Using Semi-Solid Extrusion for the Production of Aluminum-Nanocomposite Master Alloys

Abstract:

The production of nanoreinforced aluminum alloys in volume and quality suitable for subsequent shape casting has been problematic. Large specific surface area and high interfacial energy of the particles combined with high surface tension of the aluminum melt makes it difficult to add appreciable numbers of particles to the melt, even when later de-agglomerated by techniques such as ultrasonic cavitation. Previous work by the authors used semi-solid squeeze casting to produce master alloys for dilution into the casting alloy. While the technique was shown to be effective, the master alloy proved difficult to remelt and was expensive to produce. The objective of this new work was to use an extrusion process that could be more readily scaled to produce nanoreinforced aluminum master alloys. This paper describes the process developed for incorporation of nanoparticles using semi-solid extrusion and the results of alloys produced using that process.

• Periodical: Solid State Phenomena (Volumes 217-218)
• Pages: 426-430
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.217-218.426
• Online since: September 2014
• Authors: David Weiss*, Michael Black
• Keywords: Extrusion, Nanocomposite, Semi-Solid Processing

References

[1] X. Li, Y. Yang, D. Weiss, Ultrasonic Cavitation Based Dispersion of Nanoparticles in Aluminum Melts for Solidification Processing of Bulk Aluminum Nanacomposite: Theoretical Study, Fabrication and Characterization. AFS Transactions 2007, Paper 07-133.

[2] P. Shanmughasundaram, R. Subramanian, G. Prabhu, Some Studies on Aluminum – Fly Ash Composites Fabricated by Two Step Stir Casting Method. European Journal of Scientific Research, 63 No. 2 (2011), 204-218.

DOI: 10.4028/www.scientific.net/amr.488-489.775

[3] D. Weiss, M. Black, The Use of High Pressure Direct Squeeze Casting for Semi-Solid Processing of Aluminum Based Nano Composites. Solid State Phenomena Vols. 192-193 (2013) pp.72-75.

DOI: 10.4028/www.scientific.net/ssp.192-193.72

[4] J. Ehrstrom, W. Kool, Migration of Particles During Extrusion of Metal Matrix Composites. Journal of Materials Science Letters June 1988, Volume 7, Issue 6, pp.578-580.

DOI: 10.1007/bf01730299

[5] S. Luo, J. Jiang, Y. Wang, D. Teng, L. Zu, Interface and Microstructure Characteristics of SiCp/2024 Aluminum Alloy Composite. Transactions Nonferrous Met. Soc. China Volume 13 (Feb. 2013).