Amorphization and structural modification of the oxide film of Ni-based alloy by in-situ H charging in high temperature high pressure water environment

It is often assumed only limited amount of amorphous phase could generate in the oxide film of Ni-based alloy with H-participation. However, in this study, the formation of a remarkable amorphous layer on top of the oxide film of Ni-based Alloy 600 (Ni-15.5Cr-9.4Fe, wt.%) after oxidizing in high-temperature high-pressure water environment by in-situ H-charging condition is observed. A synergy of the film porosity and P-H2O/P-H2 is proposed as a plausible mechanism. Cavity layer appeared at the oxide and matrix interface, and the H-distribution are also discussed.