Research on the Relationship between Average Friction Coefficient and Contact Press in Metal Plastic Forming

In the process of metal material reciprocal rubbing,friction coefficient no longer corresponds to Coulomb theory with the increase of contact press on material surface.It is not only related to the characteristics of surface in contact,surface topography and lubricating state,but also to contact press.With the increment of contact press, friction coefficient decreases and the friction power increases.But its increasing velocity is lower than that of contact press.Average friction coefficient should be used in metal plastic deforming process,rather than Coulomb theory.