Loading frequency effect on the fatigue endurance of structural carbon steels: Estimation based on dislocation motion theory and experimental verification of the model

Based on a previous model dedicated to the prediction of the loading frequency effect on the fatigue endurance of low-carbon steels, the present work elaborates a strategy to extend its application range to medium- and high-carbon steels. From this viewpoint, fatigue tests were newly performed for JIS S45C (0.42%C) steel. Thereafter, the model effectiveness has been discussed on the basis of numerous data reported by other researchers, resulting in an overall correlation coefficient of 0.940. Finally, the model outcomes derived from a dislocation energy viewpoint have presented a good agreement with the experimental trend.