One of the most important responsibilities for the engineer designing mechanical systems is the prediction of failure.  Although some (primarily static structures) are designed for infinite life, most moving mechanical systems must be designed for finite life.  Mechanical failures defining the “end of service life” for such systems can be grouped into 3 primary categories: strength and stiffness, fatigue and fracture, and wear and corrosion. 

The first two modes of failure have received much attention over the years, and numerous analytical and computational design tools exist which enable the design engineer to predict component life with reasonable accuracy and certainty.  Standardized testing methods have been established to measure relevant material constituent properties for inputs to these tools.  This is in stark contrast to the third category, wear and corrosion, where designers are relegated to subjective and heuristic methods to predict component life.  Unlike corrosion, where the experienced design has various methods of active surface protection such as cathodic protection using sacrificial anodes and/or controlled surface potentials, no tools are available to eliminate wear. The state of affairs is well summarized by the quote from a widely used engineering design handbook shown in the sidebar above.  The goal of this proposal is to establish theoretical bases, engineering design tools, and standard material property testing methods to enable accurate life prediction for systems where wear is the dominant failure mode; and to verify the correctness of the predictions using component level tests.