Simulation of Gas and Spray Quenching during Extrusion of Aluminium Alloys

Abstract:

After the extrusion process most aluminium alloy profiles don´t satisfy the necessary strength requirements. An increase of strength can be obtained by age hardening of hardenable aluminium alloys. Age hardening includes the three steps of solution annealing, quenching and aging and is usually carried out in a separate process after extrusion. The integration of the sub-steps solution annealing and quenching in the extrusion process results in a marked reduction of the complete process chain. The applicability of this integration depends primarily on the quenching power of the cooling module and on the quench sensitivity of the aluminium alloy. Using the finite element method the non-steady-state process of quenching the profiles after leaving the extrusion press has been simulated. The boundary conditions for quenching are varied for a gas nozzle field and a spray cooling using heat transfer coefficients based on experiments. The simulation results support the design of gas nozzle fields or spray cooling for the extrusion process of different aluminium alloys.

• Periodical: Key Engineering Materials (Volume 424)
• Pages: 57-64
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.424.57
• Online since: December 2009
• Authors: Michael Reich, S. Schöne, O. Kessler, M. Nowak, O. Grydin, F. Nürnberger, Mirko Schaper
• Keywords: Aluminium Alloy, Gas Quenching, Quenching Simulation, Spray Quenching

References

[1] T. Sheppard: Extrusion of Aluminium Alloys, Kluwer Academic Publishers, Dordrecht, (1999).

[2] D.D. Hall, I. Mudawar, R.E. Morgan, S.L. Ehlers: Validation of a Systematic Approach to Modeling Spray Quenching of Aluminum Alloy Extrusions, Composites, and Continuous Castings, in: JMEPEG vol. 6, 1997, pp.77-92.

DOI: 10.1007/s11665-997-0036-x

[3] T.A. Deiters, I. Mudawar: Optimization of Spray quenching for Aluminum Extrusion, Forging, or Continuous Casting, in: J. Heat Treat. Vol. 7, 1989, pp.9-18.

DOI: 10.1007/bf02833183

[4] C. Kramer, M. Becker: Device for Cooling Extruded Profiles, US Patent 6, 216, 485 B1, (2001).

[5] D.H. Bratland, O. Grong, H. Shercliff, O.R. Myhr, S. Tjotta: Modelling of Precipitation Reactions in Industrial Processing, in: Acta mater. Vol. 45, 1997, pp.1-22.

DOI: 10.1016/s1359-6454(96)00100-0

[6] C. Kramer: Strangabkühlung, in: J. Baumgarten: Strangpressen, DGM-Informationsges. -Verl., 1990, Oberursel, pp.119-129.

[7] N. Jaervstraet, S. Tjotta: A Process Modell for On-Line Quenching of Aluminium Alloys, in: Mateallurgical and Materials Transactions B vol. 27B, 1996, pp.501-508.

[8] C. Krause, E. Wulf, F. Nürnberger, F. -W. Bach: Wärmeübergangs- und Tropfencharakteristik für eine Spraykühlung im Temperaturbereich von 900-100 °C, in: Forsch Ingenieurwes vol. 72 (2008), pp.163-173.

DOI: 10.1007/s10010-008-0079-7

[9] C. Krause: Randschichtvergüten verzahnter Bauteile mittels einer Wasser-Luft-Spraykühlung, Dissertation, Leibniz Universität Hannover (2008).

[10] F. Puschmann: Experimentelle Untersuchung der Spraykühlung zur Qualitätsverbesserung durch definierte Einstellung des Wärmeübergangs, Dissertation, Otto-von-Guericke-Universität Magdeburg (2003).

[11] J.P. Holman: Heat Transfer, McGraw-Hill, New York, (2002).

[12] M. S Hamed: Evaluation of Heat Transfer Coefficients in Water Spray Quenching Systems, 20th Heat Treating Conf. Proc., 2000, ASM International, Vol. II, p.785.

[13] B. Milkereit, O. Kessler, C. Schick: Recording of continuous cooling precipitation diagrams of aluminium alloys, in: Thermochimica Acta, Vol. 492, Elsevier Science (2009), pp.73-78.

DOI: 10.1016/j.tca.2009.01.027

[14] C. Kammer: Aluminium-Taschenbuch, edition 15, Aluminium-Verlag (1998).

[15] W. Hesse, Key to Aluminium, Aluminium-Verlag (2006).

[16] B. Milkereit, C. Schick, O. Kessler: Continuous cooling precipitation diagrams of aluminiummagnesium-silicon alloys, in: J. Hirsch, B. Skrotzki, G. Gottstein (Eds), 11th International Conference on Aluminium Alloys, Deutsche Gesellschaft für Materialkunde e.V., WILEYVCH Weinheim, Aachen, Germany, (2008).

DOI: 10.1201/9781351045636-140000288

[17] R. von Bargen, O. Kessler, H. -W. Zoch: Kontinuierliche Zeit-Ausscheidungs-Diagramme der Aluminiumlegierungen E� AW-7020 und E� AW-7050, in: HTM Z. Werkst. Wärmebeh. Fertigung 62 (2007) 6 pp.285-293.

DOI: 10.3139/105.100440

[18] M. Narazaki, M. Kogawara, M. Qin, Y. Watanabe: Measurement and Database Construction of Heat Transfer Coefficient of Gas Quenching, edited by H. -W. Zoch, Th. Lübben, Proc. 2nd Int. Conf. on Distortion Engineering, 17-19. 09. 08, Bremen, Germany, 2008, pp.327-334.