White etching layer (WEL) occurs on rail surface layer due to wheel-spin or wheel sliding of train wheels, and the WEL often cause cracks. Normally, ultrasonic test takes place for detecting such cracks. However, concerning the WEL itself, any effective method of detecting has yet been developed as of present. If it is possible to detect WEL, it is contributing to management of the life cycle of rails. In this study, we have continued the examination of Non-Destructive Test (NDT) by SQUID (Superconducting Quantum Interference Device). We report that we succeeded in detecting the layer (thickness of 5μm) with a specimen, which simulated the WEL developed by us.

Copyright (c) 2007 Railway Technical Research Institute