The selection of the correct seal face materials is critical to the mechanical seal's performance. It might be said that the seal designer's material selection is the most crucial decision he or she will make.
Both the qualities of the individual materials and the combination of the tribological pair must be considered when considering materials for seal faces. Seal faces are often made of different materials. Although two "hard faces" are sometimes employed, these materials are commonly thought of as the "soft face" and the "hard face."
If the "ideal" seal face material could be discovered, mechanical seal design would be greatly simplified. The designer would not have to worry about the balancing ratio, face widths, or heat generation with such a material. Therefore there is a tremendous incentive to develop improved seal face materials.
Even though a perfect seal face material is not likely, the ideal face seal material can be described based on our experiences and problems with existing materials. This ideal material would have the following characteristics:
