This research is concerned with the basic metallurgical mechanisms that affect sliding friction and wear of metals and alloys. Previous results have identified a sequence of events which include plastic deformation, local transfer, mechanical mixing and debris generation. These observations will be used to develop wear equations based on physical phenomena. Further research is proposed on the structure, composition and properties of the mechanically-mixed material generated by sliding. Some of this work will be performed in cooperation with W. D. Nix at Stanford University. In addition, the sliding behavior of semiconductor materials will be examined. Differences in deformation and fracture behavior of n- and p-type materials are expected to lead to differences in their friction and wear behavior.