Zirconium-based material surface in-situ ceramization composite treatment method

Abstract

The invention discloses a zirconium-based material surface in-situ ceramization composite treatment method. The method comprises the following steps: 1, detecting Fe pollution in a surface nanocrystallization treatment environment; 2, pretreating the surface of a zirconium-based material; 3, carrying out surface nanocrystallization treatment on the zirconium-based material; 4, detecting Fe pollution of the zirconium-based material subjected to nanocrystallization treatment; 5, detecting Fe pollution in a heating equipment environment; and 6, performing high-temperature ceramic treatment. The smooth and uniform zirconium-based material processing surface is obtained through nanocrystallization treatment, the stress distribution state of the surface of the zirconium-based material is improved, grain refinement of the surface of the zirconium-based material is promoted, then a complete and compact in-situ ceramic composite treatment layer is formed in combination with high-temperature ceramic treatment, the corrosion resistance and the wear resistance of the surface of the zirconium-based material are improved, the comprehensive service performance of the metal material is greatly improved, and structural function integration of the metal material is effectively achieved.

Description

technical field [0001] The invention belongs to the technical field of surface modification of metal materials, and in particular relates to an in-situ ceramic composite treatment method for the surface of zirconium-based materials. Background technique [0002] Zirconium alloys have the advantages of small thermal neutron absorption cross-section, good radiation stability, and good corrosion resistance in high-temperature water. They are widely used as fuel cladding materials and core structural materials, and are key materials for water-cooled reactor nuclear power plants. During service, the zirconium alloy reacts with high-temperature and high-pressure water, resulting in the formation of an uneven boil-like corroded, white, loose and easy-to-fall oxide film on the surface of the fuel element cladding, resulting in premature damage to the fuel element and seriously affecting its service life. The development of new zirconium alloys also requires a long test and verificat...

AI Technical Summary

Problems solved by technology

Among them, the direct shot-peening nano-treatment on the surface of zirconium alloy is limited by the characteristics of the metal substrate itself. When the surface composition of the material does not change, the nano-layer formed on the surface does not have the ability to completely resist environmental effects and some Special surface functional properties, and lack of engineering service verification guidance and valuable quantitative optimization process data lead to relatively large roughness and local micro-area damage on the zirconium alloy surface, which easily induces stress concentration, stress corrosion cracking and pitting corrosion hidden dangers; At the same time, the nano-layer does not significantly improve the surface hardness of the rare metal zirconium alloy, which cannot meet the long-term use requirements

Since the welds on the inner and outer surfaces of zirconium alloy equipment are distributed in different positions, the surface conditions of each position are very different. When directly performing high-temperature ceramic treatment on the surface of zirconium alloy, it is necessary to perform mechanical grinding and polishing on the inner and outer surfaces of the equipment, which is easy to introduce impurities. Elements are difficult to operate in engineering, and the workload is large and the labor intensity is high. The key is that the color uniformity, compactness, bonding strength, abrasion resistance and fatigue resistance of the surface ceramic film layer are too different and unstable. , it is difficult to promote in engineering applications, and the quality of ceramicization cannot be guaranteed. If the surface pretreatment is carried out, the pickling process will be increased, causing environmental pollution. At the same time, waste acid treatment is also a big problem, resulting in an increase in cost. Or ban the pickling process

[0005] So far, there is no report on the research or engineering application of zirconium-based materials to improve the comprehensive performance of ceramic layers through the surface nanometerization-high temperature ceramicization composite process

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