DEVELOPMENT OF A MODEL FOR THE CRACK INITIATION AND GROWTH SIMULATION OF THE STRUCTURAL MATERIALS UNDER LIQUID METAL EMBRITTLEMENT CONDITIONS

Abstract

The paper develops a model based on the finite element analysis of the crack initiation and propagation in the generation IV structural materials due to the liquid metal embrittlement (LME) phenomenon. The stress-strain experimental curves obtained at 400 ºC by testing in the liquid lead and air were converted as the Ramberg - Osgood constitutive equations by proposing a new method to obtain the strain hardening coefficient. To estimate the accuracy of prediction are used the residual and standardised residual in the context of regression analysis. Further, a model based on the Gurson–Tvergaard-Needleman approach (GTN) was set up to evaluate the crack initiation and propagation under the LME conditions. An application of the developed micro-mechanical model that predicts the crack initiation and propagation in the Compact –Tension (CT) specimen due to LME is performed. The model is practical in the structural integrity activities framework of the structural materials that will be used in the ALFRED demonstrator, which will be build-up at RATEN ICN, Romania.