Effects of boundary migration and pinning particles on intergranular oxidation revealed by 2D and 3D analytical electron microscopy

To evaluate the beneficial effects of intergranular carbides on inhibiting stress corrosion cracking (SCC), Alloy 600 samples in the thermally-treated (TT) and solution-annealed (SA) conditions were analyzed after exposure to 480 °C hydrogenated steam. Intergranular oxidation was observed in both samples, along with diffusion-induced grain boundary migration (DIGM). Compositional mapping revealed DIGM to be more severe in 600SA, while …