Study on Nano-Oxide Powder Dispersed Ni-Electroplated Composites for Components Materials of NPPs

In this study, Ni composite layers embedding nano-oxide powders were electroplated on an alloy plate to mitigate and/or prevent various corrosion damages such as stress corrosion cracking, pitting, erosion-corrosion, etc.. Al₂O₃, TiO₂, Y₂O₃, and ZrO₂ nano-oxide powders were used to make Ni composite deposits in a sulfamate solution. After electrodeposition, their microstructures were examined using OM, SEM and TEM, and their mechanical properties were evaluated. According to the results, the amount of the co-deposited oxide powders in the composite increased regardless of the types of the nano-oxide, as the amount of oxide powder in the electrolyte bath increased. The hardness was measured to be relatively higher for the specimens produced in the electrolyte bath with higher concentrations of the nano-oxide powders and to decrease with increasing aging temperatures. even after aging at high temperatures. However, the behavior of the tensile properties was observed to be different with the different types of the oxide powders, possibly due to heavy agglomeration and inhomogeneous distribution of the oxide powders in the composites. Their corrosion properties can’t be presented this time, but they will be open at the next meeting.