US Patent 6918594 Face seal assembly with composite stator

A composite face seal has an annular seal rotor and an annular seal stator, both having a metal base portion and a radially extending flange. The flange has first and second axially facing surfaces. A first ceramic ring may be mounted to the first surface of the flange of either or both of the seal rotor and the seal stator by a first braze joint. A second ceramic ring may be mounted to the second surface of the flange of either or both of the seal rotor and the seal stator by a second braze joint. Each of the braze joints may include a molybdenum ring disposed between two braze rings or, for thicker seal assemblies, molybdenum and nickel rings disposed between braze rings.