Silicon carbide seal faces have the property of excellent resistant-corrosion, high mechanical strength, high thermal conductivity and good self-lubrication. Silicon carbide seal faces are widely used in many different industries, including spacecraft, machinery, metallurgy, printing and dyeing, foodstuff, pharmaceutical, auto industry and so on. When the silicon carbide seal faces are combined with graphite faces, the friction is the smallest, they can be made into mechanical seals which are able to work in highest working requirements.