Caractèrisation du frottement au cours de la mise en forme à la tempèrature ambiante

Measuring friction for cold forming processes

¹ Laboratoire de Génie Mécanique, MECAMAT, Unité de Recherche associée au C.N.K.S. Université de Valenciennes et du Hainaut Cambrésis, Valenciennes, France
² Actuellement à l'ICAM, Département Génie Mécanique, Lille, France

Abstract

The surface mechanic behaviour in metal forming operations is studied by a new indentation-translation test which involves a localized plastic deformation in the workpiece surface vicinity. Applied loads are measured during the indenter displacement and friction stress, contact pressure are deduced from mechanical analyses for the proposed test.

Identification of surface constitutive equations is performed with the test for spheroidized low carbon steel workpieces. A reference zinc plwsphating and stearate soaping treatment is used for the presented results. Experimental results are identified by a se cond order relationship related to contact pressure and Jlow shear stress. Finally, the influence of sliding velocity is enhanced.