Abstract: | An important aspect concerning the processing of metals by plastic deformation is related to the existence of the friction forces between tool and part. The friction forces can determine a great increase of the forming resistance. They are quite hard to measure and consequently, they represent one of the most insecure elements when an analysis of the deformation forces is performed. The friction surface is characterized by microgeometry under dimensional aspect and of distribution law and also under the aspect of asperities deformation. Regardless of the finish degree, the surfaces have asperities that are elastic or plastic deformed or even broken, under the action of a system of forces, velocities and a certain environment. |
