Silicon carbide ceramic connecting piece as well as preparation method and application thereof

The invention belongs to the technical field of ceramic welding, and discloses a silicon carbide connecting piece and a preparation method and application thereof, and the method comprises the following steps: mixing SiC, Si3N4 and glass powder CAMZS to prepare a welding flux; the two silicon carbide to-be-welded areas are coated with welding flux, and a to-be-connected assembly is obtained; the method comprises the following steps: putting a to-be-connected assembly into a heating furnace, mechanically pressurizing the to-be-connected assembly in a nitrogen atmosphere, welding at 1500-1650 DEG C, and cooling to obtain the silicon carbide connecting piece. The thickness of a connecting layer of the connecting piece is 10-60 microns, the shear strength of the connecting piece at the room temperature is 60-100 MPa, the shear strength of the connecting piece at the 1000 DEG C inert atmosphere is 70-110 MPa, the shear strength of the connecting layer at the room temperature after three times of 800 DEG C water qu