Multi-element alloy coating, zirconium alloy cladding and fuel assembly

Abstract

A multi-element alloy coating, a zirconium alloy cladding, and a fuel assembly. The multi-element alloy coating comprises the following elements in percentage by mass: 65%-90% of Cr, 3%-13% of Al, 0.5%-8% of N, 5%-20% of Fe, and 1.5%-12% of Zr. The multi-element alloy coating can be applied to the zirconium alloy cladding, so that the problem of thermal expansion mismatch between the coating and a matrix is solved. The thermal stress is reduced. The hardness and the abrasion resistance performance of a conventional Cr coating are further promoted. By means of regulation and control of multi-element components, the anti-oxidation performance is enhanced, and the anti-oxidation protection effect of the coating under high-temperature steam environment of 1200°C is implemented.

Description

Technical field [0001] The invention relates to the technical field of nuclear fuels, in particular to a multi-element alloy coating, a zirconium alloy cladding and a fuel assembly. Background technique [0002] Under high temperature conditions, zirconium alloys are prone to heat production and hydrogen production reactions, which brings great safety hazards to nuclear reactors. At present, there are two main ways to improve the surface properties of zirconium alloys, thereby greatly improving the safety performance of nuclear fuel reactors: (1) Surface coating technology, through electroplating, electroless plating, thermal spraying, cold spraying, vapor deposition and other technologies in zirconium The alloy surface is covered with a layer of heterogeneous film. Through the close combination of the heterogeneous film and the matrix, the corrosion resistance of zirconium alloy under high temperature water vapor conditions can be significantly improved; (2) Surface modification...

AI Technical Summary

Problems solved by technology

[0003] At present, the main focus of zirconium alloy cladding is on corrosion, hydrogen absorption, wear resistance, etc. Among them, Cr-containing coatings have received extensive attention, but usually there is a large difference in the interface thermal expansion coefficient between the coating and the zirconium alloy substrate, resulting in the thermal shock. The undercoat and the zirconium alloy substrate generate thermal stress, which reduces the adhesion of the coating

Conventional metal coatings generally have the problems of low hardness and abrasiveness, and the eutectic reaction between the coating and the zirconium alloy substrate is prone to occur at high temperatures; although the Cr coating has good resistance to high-temperature steam oxidation, the oxidation resistance There is still room for further improvement