A dimensionless fatigue life parameter
is developed for the correlation of fatigue data of carburized and core material. It is shown that the Smith-Watson-Topper parameter (E σ
max ɛ
a)
½ can be generalized to the form
to account for the fatigue strength differentials of dissimilar materials such as the core and case-core interface. Fatigue data generated using circumferentially notched specimens (K
t = 1.46 and K
t = 2.22) was successfully correlated to the core material fatigue data using this parameter at low stresses. From these observations, a scheme is proposed to predict low-stress fatigue life of a carburized member experiencing multiaxial stresses based on the core material fatigue response only.