SOLID LUBRICANTS FOR AERONAUTICS AND SPACE APPLICATIONS

THE INNOVATION WE PROPOSE IS THE USE OF IMPROVED CUBIC BORONNITRIDE (CBN) THIN FILMS AS SOLID LUBRICANTS FOR LONG-TERM NASA SPACE MISSIONS. THE IMPROVED FILMS ARE DEPOSITS USING THE NOVEL TECHNIQUE OF LASER ABLATION. THE BENEFIT TO NASA IS A NEW SOLID LUBRICANT FILM WITH SIGNIFICANTLY GREATER ATOMIC OXYGEN RESISTANCE AND LONGER LIFE THAN CURRENTLY AVAILABLE IN COMMERCIAL PRODUCTS. CBN EXHIBITS EXCEPTIONAL DURABILITY, HARDNESS SECOND ONLY TODIAMOND, ULTRAHIGH RESISTANCE TO WEAR AND RELATIVELY LOW COEFFICIENT OF FRICTION. ITS RESISTANCE TO ATTACK BY ATOMICOXYGEN SHOULD BE BETTER THAN DIAMOND. IN ADDITION, CBN THINFILMS CAN BE DEPOSITED AT TEMPERATURES SIGNIFICANTLY LOWER THAN DIAMOND FILMS AND ON A GREATER VARIETY OF SUBSTRATES. THIS UNIQUE COMBINATION OF PROPERTIES MAKES CBN A PRIME CANDIDATE FOR USE AS A SOLID LUBRICANT IN LONG-TERM SPACE APPLICATIONS. IN PHASE I, FOSTER-MILLER WILL DEMONSTRATE THE EFFECTIVENESSOF CBN AS A SOLID LUBRICANT FOR NASA SPACE APPLICATIONS. COMMERCIALLY AVAILABLE, POLYCRYSTALLINE CBN (PCBN) WILL BE CHARACTERIZED IN TERMS OF ITS TRIBIOLOGICAL PROPERTIES IN THE AS-RECEIVED CONDITION AND AFTER BEING SUBJECTED TO ATOMIC OXYGEN EXPOSURE. SIMULTANEOUSLY, PCBN THIN FILMS WILL BE FABRICATED BY LASER ABLATION AND THEIR PERFORMANCE COMPARED TO BULK PCBN AND COMMERCIALLY AVAILABLE (NON-LASER ABLATED) PCBN FILMS.