Morphological Analysis Of Ssm Al-4.5 Wt.% Cu Measured By The Rheocast Quality Index

There is a direct relationship between grain size obtained from macrostructure characterisation and the globule size and shape factor, obtained from microstructure characterisation: the smaller the grain size, the smaller the globule size and shape factor. Due to this a rheocast quality index (RQI = globulesize/(grainsize × shapefactor)) was used to evaluate the Al-4.5 wt.% Cu alloy produced by strain induced melting activation (SIMA). The structure that presents the smallest grain size, the smallest shape factor, and the most homogeneous and globular size of the primary phase, has the best RQI and consequently the best behaviour in the semi-solid forming. Four different as-cast structures were cold rolled to obtain 20 and 40% deformation and were partially melted at 635°C at holding times of 5min. Both, macro- and microstructure were characterised. © 2003 Elsevier Science B.V. All rights reserved.143-1441195201Tzimas, E., Zavaliangos, A., Lawley, A., (1998) Proceedings of the Fifth Conference on Semi-solid Processing of Alloys and Composites, pp. 345-352. , Golden, CO, USALeathan, A.G., Lawley, A., (1993) Int. J. Powder Metall., 29 (4), pp. 321-329Flemings, M.C., (1991) Metall. Trans. A, 22, pp. 957-981Kirkwood, D.H., (1994) Int. Mater. Rev., 39 (5), pp. 173-189Ito, Y., Flemings, M.C., Cornie, J.A., (1992) Proceedings of the TMS Symposium on Nature and Properties of Semi-solid Materials, pp. 3-17. , San Diego, CA, USAApaydin, N., Prabhakar, K.V., Dohert, R.D., (1980) Mater. Sci. Eng., 46, pp. 145-150Niroumandi, B., Xia, K., (2000) Mater. Sci. Eng. A, 283, pp. 70-75Loué, W.R., Suéry, M., (1995) Mater. Sci. Eng. A, 203, pp. 1-13Salvo, L., Loué, W.R., Suéry, M., (1995) ISIJ Int., 35 (6), pp. 798-804Bartos-Tausig, G., Xia, K., (1996) Mater. Sci. Forum, 217-222, pp. 323-328Paes, M., Herzig, S., Zoqui, E.J., (2000) Proceedings of the Sixth Conference on Semi-solid Processing of Alloys and Composites, pp. 693-699. , Turim, ItalyZoqui, E.J., Robert, M.H., (2001) J. Mater. Process. Technol., 109, pp. 215-219Zoqui, E.J., Paes, M., Essadiqi, E., (2002) J. Mater. Process. Technol., 120 (1-3), pp. 365-373Zoqui, E.J., Shehata, M.T., Paes, M., Kao, V., Essadiqi, E., (2002) J. Mater. Sci. Eng. A, 325, pp. 38-5