Fatigue and deformation of notched specimens made of vanadium-based microalloyed steel

This paper is concerned with notch root deformation and fatigue behavior of a vanadium-based microalloyed (MA) steel. Fatigue tests were performed under constant load amplitude using circumferentially notched round and double-notched flat plate specimens with different stress concentration factors. Finite element analyses of the test specimens were conducted to obtain stress concentration factors and the degree of notch constraint. Notch strains were calculated by employing linear rule, Neuber rule, and strain energy density or Glinka rule. The results were compared with elastic-plastic finite element analyses. Experimental fatigue lives were compared with predicted fatigue lives using the strain-based approach. Among the three local strain rules, the local strain amplitudes calculated by Glinka rule correspond to more accurate predicted lives. Neuber rule resulted in over-conservative prediction of fatigue lives for notched round specimens.