S3). |
