Experimental and numerical investigations of the critical values of J-integral for the steel of steam pipelines

Abstract Steel grade 14MoV6-3 is a low-carbon microalloyed steel with addition of chromium and molybdenum. This grade is designed mainly for power industry applications, withstanding operating at elevated temperatures. In this paper, mechanical properties of steel grade 14MoV6-3 and methodology of calculation of critical values of the J -integral are presented. The level of damage is determined by analyzing the virgin material of the same grade. The focus of presented investigation is on the experimental J-integral determination, where critical values of the J-integral (J IC ) are compared with the values obtained by using the finite element methods (FEM). FEM model was defined on the basis of experimental conditions and obtained numerical values should confirm our experimental results.