A reaction bonded silicon carbide (RB-SiC) was joined with a new-type reaction-formed joint technology based on traditional reaction-formed joint process.The thickness,microstructure,and the mechanical and thermal properties of welding line were tested.The test results show that the welding line's thickness of RB-SiC in novel-formed joint technology is thin to 54～77 μm,and its microstructure is similar to the RB-SiC ceramic,so that mechanical property is excellent,the average bending strength of 10 joints is 307 MPa.The welding line doesn' influence on the surface figure before and after the temperature of the joining blank changes from-10 ℃ to 65 ℃,which shows the thermal property of welding line is suitable for that of RB-SiC ceramic.