Pre-treatment to Improve the Bake-hardening Response in the Naturally Aged Al-Mg-Si Alloy

J Mater Sci Technol ›› 2011, Vol. 27 ›› Issue (3): 205-212.

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Pre-treatment to Improve the Bake-hardening Response in the Naturally Aged Al-Mg-Si Alloy

Chin-Hui Shen

Department of Mechanical Engineering, Army Academy No.750, Longdong Rd., Zhongli City, Taoyuan County 320, Taiwan, China

Received:2010-06-01 Revised:2010-08-14 Online:2011-03-28 Published:2011-03-21
Contact: Chin-hui Shen

Abstract

Abstract: This paper describes pre-treatment methods to improve the bake-hardening response of naturally aged AA6022 (Al-0.6Mg-1.0Si), which is an alloy used in automotive body panels. These methods are used to accelerate the artificial aging process, which proceeds 30-day period of natural aging. The precipitation behavior of the sheets of this aluminum alloy was analyzed by differential scanning calorimetry (DSC) and electrical conductivity measurements, and subsequently confirmed by microstructure observations by transmission electron microscopy (TEM). Tensile tests and microhardness measurements were performed to determine the mechanical properties of the samples. Under simulated paint-baking conditions (30 min at 170°C), the microhardness and the yield strength (YS) of the pre-strained + pre-aged samples were found to be 113 HV and 225 MPa, respectively. These values are considerably higher than those of pre-aged samples, and they did not decrease significantly during the initial stage of artificial aging.

Key words: Pre-aging, Pre-straining, Natural aging and Bake hardening

Chin-Hui Shen. Pre-treatment to Improve the Bake-hardening Response in the Naturally Aged Al-Mg-Si Alloy[J]. J Mater Sci Technol, 2011, 27(3): 205-212.

References

[1 ] W.S. Miller, L. Zhuang, J. Bottema, A.J. Wittebrood, P. De Smet, A. Haszler and A. Vieregge: Mater. Sci. Eng. A, 2000, 280(3), 37.

[2 ] T. Sakural: R & D: Research and Development Kobe Steel Engineering Reports, 2007, 57(2), 45.

[3 ] L. Zhuang, R. De Haan, J. Bottema, C.T.W. Lahaye and P.D. Smet: Mater. Sci. Forum, 2000, 331, 1309.

[4 ] S. Kleiner, C.H. Henkel, P. Schulz and P.J. Uggowitzer: Aluminium, 2001, 77, 185.

[5 ] J.D. Bryant: Automotive Alloys, eds S.K. Das and G.J. Kipouros, The Minerals, Metals & Materials Society, Warrendale, PA, 1997, 19.

[6 ] S. Esmaeili, D.J. Lloyd and W.J. Poole: Acta Mater., 2003, 51, 3467.

[7 ] Y. Birol: Mater. Sci. Eng. A, 2005, 391, 175.

[8 ] L. Zhen and S.B. Kang: Mater. Sci. Technol., 1998, 14, 317.

[9 ] S.B. Kang, L.Zhen and H.W. Kim: Mater. Sci. Forum, 1996, 217-222, 827.

[10] M. Saga, Y. Sasaki, M. Kikuchi, Z. Yan and M. Matsuo: Mater. Sci. Forum, 1996, 217-222, 821.

[11] L. Zhen and S.B. Kang: Scripta Mater., 1997, 10, 1089.

[12] L. Zhen, S.B. Kang and H.W. Kim: Mater. Sci. Technol., 1997, 13, 905.

[13] K. Matsuda, T. Kawabata, T. Naoi, Y. Uetani, S. Rengakuji, T. Sato, A. Kamio and S. Ikeno: J. Jpn. Inst. Met., 1998, 62, 827.

[14] A. Deschamps, F. Livet and Y. Brechet: Acta Mater., 1999, 47, 281.

[15] R.S. Yassar, D.P. Field and H. Weiland: Metall. Mater. Trans. A, 2005, 36(8), 2059.

[16] Y. Birol: Scripta Mater., 2005, 52, 169.

[17] S. Ceresara and P. Fiorini: Mater. Sci. Eng., 1972, 10, 205.

[18] P. Gomiero, A. Reeves, A. Pierre, F. Bley, F. Livet and H. Vichery: in the 4th Int. Conf. on Aluminum Alloys, Their Physical and Mechanical Properties, 1994, 644.

[19] J.E. Hatch: Aluminum: Properties and Physical Metallurgy, American Society for Metals, Metals Park, Ohio, USA, 1984, 206.

[20] D.W. Pashley, J.W. Rhodes and A. Sendorek: J. Inst. Met., 1966, 94(2), 41.

[21] C.D. Marioara, S.J. Andersen, J. Jansen and H.W. Zandbergen: Acta Mater., 2001, 492, 321.

[22] I. Kovacs, J. Lendvai and E. Nagy: Acta Metall., 1972, 20, 975.

[23] W.F. Miao and D.E. Laughlin: Scripta Mater., 1999, 40, 873.

[24] W.F. Miao and D.E. Laughlin: Metall. Mater. Trans. A, 2000, 31(2), 361.

[25] T. Mahoto, O. Fumiyoshi, S. Tomohisa and F. Kouichiro: Mater. Sci. Forum, 1996, 217-222, 815.

[26] M.H. Mulazimoglu, R.A.L. Drew and J.E. Gruzelski: J. Mater. Sci. Lett., 1989, 8, 297.

[27] I. Dutta and S.M. Allen: J. Mater. Sci. Lett., 1991, 10, 323.

[28] D.E. Laughlin and W.F. Miao: Automotive Alloys II, ed S.K. Das, TMS, Warrendale, PA, 1998, 63.

[29] G.A. Edwards, K. Stiller, G.L. Dunlop and M.J. Couper: Acta Mater., 1998, 46, 3893.

[30] R.S. Yassar, D.P. Field and H. Weiland: Scripta Metall., 2005, 53, 299.

[31] H.S. Zurob, C.R. Hutchinson, Y. Brechet and G. Purdy: Acta Mater., 2002, 50, 3075.

[32] F.C. Larche: Dislocation in Solids, ed F.R.N. Nabarro, North Holland, Amsterdam, 1979, 137.

[33] A.J. Ardell: Acta Metall., 1972, 20(4), 601.

Pre-treatment to Improve the Bake-hardening Response in the Naturally Aged Al-Mg-Si Alloy

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