Microstructural Evolution of Eutectic Al-Si Alloys Produced by Semi-Continuously DC Casting during Heating and Hot-Rolling

Abstract:

Semi-continuously direct chill (DC in short) casting was carried out to modify the size and morphology of eutectic Si particles in eutectic Al-Si alloy. Successively, the size, morphology, distribution characters of eutectic Si particles and the hot plasticity ability of the alloy during heating and hot-rolling were investigated by the observation of optical microstructure characterization and the rolling of wedge bar. The results show that the eutectics in the eutectic Al-Si alloy can be remarkably fined by semi-continuously DC cast. The eutectic Si phase particles will coarsen and spheroidize after holding at 480°C for 2h, which enables eutectic Al-Si alloy to possess excellent hot plasticity free of cracked edge with compression ratio of rolling up to 85% by single pass. Though little difference on the size of spheroidized Si particles during hot rolling can be observed, uniform distribution of the Si particles can be obtained by hot rolling with compression ratio of 85%.

• Periodical: Advanced Materials Research (Volumes 146-147)
• Pages: 1289-1292
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.146-147.1289
• Online since: October 2010
• Authors: Tao Hong, Gang Zhao, Ni Tian, Fu Xiao Yu, Liang Zuo
• Keywords: Al-Si Alloy, Direct Chill Casting, Eutectics

References

[1] A. Ma, M. Takagi, N. Saito, H. Iwata, Y. Nishida, K. Suzuki and I. Shigematsu: Mater. Sci. Eng. A Vol. 408 (2005), p.147.

[2] F. X. Yu, J. Z. Cui, K. Qin, Z. G. Sun and H. Wang, China Patent 200510119550. 6 (2008).

[3] L. Zuo, F. X. Yu, G. Zhao, X. Zhao, Y. L. Yang and Y. L, China Patent 200810137603. 0 (2010).

[4] F. X. Yu, Y. F. Li and J. Z. Cui: Trans. Indian Inst. Met. Vol. 58 (2005), p.591.

[5] F. X. Yu, J. H. Pei, K. Z. He, D. Z. Zhao and L. Zuo: Trans. Indian Inst. Met. 62 (2009), p.347.

[6] M. D. Nave, A. K. Dahle and D. H. StJohn: Acta Mater. Vol. 50 (2002), p.2837.