Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 16, 2019 - September 18, 2019
Numerical simulation model was developed to simulate the competition between short-crack propagation and wear, and was applied to the rail head. The locations of crack initiation were given by a random generator in the ferrite regions at the beginning of the simulation. The crack was assumed to initiate when the total accumulated plastic shear strain in the region reached the critical shear strain value. The crack initiation at non-metallic inclusion was also considered. The two stage crack growth model proposed by Hobson was adopted as the short fatigue crack propagation. With regard to wear, the Archard model was adopted as the basis. The wear depth can be calculated from the normal pressure distribution in the wheel-rail contact region, the sliding velocities etc. The result of example simulation indicated that it was hard to achieve the ‘magic wear rate’ uniformly in the whole rail head by natural wear only of the single steel because the region of maximum wear rate and maximum crack propagation rate were generally different in the region.
