Visualization of Material Flow in Friction Extrusion

Abstract

Friction extrusion was developed at The Welding Institute in the early 1990's; however, the potential of this process has not been extensively examined. With the current emphasis on sustainability with respect to energy and material conservation, friction extrusion has become increasingly relevant as a method of low cost/low energy production of aluminum wire and consolidation of aluminum powder. The friction extrusion process is suitable for recycling of machining waste and as a route to provide feedstock for some additive manufacturing processes. In this presentation we will report on relationships between extrusion parameters (e.g. die rotation rate and extrusion force) and wire microstructure, hardness, and defect content. In addition, marker studies have been used to deduce material flow and, for simple cases, strain, in the extrusion die and billet chamber. Variations in material flow as functions of die geometry will be highlighted.