Determination of Processing Windows for the Hot Stamping of AA7075

Abstract:

Hot stamping of aluminium alloys is a tailored forming process, with the assigned processing windows determining the quality of each hot stamped component in terms of its post-form strength. In this work, a processing window calculator, ‘Tailor’, was developed in order to define the optimal processing parameters that should be used in a production line to successfully produce a component with the desired post-form strength using hot stamping. ‘Tailor’ was developed using the results of forming tests, air-cooling tests and multi-stage artificial ageing tests, which provided guidance on the values for the die closing force, transfer time and artificial ageing time to be used in the hot stamping process. The effectiveness of ‘Tailor’ was demonstrated in two case studies.

• Periodical: Key Engineering Materials (Volume 716)
• Pages: 402-412
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.716.402
• Online since: October 2016
• Authors: Qun Li Zhang, Kang Ji, Omer El Fakir, Xiao Chuan Liu, Li Liang Wang*
• Keywords: AA7075, Hot Stamping, Processing Windows, Tailor

References

[1] H. Hao, Z. Liu, F. Zhao, W. Li, W. Huang, Scenario analysis of energy consumption and greenhouse gas emissions from China's passenger vehicles, Energy, 91(2015) 151-159.

DOI: 10.1016/j.energy.2015.08.054

[2] O. Fakir, L. Wang, D. Balint, J. Dear, J. Lin, Numerical study of the solution heat treatment, forming and in-die quenching (HFQ) price on AA 5754, Int. J. Mach. Tool Manu. 87 (2014) 39-48.

DOI: 10.1016/j.ijmachtools.2014.07.008

[3] Davis, Review of technical literature and trends related to automobile mass-reduction technology, Institute of Transportation Studies, University of California, Davis, (2010).

[4] W.S. Miller, L. Zhuang, J. Bottema, A. Wittebrood, P. De Smet, A. Haszler, A. Vieregge, Recent development in aluminium alloys for the automotive industry, Mater. Sci. Eng. A. 280 (2000) 37-49.

DOI: 10.1016/s0921-5093(99)00653-x

[5] P. Lequeu, P. Lassince, T. Warner and G.M. Raynaud, Engineering for the future: weight saving and cost reduction initiatives, Aircr. Eng. Aerosp. Tec. 73 (2001) 147-159.

DOI: 10.1108/00022660110386663

[6] I.J. Polmear, Light Alloys: Metall. Light Met., third ed., Wiley Press, New York, (1995).

[7] M. Mohamed, J. Foster, J. Lin, Solution heat treatment in HFQ process, Steel Res. Int., 11 (2008) 160-167.

[8] M.F. Novella, A. Ghiotti, S. Bruschi, P.F. Bariani, Ductile damage modeling at elevated temperature applied to the cross wedge rolling of AA6082-T6 bars, J. Mater. Process. Tech. 222 (2015) 259-267.

DOI: 10.1016/j.jmatprotec.2015.01.030

[9] R.P. Garrett, J. Lin, T.A. Dean, An investigation of the effects of solution heat treatment on mechanical properties for AA 6xxx alloys: experimentation and modelling, Int. J. Plasticity. 21 (2005) 1640-1657.

DOI: 10.1016/j.ijplas.2004.11.002

[10] C. M Abreu, M.J. Cristobal, R. Figueroa, G. Pena, Wear and corrosion performance of two different tempers (T6 and T73) of AA7075 aluminium alloy after nitrogen implantation, Appl. Surf. Sci. 327 (2015) 51-61.

DOI: 10.1016/j.apsusc.2014.11.111

[11] S.V. Emani, J. Benedyk, P. Nash, D. Chen, Double aging and thermomechanical heat treatment of AA7075 aluminum alloy extrusions, J. Mater. Sci. 44 (2009) 6384–6391.

DOI: 10.1007/s10853-009-3879-8

[12] X. Fan, Z. He, S. Yuan, P. Lin, Investigation on strengthening of 6A02 aluminum alloy sheet in hot forming-quenching integrated process with warm forming-dies, Mater. Sci. Eng. A. 587 (2013) 221-227.

DOI: 10.1016/j.msea.2013.08.059

[13] M.J. Starink, N. Gao, L. Davin, J. Yan, A. Gerezo, Room temperature precipitation in quenched Al–Cu–Mg alloys: a model for the reaction kinetics and yield strength development, Philos. Mag. 13 (2005) 1395-1417.

DOI: 10.1080/14786430412331333374

[14] X. Liu, K. Ji, O. Fakir, J. Liu, Q. Zhang, L. Wang, Determination of Interfacial Heat Transfer Coefficient in the Hot Stamping of AA7075. 4th international Conference on New Forming Technology, (2015).

DOI: 10.1051/mfreview/2016017

[15] Y. Xiao, Q. Pan, W. Li, X. Liu, Y. He, Influence of retrogression and re-aging treatment on corrosion behaviour of an Al-Zn-Mg-Cu alloy, Mater. Design 32 (2011) 2149-2156.

DOI: 10.1016/j.matdes.2010.11.036

[16] X. Huang, Q. Pan, B. Li, Z. Liu, Z. Huang, Z. Yin, Microstructure, mechanical properties and stress corrosion cracking of Al-Zn-Ma-Zr alloy sheet with trance amount of Sc, J. Alloy. Compd. 650 (2015) 805-820.

DOI: 10.1016/j.jallcom.2015.08.011

[17] J. Lin, T.A. Dean, R.P. Garrett, A process in forming high strength and complex-shaped Al-alloy sheet components, British Patent, UK, (2008).

[18] Z. Duan, B. He, Extended Reynolds analogy for slip and transition flow heat transfer in micro channels and nanochannels, Int. J. Heat Mass Transf. 56 (2014) 25-30.

DOI: 10.1016/j.icheatmasstransfer.2014.04.022

[19] P.T. Tsilingiris, Modeling heat and mass transport phenomena at higher temperatures in solar distillation systems - The Chilton-Colburn analogy, Sol. Energy. 84 (2010) 308-317.

DOI: 10.1016/j.solener.2009.11.012

[20] A. Bejan, Convection Heat Transfer, fourth ed., John Wiley & Sons, New Jersey, (2013).

[21] D. Mclean, Understanding Aerodynamics: Arguing from the Real Physics, second ed., John Wiley & Sons, Chichester, (2012).

[22] A. Myerson, Handbook of Industrial Crystallization, Butterworth-Heinemann, second ed., Oxford, (2002).

[23] J. Tu, K. Inthavong, G. Ahmadi, Computational Fluid and Particle Dynamics in the Human Respiratory System, Springer Sci. &Business Media, (2012).

[24] S. Gang and C. Alfred, Early-stage precipitation in Al–Zn–Mg–Cu alloy, Acta Mater., 52(2004) 4503-4516.

DOI: 10.1016/j.actamat.2004.06.025

[25] R. Ferragut, A. Somoza, A. Tolley, I. Torriani, Precipitation kinetics in Al–Zn–Mg commercial alloys, J. Mater. Process. Technol., 41(2003)35-40.

DOI: 10.1016/s0924-0136(02)01044-0

[26] L.K. Berg, J. Gjønnes, V. Hansen, X.Z. Li, M. Knutson-Wedel et al., GP-zones in Al–Zn–Mg alloys and their role in artificial aging, Acta Mater. 49 (2001) 3443-3451.

DOI: 10.1016/s1359-6454(01)00251-8