Consideration of Wear at High Velocities C. S. Hale * , A. N. Palazotto † , and W. P. Baker ‡ Air Force Institute of Technology, Wright-Patterson AFB, OH 45433 The views expressed in this work are those of the authors and do not reflect the official policy or position of the United States Air Force, the Department of Defense, or the U.S. Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. This research is directed towards an understanding of the high speed interaction effects that two bodies have on each other. The experimental high-speed test track at Holloman AFB has undergone many design innovations over a span of fifty years. One of the problems that remain in the modern era related to improving the speed characteristics of a rocket test sled is the wear that the interconnecting device, called the slipper, undergoes as it slides down the rail. The research is separated into two main areas. The first is the metallurgical investigation in which the material change is brought about by the surface friction, and the second is the finite element analysis that attempts to capture the physics involved in the overall phenomenon. It became evident that the wear is not uniform but is dictated by the evolving aerodynamics of a sled moving at close to 1,500 m/s, the speed considered in this research, creating an uneven wear surface at the interface of the slipper and rail. The finite element analysis is separated into two models, one related to the global effects of movement using a predefined velocity versus time function, and the other depicted by a micro-local collision with a surface asperity. The Johnson-Cook failure criterion is incorporated in ABAQUS to arrive at the results. A method has been established which allows the prediction of wear for a time dependent forcing function obtained through a structural dynamics approach. Preliminary results indicate that the method is sufficiently robust that the physics of the wear process at high speeds is understood, and the physical results are reasonably well represented. Nomenclature P Pressure, Pa v Velocity, m/s F Force, N H Hardness, Pa A Slipper Area, m 2 k A Archard Wear Coefficient ˜ W Wear Rate, mm 3 /mm μ Coefficient of Friction I. Introduction I.A. Background The Holloman High Speed Test Track (HHSTT), located at Holloman AFB, NM, is a U.S. Air Force rocket- powered sled track facility used for investigating aircraft munitions and egress systems, hypersonic envi- ronments, and aerodynamic related effects. This includes testing of a variety of hypervelocity aerospace * Major, USAF, Ph.D. Candidate, Department of Aeronautics and Astronautics, AIAA Member. † Professor, Department of Aeronautics and Astronautics, AIAA Fellow. ‡ Associate Professor, Department of Mathematics and Statistics. 1 of 10 American Institute of Aeronautics and Astronautics 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference <br>17th 4 - 7 May 2009, Palm Springs, California AIAA 2009-2624 This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States.