Method for coating a metal crucible element with a mixture of glass and ceramic
AssigneeAreva Nc
InventorsPatrice Brun, Geoffroy Berard, Jacques Lacombe
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Abstract
Angular sectors of a cylindrical wall of a crucible for vitrification of waste, built in steel and subject to high temperatures, are coated with a mixture of mainly glass and ceramic, the coating being subject to a heat treatment comprising a step between 650° C. and 850° C. so as to perform surface melting of the mixture filling the open porosity, improving dielectric strength and the cohesion of the coating, but without producing any excessive thermal expansion or oxidation of the substrate which would lead to fast flaking of the coating.
Claims8
A method for coating steel sectors of a vitrification crucible, characterized in that it consists of applying a mixture of glass and ceramic by projection via a plasma on the steel of the sectors, and of subjecting the obtained coating to a heat treatment, the mixture having a mass composition of 50% to 70% of glass having a glassy transition temperature below 650° C., and of 30% to 50% of ceramic, and the heat treatment being conducted at a maximum temperature which is greater than a pour temperature of the mixture, and comprised between 650° C. and 850° C.
Dependencies are inferred from the claim text.