Measurement of Friction in Drawing, Extrusion, and Rolling

Abstract

In the processes of plastic forming of metals, friction between the metal and the tools (dies) plays a crucial part. Forces, flow patterns, tool wear, and surface finish of the product as well as the capacity of the equipment (in rolling), all are affected by friction. A complete analysis of any process considers the coefficient of friction as a variable. A quantitative knowledge of the value of the coefficient of friction acting during processing is desired. This work proposes an experimental procedure for the evaluation of the coefficient of friction for processes like wire drawing and rod extrusion through an open die, for hydrostatic extrusion and for rolling.