Anti-sintering dual-die composite structure thermal barrier coating and preparation technology thereof

Abstract

The invention discloses a preparation technology of an anti-sintering dual-die composite structure thermal barrier coating. The preparation technology includes the steps that first, metal is depositedon a substrate to form a metal bonding layer; second, first thermal barrier coating material powder and second thermal barrier coating material powder are deposited on the metal bonding layer in an alternative layered mode through a thermal spraying method to form a composite layered structure thermal barrier coating; and third, a plurality of longitudinal holes are formed in the composite layered structure thermal barrier coating through a strong flow impingement cooling pretreatment technology, and accordingly the dual-die composite structure thermal barrier coating can be obtained. According to the dual-die composite structure provided by the invention, the multiple holes perpendicular to the heat flow direction are spontaneously formed on service, high-strain tolerance is maintained and thus the characteristics of being resistant to sintering and long in service life are achieved.

Description

technical field [0001] The invention belongs to the technical field of coatings, in particular to a thermal barrier coating and a preparation process thereof. Background technique [0002] Thermal barrier coatings (TBC) are widely used in high-temperature hot-end components of aero-engines and gas turbines. As a heat-insulating ceramic coating, TBC with a thickness of 300-500 μm can increase the temperature-bearing capacity of the hot-end components by 50-300 °C, which is of great significance for increasing the gas inlet temperature, thereby improving the thrust-to-weight ratio and efficiency of the engine. . [0003] Thermal barrier coatings are generally prepared by thermal spraying, and their structure is formed by spreading and solidifying countless molten droplets. Therefore, the thermal sprayed thermal barrier coating usually exhibits a layered structure; micropores and microcracks of micron and submicron scale are also included in the layered structure. On the one...

AI Technical Summary

Problems solved by technology

However, during high-temperature heat exposure, micron and submicron pores within thermal sprayed coatings tend to heal due to sintering, which significantly reduces the thermal insulation capability of the coating

In addition, due to the sharp decrease in strain tolerance, the coating will accumulate a large amount of strain energy during service, which is one of the main reasons for the peeling failure of the coating.

Images