FRACTURE TOUGHNESS NUMERICAL MODELLING OF THE MARTENSITIC CHROMIUM STEEL

To evaluate the resistance to failure of the constructions with cracks usually the fracture criterions are used. One of such criterion used to evaluate failure is J-integral. Calculated value of failure criteria in construction with crack is compared with its critical value for the material the construction is made of. The values of Jintegral for the materials are usually experimentally determined. This article presents the methodology for the determination of J-integral using numerical methods. For this purpose the Finite Element (FE) code ABAQUS was used. The modelling of the J-integral of steel P91 was performed. 2D and 3D FE models were used for this purpose. The experimental stress - strain curve was used as material description. For crack growth calculation the crack opening displacement as a function of crack length is presented. The prognosis results of J-integral were compared with experiment data. As results of investigation the J-integral of steel P91 was determined. Prognosis results were compared with experiment. Numerically determined J-integral has acceptable coincidence with experiment results.