摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method, device, and system for estimating the relative superiority of internally originated flaking life of rolling contact metal material, capable of estimating the relative superiority of internally originated flaking life of metal material such as rolling bearing steel having high shear fatigue strength from torsional fatigue test results for a short period. <P>SOLUTION: A method for estimating relative superiority includes a step of testing (S1), a step of determining shear fatigue life (S2), and a step of estimating relative superiority (S3). In the step of testing (S1), the relation between shear stress amplitude and load frequency for a metal material is obtained from an ultrasonic torsional fatigue test. In the step of determining shear fatigue life (S2), the shear fatigue life in a time strength region is determined from the relation between shear stress amplitude and load frequency. In the step of estimating relative superiority (S3), the metal material which is superior in the determined shear fatigue life is estimated to be superior in the relative superiority of internally originated flaking life. <P>COPYRIGHT: (C)2013,JPO&INPIT |