The Metastable Micro-Nanocrystals and Formation Mechanism of Rapidly Solidified Al-21Si Multi-Alloys

Abstract:

In the present work, rapidly solidified Al-21Si-0.8Mg-1.5Cu-0.5Mn alloys strips was prepared by melt-spinning technique. The microstructure morphology and phase structures of experimental alloy were characterized by means of scanning electron microscopy (SEM), transmission electric microscopy (TEM) and XRD technique. The results show that the grains were refined and the micro-nanocomposite structural were formed under rapid solidification. The nucleation and growth of primary silicon were suppressed and primary silicon could not deposited, meanwhile, α-Al phase was nucleated which prior to eutectic. The microstructure of the Al-21Si alloy was composed of micro-nanostructured α-Al phase and feather-needles-like eutectic α-Al+β-Si phase. The hypereutectic Al-21Si alloy showed the hypoeutectic microstructure. The rapidly solidified Al-21Si alloy microstructure formation mechanism has also been discussed.

• Periodical: Key Engineering Materials (Volume 636)
• Pages: 97-100
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.636.97
• Online since: December 2014
• Authors: Ai Qin Wang, Hui Hui Han, Jing Pei Xie, Ji Wen Li
• Keywords: Competitive Growth, Formation Mechanism, Micro-Nanocrystals, Rapidly Solidification

References

[1] A.M. Zhao, W.M. Mao. The Chinese Journal of Nonferrous Metals, 2001, 11 (5), 827.

[2] Y.Y. Li, D.T. Zhang. Trans. Nonferrous Met. Soc. China, 2002, 12(5), 878.

[3] P. Kapranos, D.H. Kirkwood. Journal of Materials Processing Technology, 2003, 135, 271.

[4] S.P. Nikanorov, M.P. Volkov. Materials Science and Engineering A, 2005, 390, 63.

[5] Z.H. Zhang, X.F. Bian and Z.Q. Wang. Journal of Alloys and Compounds, 2002, 339, 180.

[6] M. Gupta, S. Ling. Journal of Alloys and Compounds, 1999, 287, 284.

[7] S.K. Das, J.H. Perepezko. Materials Science and Engineering A, 2001, 304-306, 159.

[8] H.W. Zhang, J.Q. Wang and K. Lu. Acta metallurgica sinica, 2002, 38(6), 609.

[9] Z.S. Zhen, A.M. Zhao. The Chinese Journal of Nonferrous Metals, 2000, 10 (6), 815.

[10] C.L. Xu, Q.C. Jiang. Materials Science and Engineering A, 2006, 437, 451.

[11] F.C. Robles Hernandez, M.B. Djurdjevic, W.T. Kierkus. Materials Science and Engineering A, 2005, 396, 271.

[12] S.M. Li, B.L. Ma. Science in china Ser. E Engineering & Materials Science, 2005, 35(3), 479.

[13] H.Q. Hu. The principle of metal solidification, China Machine Press, Beijing, 2000, 173.

[14] G. Chen, H.Z. Fu. New Metallic materials of Non-equilibrium solidification, Science Press, Beijing, 2004, 96.

[15] A.Q. Wang. Study of Modification and Microstructure of Rapid Solidification for High-Si aluminum alloy, Ph. D. Thesis, Zhengzhou University, (2008).