Surface texture and processing method of a thermal barrier coating

Abstract

The invention provides a surface texture of a thermal barrier coating and a processing method thereof. The interface between the substrate and the coating is used as a textured surface, or the plane located at the interface that is offset toward the inside of the coating is used as a surface texture. A textured surface, on which a number of irregular shapes are regularly distributed. The interface between the substrate and the coating is specifically the interface between the substrate and the bonding layer or the interface between the bonding layer and the functional coating. The invention uses multiple laser composite processing technologies to process regularly distributed irregular shapes on the texture surface, so as to achieve the effects of strong bonding of the coating, optimizing the internal stress of the coating, and inhibiting the expansion of cracks.

Description

technical field [0001] The invention relates to the field of surface engineering, in particular to a surface texture of a thermal barrier coating and a processing method thereof. Background technique [0002] At present, the technologies for preparing thermal barrier coatings mainly include plasma spraying, electron beam-physical vapor deposition, high-velocity flame spraying technology and laser cladding. Among them, plasma spraying has the advantages of mature technology and high deposition efficiency. The prepared thermal barrier coating has a "fish scale" layered structure, but it has a poor mechanical bond with the substrate. The thermal mismatch between the junction layer and the functional coating is easy to peel off during use, affecting the overall lifespan. [0003] The Chinese patent discloses a coating preparation method to improve the bonding force between the thermal barrier coating and the substrate. The industrial NiCrAlY composite powder is used as the bott...

AI Technical Summary

Problems solved by technology

This technical solution uses the micro-pit array on the surface of the substrate as the mechanical anchor point between the coating and the substrate. Although it can improve the bonding force between the coating and the substrate to a certain extent, the diameter of the spot used is 22 μm, and the prepared micro The pore depth is 30-50 μm, which is a deep micropore with a small diameter. The micropore structure is not conducive to the entry of coating particles, and pore defects are prone to occur. Morphological quality, but the slag defects on the edge of the micropore and the inner wall will cause the crack source inside the coating, which is easy to cause the coating to peel off; moreover, the copy performance of the adopted morphology is poor, which affects the bonding between the substrate and the bonding layer. The force has an optimized effect, but it cannot effectively solve the problem of poor bonding between the adhesive layer and the functional coating

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