Preparation method for C/C composite material surface ZrC-SiC coating

A preparation method for a C/C composite material surface ZrC-SiC coating includes the steps of obtaining evenly-mixed Zr-Si-permeation promoter-slag former mixed powder after conducting vacuum ball milling, vacuum drying and sieving on Zr, Si, permeation promoter powder and slag former powder, dissolving PVA powder in ethyl alcohol to obtain a PVA alcoholic solution, forming Zr-Si-permeation promoter-slag former ceramic slurry after magnetic stirring is conducted on the Zr-Si-permeation promoter-slag former mixed powder and the PVA alcoholic solution, coating the surface of a C/C composite material matrix with the ceramic slurry, conducting high-temperature sintering and heat preservation, and then conducting furnace cooling. The surface of a large special-shaped component is coated with the ceramic slurry in situ, and therefore a Zr-Si coating can form an in-situ reaction layer on the surface of a C/C component; meanwhile, the abundant ceramic slurry can be quite easily stripped off a ceramic coating generated from the in-situ reaction, and engineering can be easily achieved on the surface of the large-size special-shaped C/C composite material component.