Effect of Cooling Rate on Modification and Grain Refinement of 4032 Aluminum Alloy

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Effect of cooling rate on modification and refinement of 4032 aluminum alloy has been investigated at cooling rates of 0.7~4.5 K/s. Sr is used to modify eutectic silicon and B is used to refine primary α-Al grains. Modification level of eutectic silicon and refining results of primary α-Al are characterized quantitatively by Lp based on the perimeter of eutectic silicon particles and the maximum grain length D, respectively. As the cooling rate decreases, the needle-like eutectic silicon particles increases and the modification level reduces with a constant Sr content. Influenced by alloying elements such as Mg, Cu and Ni, the modification level is very low at the lowest cooling rate of 0.7 K/s, but properly increasing Sr content in the melt can improve the modification. At the cooling rates of 0.7~4.5 K/s, the element B can transform coarse columnar dendritic α-Al grains to equiaxed ones, and controlling the ratio of Sr and B is a valid technique to avoid mutual poisoning. On the conditions of present experiments, the Sr content of 350 ppm and Sr:B ratio of about 1.1 are rational to modify eutectic silicon and refine primary α-Al grains simultaneously.

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Periodical:

Edited by:

Qing Liu, Jian-Feng Nie, Robert Sanders, Zhihong Jia and Lingfei Cao

Pages:

20-26

DOI:

10.4028/www.scientific.net/MSF.877.20

Citation:

Y. F. Wu et al., "Effect of Cooling Rate on Modification and Grain Refinement of 4032 Aluminum Alloy", Materials Science Forum, Vol. 877, pp. 20-26, 2017

Online since:

November 2016

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$35.00

* - Corresponding Author

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