Corrosion and wear resistant coating on zirconium alloy cladding
AssigneeWestinghouse Electric Corp.
InventorsPeng Xu, Lu Cai
Life of this patent
Estimating the term…
Abstract
The invention relates to compositions and methods for coating a zirconium alloy cladding of a fuel element for a nuclear water reactor. The composition includes a master alloy including one or more alloying elements selected from chromium, silicon and aluminum, a chemical activator and an inert filler. The alloying element(s) is deposited or are co-deposited on the cladding using a pack cementation process. When the coated zirconium alloy cladding is exposed to and contacted with water in a nuclear reactor, a protective oxide layer can form on the coated surface of the cladding.
Claims10
A method of coating a zirconium alloy substrate for use in a nuclear water reactor, comprising:
- obtaining the zirconium alloy substrate having a surface;
- combining a master alloy comprising one or more elements selected from the group consisting of chromium, silicon and aluminum, a chemical activator and an inert filler powder to form a coating mixture;
- obtaining a chamber having a heating zone and an inert or reducing gas atmosphere;
- surrounding the zirconium alloy substrate with the coating mixture in the chamber;
- heating the chamber to an elevated temperature;
- reacting the master alloy with the chemical activator to form a gaseous compound;
- diffusing the gaseous compound to contact the surface of the zirconium alloy substrate;
- decomposing the gaseous compound;
- depositing the one or more elements of the master alloy on the surface of the zirconium alloy substrate;
- and
- forming a substantially uniform diffusion coating layer thereon comprising zirconium and the one or more elements of the master alloy.
Dependencies are inferred from the claim text.