Thermal structure composite material long-service-life composite coating and preparation method thereof

The present invention relates to a thermal structure composite material long-service-life composite coating and a preparation method thereof. The preparation method comprises: carrying out thermal insulation on a thermal structure composite material for a first preset time at a first preset temperature, carrying out pre-oxidation, and naturally cooling the thermal structure composite material to a room temperature; under a protection atmosphere, embedding the thermal structure composite material into a first embedding powder material, and carrying out thermal insulation for a second preset time at a second preset temperature to obtain a thermal structure composite material having a SiC coating; and embedding the thermal structure composite material having the SiC coating into a second embedding powder material, placing in a protection atmosphere, heating at a preset heating rate to achieve a third preset temperature, and carrying out for a third preset time. According to the present invention, with the prepar