M. Zheng et E. Niemi, ANALYSIS OF THE STRESS-CONCENTRATION FACTOR FOR A SHALLOW NOTCH BY THE SLIP-LINE FIELD METHOD, International journal of fatigue, 19(3), 1997, pp. 191-194
The relationships correlating the local stress and strain at the tip o
f a notch, the nominal stress expressed by the so called Neuber's rule
and Moski and Glinka's equivalent energy density method are studied f
or a shallow notch,using the slip-line field method proposed in plasti
c mechanics, and an elastic-plastic solution for the area close to the
notch. An elastic-perfect plastic material model is also used. It is
found that for lower stress amplitude Moski and Glinka's method is wit
h a good accuracy; however, the relative deviations of the actual stre
ss concentration factors calculated by these two methods to the theore
tical stress concentration factor are not small, even up to 20% for hi
gher stress amplitude as the size of the plastic zone around the notch
approaches the value of the radius of the notch curvature. While the
geometric mean of the two expressions mentioned above can be considere
d as a reasonable expression to correlate the local stress-strain and
the nominal stress, and thus the corresponding actual equivalent stres
s concentration factor can be evaluated, of which the relative deviati
ons to the theoretical stress concentration factor is shown to be <5%,
if the size of plastic zone close to the notch is not greater than th
e value of the radius of curvature of the notch. Copyright (C) 1997 El
sevier Science Limited.