Reducing the fretting of metal surfaces subjected to friction - where lubricant contains metals forming a bearing eutectic on the surface

Process and means for the continuous formation of eutectic, metmetallic, surface solder, on metal surfaces subjected to frictional wear or fretting, by the electrochemical interchange of metal atoms, in which the lubricants used to reduce friction contain electrochemically effective metal cpds. in which the cations are more noble than the metal exposed to fretting. In the case of aq. lubricants or emulsions, water-soluble inorganic metal salts are pref. added, where the metal atoms are continuously interchanged with the metal subjected to fretting, possibly after decompsn. of the salts due to the pressure and temp. Alternatively, the lubricant can be an oil contg. soluble organic metal cpds. or complexes. The redn. of fretting corrosion, esp. where the metal exposed to friction is iron and the lubricant contains metal(s) which form a thin layer of "bearing metals" with the Fe. The tin layer of bearing metal or alloy flows readily by plastic deformation into the minute valleys on the fretting surfaces, forming a smooth surface with excellent bearing properties. Suitable metals forming the eutectic are e.g. Cu, Ni, or Zn-Cu-Pb.