Surface Engineering Technologies for Improved Gear Efficiency

The frictional losses in a gear mesh can be reduced by including super-finishing in the final manufacturing process. Phase I simulation tests of a hypoid rear axle gear shows a reduction in traction coefficient of 50 percent from an"as ground"surface to a high quality super-finished surface. This level of friction reduction is consistent for both low and high speeds. Phase I shows that costly super-finishing processes can be avoided with special oil formulations that polish surfaces while running. Gear steel heat treatment processing also affect polishing wear. Phase II proposes the development of a Run-In Polishing (RIP) oil formulation that can be used for existing fielded vehicles. A lapping process is also proposed that uses a Run-In Polishing (RIP) oil formulation as a final step in the manufacturing process. Optimization of the near-surface region through heat treatment is proposed to enhance the RIP process. Gear mesh simulation tests along with a physics and empirically based tribology model is proposed for gear design