Hf-Ta-Mo-Si multi-element ultra-high-temperature anti-oxidation coating and preparation method thereof

The invention discloses an Hf-Ta-Mo-Si multi-element ultra-high-temperature anti-oxidation coating which is composed of an Hf-rich surface layer, a TaSi2 middle layer and a Ta5Si3 interface reaction bottom layer, and the interface between the layers is an in-situ synthesis interface. The preparation method of the coating comprises the following steps: 1, pretreating the surface of the tantalum alloy; 2, ball-milling and uniformly mixing hafnium powder, molybdenum powder, silicon powder and a dispersing agent to obtain composite suspension slurry; and thirdly, the composite suspension slurry is pre-placed on the surface of the tantalum alloy subjected to surface pretreatment to be dried and subjected to high-temperature fusion sintering. The coating provided by the invention has better high-temperature stability and excellent thermal scouring resistance and thermal shock resistance, and provides effective protection for a tantalum alloy material under the oxygen strong thermal shock condition at 1000-1900 DEG