The main focus of this project is to investigate Intergranular Stress Corrosion Cracking (IGSCC) in Alloy 600 (Ni-based alloy) widely used in Pressurized Water Reactors (PWRs) and experimentally validate a predictive model. Predicting the long-term performance of nuclear reactors and maximising their operating time has been one of the major goals of the nuclear industry. Significant research and development efforts have been made to understand the factors affecting SCC, as it is one of the most significant cause of failures. Development of predictive models will reduce the expensive and time-consuming lab trials, test methods and more importantly shutting and restarting of power plants. High resolution Electron back scattered diffraction (HR-EBSD), transmission kikuchi diffraction (TKD) have been systematically used along with 3D-EBSD to evaluate the local stress concentration and geometrically necessary dislocation density (GNDs) along the grain boundaries. This project is sponsored by EDF and collaborates closely with the University of Manchester.