Preparation method of charcoal material surface gradient coating for resisting oxidation

Abstract

The present invention is preparation process of gradient oxidation resisting coating on the surface of carbon material. The preparation process includes the steps of: cleaning and stoving the surface of the carbon material; compounding slurring with silica powder, water and adhesive in certain weight proportion, and coating the slurry onto the surface of the carbon material through soaking, spraying or brushing; compounding silica powder, molybdenum powder, water and adhesive into slurry A of Mo / Si ratio 0.3-0.4, slurry B of Mo / Si ratio 0.8-1.2 and slurry C of Mo / Si ratio 1.8-2.3, and coating slurry A, slurry B and slurry C successively onto the surface of the carbon material through soaking, spraying or brushing; and sintering to obtain the product. The present invention has simple technological process, high production efficiency, good repeatability and low production cost and is suitable for industrial production.

Description

technical field

[0001] The invention belongs to the field of carbon material protection, and relates to a method for preparing a gradient high-temperature anti-oxidation coating on the surface of a carbon material. Background technique

[0002] Carbon materials have excellent heat resistance, chemical stability and electrical conductivity, and are widely used in high-temperature fields as structural and engineering materials. However, carbon materials begin to undergo oxidation reactions in an oxidizing atmosphere above 400°C, causing rapid deterioration of their physical and mechanical properties. Therefore, the oxidation protection treatment of carbon materials is to prolong their working life, improve their working stability and fundamental measure of reliability.

[0003] Coating treatment of carbon materials is a main method to solve the oxidation protection of carbon materials at high temperature (>1200°C). Silicon-based ceramic coatings such as (SiC, Si 3 N 4 )...