Experimental characterization of sliding friction: Crossing from deformation to plowing contact

A pin-on-disk tribometer was used to investigate the influence of several p arameters on the sliding friction coefficient between hard and deformable s urfaces. Pin (1045 tool steel) and disk (aluminum 1100) were utilized to si mulate the interaction of a harder tool sliding relative to a softer deform able workpiece. Friction coefficient results were obtained at 561 distinct operating conditions by varying the ball diameter (3.18, 6.35, and 12.70 mm ), lubricant toil B, oil A, and grease), sliding speed (0.1 similar to0.8 m /s) and normal load (50 similar to 1200 g). Several relationships which cha racterize the behavior of the friction coefficient as a function of the she ar factor, tau (k), are established. the importance of these relationships, as related to stamping and forming processes, is discussed. [S0742-4787(00 )01703-3].