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Weidenmann, K. A.; Klaska, A. M.; Kerscher, E.; Löhe, D.:
In: Praktische Metallographie, 45  533-545, 2008
Given the background of proven improvement possibilities in the mechanical properties of extrusion profiles through composite billet pressing of metallic matrix materials with metallic reinforcing elements, a question arises as to the potential of hybrid composite billet pressing using metallic and non-metallic components. In this paper, hybrid billet profiles based on the aluminum alloy EN AW-6060, reinforced with a composite wire of 60 volume-% of Nextel aluminum oxide fibers and 40 volume-% of EN AW-1099, as well as based on the composite material EN AW-6061, reinforced with 15 volume-% Al2O3 particles, reinforced with a spring steel wire, were manufactured and characterized metallographically. By way of a specially constructed extrusion apparatus, operated on a universal testing machine, test samples of 20 mm length were produced at extrusion temperatures of 450° C. The subsequent characterization in light-optical and scanning electron microscopes shows a fracture-free embedding of the wires in the matrix materials which indicates a good wire/matrix bonding. The assumption is that the hybrid extrusion shows a marked improvement of the mechanical properties compared to non-hybrid profiles. No tearing of the wire reinforcements occurred during the extrusion process. Very high extrusion forces are necessary for the production of hybrid billet profiles particularly during usage of composite matrices as has been shown for composite billet extrusion of metallic components. In addition, usage of reinforced matrices will result in high wear and tear of tools.