Fundamental study on applications of damage mechanics to evaluation of material degradation

Damage mechanics theory based on continuum mechanics has recently been attracting attention. This branch of physics describes the mechanical behavior of materials damaged through the production of microscopic voids. Nuclear structural components during operation seldom generate such voids. Damage mechanical theory may be of use for evaluating microscopic material behavior, and confirmation of this point was the purpose of this study. A comparison was made of calculation results, using constitutive equations of Chow and Wang, and of Lemaitre to describe ductile behavior of notched tension bars. The results were also compared with experimental results.