The Effect of Ageing on Impact Toughness and Microstructure of 2024 Al-Cu-Mg Alloy

The present study aims at determining the effect of ageing on the impact toughness and microstructure of 2024 Al-Cu - Mg alloy. Following the 2 h solutionizing treatment at 450°C and water quench, the specimens were aged at 200°C for various periods (1 to 18 h). The precipitation stages during ageing were monitored by hardness measurements. For each specimen group, Charpy impact and hardness tests were carried out. During ageing the impact toughness of the alloy first increased, and then, following a maxima decreased due to the precipitation of intermediate phases, finally it reached its minimum at the peak hardness. Correlations between hardness and impact toughness were investigated.

• Swami Naidu Gurugubelli

• Ageing
• alloy
• hardness
• microstructure.

[1] T.Kobayashi, Mater. Sci. Eng. A286 (2000) 333-341.
[2] N.Ryum, Acta Metall. 16 (1968) 327-332.
[3] I.Kovacs, J.Lendvai, T.Ungar, T.Turmezey, G.Groma, Acta Metall. 25
(1977) 673-680.
[4] G.G.Garrett, J.F.Knott, Metal. Trans. 9A (1978) 1187-1201.
[5] A. Melander, P.A.Persson, Acta Metall. 26 (1978) 267-278.
[6] T.S.Srivatsan, J Mater. Sci. 27 (1992) 4772-4781.
[7] A.K.Mukhopadhyay, Q.B.Yang, S.R.Singh, Acta Metall. Mater. 42
(1994) 3083-3091
[8] X.Z.Li, V.Hansen, J.Gjonnes, L.R.Wallenberg, Acta Mater. 47 (1999)
2651-2659.
[9] S.P.Ringer, K.Hono, Mater. Charact. 44 (2000) 101-131.
[10] G.Waterloo, V.Hansen, J.Gjonnes, S.R.Skjervold, Mater. Sci. Eng.
A303 (2001) 226-233.
[11] D. Dumont, A. Deschamps, Y. Brechet, Mater. Sci. Eng. A356 (2003)
326-336.
[12] D.J.Hagemaier, R.Kleint, Metal Progress (1964) 115-118.
[13] Y.Gefen, M.Rosen, Mater. Sci. Eng. 8 (1971) 246-247.
[14] Y.Gefen, M.Rosen, A.Rosen, Mater. Sci. Eng. 8 (1971) 181-188.
[15] D.J.Hagemaier, Mater. Eval. 40 (1981) 962-969.
[16] M.Rosen, E.Horowitz, S.Fick, R.C.Reno, R.Mehrabian, Mater. Sci.
Eng. 53 (1982) 163 -177.
[17] M.Rosen, E.Horowitz, L.Swartzendruber, S.Fick, R.Mehrabian, Mater.
Sci. Eng. 53 (1982)191-198.
[18] M.Natan, R.A.Chihoski, J Mater. Sci. 18 (1983) 3288-3298.
[19] M.Rosen, L.Ives, S.Ridder, F.Biancaniello, R.Mehrabian, Mater. Sci.
Eng. 74 (1985) 1-10.
[20] J.Champlin, J.Zakrajsek, T.S.Srivatsan, P.C.Lam, M.Manoharan, Mater.
Design 20 (1999) 331-341.
[21] D.Sun, X.Sun, D.O. Northwood, J.H.Sokolowski, Mater. Charact. 36
(1996) 83-92.
[22] G.T.Hahn, A.R.Rosenfield, Metall. Trans. 6A (1975) 653-670.
[23] I.Kirman, Metal. Trans. 2 (1971) 1761-1770.