Preparation method of ceramic abradable sealing coating

The invention discloses a preparation method of a ceramic abradable sealing coating. The preparation method comprises the following steps: a ceramic bar is inserting into a modified ceramic bar flame spray gun; n a switch of the ceramic bar flame spray gun is turned on from 0 degree to 45 degrees, and the mixed gas is ignited at a nozzle position of the ceramic bar flame spray gun; and the ceramic bar flame spray gun is started to be in a 90-degree full-open state, after high-temperature and high-pressure similar supersonic speed flame flow beams sprayed by the ceramic bar flame spray gun are stable, bar melting particles are accelerated, and sealing coating spraying on the surface of the part is achieved. According to the method, the modified ceramic bar flame spray gun is utilized, the method is simple, operation is convenient, the use cost is low, application is very wide, and on-site maintenance operation can be carried out; and moreover, spraying materials are wide, almost all materials such as metal, ce