Deformation Process Modeling of DRA Extrusions

The lack of fully developed extrusion design tools for Discontinuously Reinforced Aluminum (DRA) such as finite element simulation codes will continue to impede market penetration of this promising aerospace material. There is limited motivation on the part of the aluminum extrusion industry to develop finite element codes given the low cost of aluminum and the use of common tool steels for extrusion dies. The design tools this proposal seeks to establish will reduce the lead-time and cost of developing DRA extrusions, expand the manufacturing infrastructure, and grow the market for DRA. The objectives of Phase I are, 1)documentation of critical extrusion process parameters such as ram velocity, extrusion pressure, billet and container pre-heat temperatures, and extrusion die temperatures through the use of thermocoupled tooling and extrusion equipment, 2)a verified finite element simulation model for DRA shear face die extrusions based on DEFORM software, 3) an initial DRA property database specific to deformation processing composed of compression flow stress data that will aid not only the modeling of extrusion but any bulk fabrication process such as rolling, forging, etc., and 4)Preliminary n, as well as preliminary guidelines for die bearing land lengeh.