Analysis of Extrusion Conditions for Hard Aluminum Alloys

摘要

During the extrusion of hard aluminum alloys, exit metal temperature in the die opening determines both the maximum speed and the mechanical properties of the extrudate. An engineer needs process equations, which relate the input parameters, such as billet temperature, extrusion ratio, ram speed, and tooling dimensions, to extrudate temperature. Scaling factors, heat transmission in longitudinal and radial directions, heat generation, heat exchange between the billet and tools, and physical properties of the extruded alloy are evaluated in non- dimensional form.. After the permissible exit temperature has been decided from the incipient melting temperature of a given alloy melt, the input conditions can be decided from the above analyses. Through these approaches, quasi-steady-state processing can provide good, uniform, and stable extrusion properties and high productivity.