Reason Analysis on Defects in High-speed Railway Rail

A high-speed intercity railway was opened only about half a year, U71MnG 60 kg/m hot rolled rail was used in a station, the serious peeling defects were randomly appeared on the rail head tread of a line curve segment whose radius was 600 m at train terminal. By means of defect analysis, chemical composition analysis, tensile properties testing and metallographic examination, the reason of peeling defects was analyzed. The results showed that the peeling defects on rail head tread was caused by martensite on the surface layer, and martensite was due to serious friction between train wheels and rail.