US Patent 7134939 Method for reducing wear of mechanically interacting surfaces

The invention is about reducing friction and wear and risk of seizure of mechanically interacting lubricated surfaces. A working surface of a mechanical piece engaged with another piece in relative sliding movement is processed for reduced friction. Two distinctly separate zones are allocated on the surface, one attractive to a lubricant used and the other repelling to the lubricant. The repellency may be conveyed to the repelling zone by either a mechanical modifying process or by a chemical change. In a preferred embodiment of the invention the repellency is obtained by lapping. The lubricant attractive layers are associated in a preferred embodiment of the invention with an assembly of recessed microstructures.