Adiabatic and friction heating on the open die extrusion of solid and hollow bodies

Abstract

This paper deals with an experimental investigation concerning the open die extrusion (ODE) of three materials of varying physical properties and mechanical properties. Two geometrical configurations (solid and tube) and two methods (by direct and indirect techniques) were considered to examine the influence of these variables in the generation and retention of heat in the deformation zone with the objective of ensuring a greater achievable strain. Studies reveal that solid configuration supports the retention of heat as against tubular configuration. Low thermal conductivity, density, specific heat and high flow stress which characterise 99Ti make this material an excellent candidate for ODE as opposed to AISI 1020 steel and aluminium, which fail to meet all the above physical and mechanical properties. The indirect technique reduces the friction factor and thus enables greater strains to be achieved. 1997 Elsevier Science S.A.