Simulation and Research on the Rheocasting Process of 7075 Aluminum Alloy

Abstract:

Taking the 7075 aluminum alloy as an example, this paper did some simulation work on temperature, flow field and shrinkage porosity distribution in the rheocasting process using the simulation casting software PROCAST. Effects of the casting temperature and filling speed on casting quality as well as segregation phenomenon of solid and liquid phases were discussed in this paper. Proper ranges of casting temperature and filling speed were obtained by the simulation. Good quality parts without shrinkage porosity were obtained in validation test using the casting temperature of 622~625°C and filling speed of 40mm/s. Rheocasting was an important forming method using semi-solid melt to manufacture metal parts directly. It was a promising trend of semi-solid forming industry which had shorter process, higher efficiency and lower energy consumption compared to SIMA method [1-4]. Rheocasting was generally applied to casting aluminum alloy but seldom to wrought aluminum alloys. The 7xxx series aluminum was generally manufactured though wrought or rolling technique to obtain dense parts with high strength. But few of them were produced directly through casting method without casting flaws[5-6].To process the 7xxx series aluminum by rheocasting method would further expand the application of wrought aluminum alloy, so it is essential to do some research on the rheocasting technique for wrought aluminum alloy. Taking the 7075 aluminum alloy as an example, this paper did some simulation work on temperature, flow field and shrinkage porosity distribution in the rheocasting process using the simulation casting software PROCAST. The effects of casting temperature and filling speed on the casting quality as well as the segregation phenomenon of solid and liquid phases were discussed in this paper. Proper ranges of casting temperature and filling speed were obtained by the simulation.

• Periodical: Advanced Materials Research (Volumes 129-131)
• Pages: 482-489
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.129-131.482
• Online since: August 2010
• Authors: Nan Li, Shu Ming Xing, Pei Wei Bao
• Keywords: 7075, Procast, Rheocasting, Segregation, Semi-Solid, Simulation, Solid Fraction

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