DETERIORATION OF ROLLING-CONTACT FATIGUE LIFE OF PEARLITIC RAIL STEELDUE TO DRY-WET ROLLING-SLIDING LINE CONTACT

This study is aimed at the deterioration of rolling contact fatigue (R CF) life of pearlitic rail steel, under rolling-sliding conditions, wh ere the wet phase of the test is preceded by different numbers of dry cycles. It is shown that initial dry cycles above a critical number ca uses sudden and significant deterioration in RCF life. This effect has been explained using the argument of plastic strain accumulation (rat chetting) in the surface layer during the dry phase when the coefficie nt of friction is above 0.25. A strong correlation was found between t he degree of ratchetting and the deterioration in RCF life. An empiric al relationship to estimate this deterioration was concluded.