Abstract
Applicability of Manson’s rule to low cycle fatigue of cast steel containing small casting defects is examined taking account of the dependance of fatigue life upon tensile fracture strain.
Results are summarized as follows.
(1) Manson’s rule is applicable to the low cycle fatique of the defective cast steel, on the ground of the correlation between the increase in defectivity and the reduction in tensile fracture strain.
(2) Low cycle fatigue lives of the defective cast steels decrease with the increase of the total strain intensity factor range of initial defects.
(3) Low cycle fatigue life prediction of the defective cast steel using Paris’ rule based on the initial defect size corresponds well to the prediction using Manson’s rule based on defectivity.
