Functionally Graded Nano-Composite for Gear Applications Navy STTR FY2005 Sol No.: Navy STTR FY2005 Topic No.: N05-T006 Topic Title: Functionally Graded Nano-Composite for Gear Applications Proposal No.: N054-006-0088 Firm: Technology Assessment & Transfer, Inc. 133 Defense Highway, Suite 212 Annapolis, Maryland 21401 Contact: Christopher Duston Phone: (410) 987-3435 Web Site: www.techassess.com Abstract: The U.S. Navy is seeking improved durability, increased life and reduced maintenance for aircraft, particularly rotorcraft, by increasing the hardness of gears and bushings. They have suggested that the incorporation of nano-sized materials to create a functionally graded surface may provide this advantage. Such a compositionally graded structure offers the tooth surface offers the high hardness required to impart surface durability under very demanding contact conditions; the subsurface case region provides the strength gradient; and the core region with low to medium hardness of HRC 35-40 (VHN 345-390) provides a substrate with high toughness. Technology Assessment, in association with the University of Delaware and SSI Technologies has proposed to form a functionally graded surface during gear manufacture. Benefits: A 20% improvement in gear endurance, generally considered achievable with coatings, would result in a cost avoidance of about $17 million/year to the DLA alone. Successful implementation of this project would result in substantial cost avoidances for the Navy. In the commercial gear sector, which is of the order of over $15 billion in the United States, similar improvements in performance have enormous fiscal implications. Return