Thermal barrier coating with two bonding layers and preparation method of thermal barrier coating

Abstract

The invention discloses a thermal barrier coating with two bonding layers. The thermal barrier coating comprises a high-temperature alloy matrix, wherein a first bonding layer, a second bonding layer and a surface ceramic layer are deposited above the matrix in sequence; and the first bonding layer is of a multiporous laminated structure, and the second bonding layer is of a compact structure. A preparation method of the thermal barrier coating comprises the following steps: (1) grinding and performing sand blasting treatment on the surface of the high-temperature alloy matrix; (2) depositing a porous layer, which is the first bonding layer, with the porosity of 10 to 30 percent on the surface of the matrix by adopting gas shield protection plasma spraying; (3) depositing a compact layer, which is the second bonding layer, on the surface of the porous layer by adopting hypersonic flame spraying, low-pressure plasma spraying or cold spraying; and (4) depositing the surface ceramic layer on the surface of the second bonding layer by adopting atmospheric plasma spraying. The thermal barrier coating with the two bonding layers can both ensure that alpha-Al2O3 is continuously generated on the surfaces of the bonding layers and further relieve thermal expansion mismatch between the matrix and the ceramic layer, so that the service life of the thermal barrier coating is prolonged.

Description

technical field [0001] The invention belongs to the technical field of coatings, and in particular relates to a thermal barrier coating with a double-layer structure bonding layer and a preparation method thereof. Background technique [0002] Thermal barrier coating is a functional coating that coats high-melting-point materials with low thermal conductivity on the surface of high-temperature components for heat insulation. The temperature of the components can effectively improve the efficiency of the gas turbine. In recent years, the rapid development of plasma sprayed thermal barrier coatings has effectively improved the efficiency of gas turbines. However, the failure of thermal barrier coatings caused by the shedding of ceramic layers has seriously hindered the development and application of thermal barrier coatings. [0003] There are many factors affecting the life of thermal barrier coatings, among which the two most important factors are: TGO growth and the therma...

AI Technical Summary

Problems solved by technology

However, since the first adhesive layer is relatively dense, compared with the traditional single-layer adhesive layer, the ability of the adhesive layer with this structure to alleviate thermal expansion mismatch is not improved, that is, the ability of the adhesive layer to alleviate thermal expansion mismatch cannot be improved.

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