Semisolid Sinter-Forging of Hyper-Eutectic Al-Si Alloy Using Rapid Resistance Heating

Abstract:

In casting of hyper-eutectic Al-Si alloys, primary Si grains often grow, which deteriorates mechanical properties of the castings. In this study, an attempt was made to obtain hyper-eutectic Al-Si alloy parts without coarse primary Si grains by taking another route of sinter-forging. The sinter-forging taken up here is semisolid one. In this sinter-forging, a green compact billet of hyper-eutectic Al-25mass% Si alloy powder is rapidly resistance-heated into a semisolid state to promote the sintering and then upset-forged into a disc shape, and the performance was examined by paying special attention to the behavior of primary Si grains in the relation to the resistance heating condition.

• Periodical: Materials Science Forum (Volumes 654-656)
• Pages: 1408-1411
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.654-656.1408
• Online since: June 2010
• Authors: Seijiro Maki, Masayuki Noda, Eitoku Nakanishi
• Keywords: Hyper Eutectic Al-Si Alloy, Powder Metal, Resistance Heating, Semi-Solid, Sinter-Forging

References

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[3] S. Maki, K. Suzuki and K. Mori: Mater. Sci. Forum, Vol. 561-565 (2007), pp.925-928.

[4] S. Maki and K. Mori, in: Ti-2007 Science and Technology, edited by M. Niinomi, S. Akiyama, M. Hagiwara, M. Ikeda and K. Maruyama, Vol. 2 (2007), pp.877-880, The Japan Institute of Metals.

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