Experimental evaluation of the local failure criterion and its implementation in a damage mechanics model

Abstract

Herein, a tensile test for notched round–bar specimens of two types of carbon steel used in nuclear containment vessels was performed. The test results were analyzed using the Bridgman solution and an elastoplastic finite element method. The analyses showed that ductile failures in the tensile state were initiated when the sum of equivalent and mean stresses reached a critical value of the material. A simple analysis of local failure for a nuclear containment was conducted using the failure criterion, and its engineering effectiveness was then discussed. The criterion is consistent with Argon's void nucleation model and can be implemented into the void nucleation term of stress control in the Gurson–Tvergaard (GT) model. The simulation performed using the GT model, which applied the limit value of the sum of equivalent and mean stress obtained from the tensile tests to the void nucleation term, successfully reproduced failure behaviors in the specimens.