Session 6 - Components / Semis

Chair: Dr. Peter Furrer
Senior Advisor, Technical Marketing & Communication, Novelis AG, Zürich, Switzerland

13:30-14:00 ALMINOX - The next generation of highly decorative Aluminium

Abstract
Anodized aluminium with dedicated surface appearance from high gloss to satin finish is a differentiating feature for many products, such as decorative automotive parts or any kind of room set-ups. The semi-finished product for the gloss treatment is preferably extruded aluminium, combining functionality with high dimensional accuracy. In particular for decorative parts with a high added value a low scrap rate after final anodozing becomes important. Erbslöh Aluminium GmbH has developed the ALMINOX process exactly for that purpose - minimizing costs during finishing and drastically reducing scrap which is attributed to material defects and which occurs at the end of the finishing process. It is the intention of this paper to address the most common defects and highlight the concept how these material related defects can be minimized.

14:00-14:30 A new Aluminium Alloy for high performance spaceframe profiles

Dipl.-Ing. Horst Gers
Product- and Process Development, HONSEL AG, Soest, Germany

Abstract
Aluminium extrusions especially of the 6xxx series have considerable potential to make cars lighter and thus more economical. Honsel has been supplying aluminium extrusion profiles for spaceframe structures since 1994. Over the time requirements has been changed to higher strength for lower wall thickness including better energy absorbing behaviour. This was the motivation for Honsel and trimet to start an innovative alloy and process development to give these profiles a considerably greater strength and better folding behaviour under load compared to other alloys available. Extrusions made out of this new alloy, named trimal®-52, fulfil the highest demands of the OEMs. This paper describes the most important aspects of the production chain of aluminium profiles for spaceframe application, including the alloy development, the casting process, the development of the die design and the heat treatment during certain steps of production. Results from deformation tests were shown and discussed.

14:30-15:00 Composite extrusion and threading of continuously reinforced aluminium profiles

Abstract
Composite extrusion is an innovative process for the manufacture of reinforced profiles for lightweight structural applications. During extrusion of a regular aluminium billet, reinforcing elements are fed into the welding chamber of a modified die, where they are embedded in the extruded material. In this paper, the manufacturing of composite profiles with different complexity and reinforcing elements is presented. Stainless steel wires or tapes were used as reinforcement. The dies vary in design due to the higher bending stiffness of tapes compared to that of wires. Furthermore, the influence of reinforcing elements on the material flow has been analysed. The processing of composite extrusions is challenging due to the different mechanicalproperties of the materials used. The reinforcement is discrete and its location within the profile is determined. So the influence of the position of the reinforcing elements relative to the tools used in following machining processes is of special interest for process design. The paper describes influences of the reinforcement on the flow-drilling process and subsequent threading operations, which are necessary to join different extrusions to form a complete frame structure or to add mounting parts via screw-coupling. Threads are produced by thread forming, tapping and thread milling. The cross-sections were evaluated qualitatively and pullout tests were conducted to quantify the strength of threads.

15:00-15:30 Powder Extrusion of Aluminium Alloys

Dipl. Ing. Peter Schäffler
Managing Director, Alulight International GmbH, Ranshofen, Germany

Abstract
In this paper two routes for powder extrusion are described with the focus on the industrial application of these techniques. At Alulight® International both routes direct extrusion and Continuous Rotary Extrusion (CRE) are established to compact aluminium based powder materials. The classic route via direct extrusion starts with cold isostatic pressing to consolidate encased powder mixtures to billets with densities of 70 to 80% of theoretical. These powder billets have sufficient green strength to endure proper handling. Since 2004 aluminium components based on a hypereutectic AlSi alloy have been produced for the automotive industry by this method. The PM-stator for the BMW cam-phasor system is produced from a pre-alloyed air atomised AlSi13 cast alloy. This Al-PM-part manufactured by direct extrusion can provide the properties for engine application: light weight materials need to have high mechanical properties in the temperature range from -40 to +160°C, high dimensional stability, excellent wear resistance and low material and processing costs.

15:30-16:00 Hot Profile Extrusion of different Chip Types of Aluminum Alloy 6060

Abstract
This paper presents the recycling of aluminum chips by hot extrusion as an alternative to remelting. Three different types of aluminum alloy 6060 chips are compacted into billets and hot-extruded at 500°C to full rectangular profiles. The hardness and mechanical properties of the extruded profiles produced from chips are on average 10% lower than those extruded from conventionally cast material, but required only 5% of the energy required for re-melting. Furthermore, the influence of chip characteristics on the properties of hot-extruded profiles has been analyzed. The turning chips with the highest deformation grade showed a relative unfavorable behavior with respect to the other chip types. Also, the machinability of the extruded profiles was investigated by drilling tests, which have shown even improved properties due to reduced chip length.