Analysis on Corner Fine Cracks and Scaling Defects of U75V Rail

Corner fine cracks and scaling defects could be found on the U75V rail after being used in the curve segment for a period of time.The reason for defects was analyzed by means of chemical analysis,mechanical testing,metallurgical testing and scanning electron microscope.The results showed that the damage was nothing to do with the quality of rail,corner fine cracks and scaling defects were caused by rolling contact fatigue under high contact stress.Such damage could be prevented by optimizing wheel/rail profile,setting up appropriate deficient super elevation,grinding and oiled in time,and selecting reasonable rails.