Novel thermal barrier coating

Abstract

The invention discloses a novel thermal barrier coating which is a composite coating with a performance of change of gradient. The thickness and the component ratio of the composite coating change from outside to inside, the thermal barrier coating mainly comprises a metal bonding layer and a ceramic layer which are formed on a base material surface by utilizing a staggered laminating structure, the thickness of the ceramic layer decreases from outside to inside, and the component ratio of the metal bonding layer changes from outside to inside. According to the novel thermal barrier coating, a multilayer staggered structure is adopted by the metal bonding layer and the ceramic layer of the coating, the thickness and the component ratio of the coating are arranged more reasonably, so that the thermal coefficient of expansion inside the coating tends to be mild, and the coating is provided with a superior thermal shock resistance and an antioxidant capacity; and simultaneously, the preparation process of the coating is convenient to implement, the performance of the coating is easy to control, the cost is moderate, and the practical performance is superior.

Description

technical field [0001] The invention relates to a thermal barrier coating, in particular to a novel thermal barrier coating with gradient performance, belonging to the technical field of metal coatings. Background technique [0002] In recent years, with the development of aero-engines towards high flow ratio, high thrust-to-weight ratio and high turbine inlet temperature, the gas temperature and gas pressure in the engine combustion chamber have been continuously increasing. When the thrust-to-weight ratio of the engine reaches 20, the gas inlet temperature will exceed 2000°C. This temperature has exceeded the temperature that the nickel-based superalloys used to manufacture turbine blades and guide vanes can withstand. Even if intermetallic compound materials and directional solidification technology are used unbearable. The cooling effect of compressed air on the blades is limited, and the cooling technology inevitably loses a large part of heat while reducing the temper...

AI Technical Summary

Problems solved by technology

[0003] The thermal barrier coating is mainly composed of a metal bonding layer and a ceramic layer. The preparation process of the double-layer structure is simple and the heat insulation ability is strong. It is the most widely used form at present; however, the interface between the metal bonding layer and the ceramic layer in the double-layer structure Obviously, the thermal expansion coefficient jumps greatly at the interface, and under the action of thermal load, a large stress will be generated inside the coating, which makes it difficult to improve the thermal shock resistance of the coating; and the thermal shock resistance of the current multi-layer or gradient system structure Barrier coating has the high-temperature performance of ideal coating design, and its thermal shock resistance is better than that of double-layer coating, but the preparation technology is more complicated and the cost is higher, and it still needs further improvement

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