Seeing the third-body formation of metallic tribosystems by novel on-line tribometry

During lubricated sliding of metallic surfaces the near surfaces undergo significant changes in terms of topography, composition and microstructure [1] and a so-called “third body” [2] develops. The third-body formation strongly influences the frictional and wear behavior of the system. A system that develops a nanocrystalline microstructure which is chemically different from the bulk material can provide low friction and wear after the running-in. Also the surface topography typically develops a roughness that is in the same order of magnitude as the grain size