Study on Microstructures and Components Uniformity of 7050 Aluminum Alloy with Annulus Electromagnetic Stirring Casting

Abstract:

7050aluminum alloy billets processed by semi-continuous casting were studied using conventional casting (N-EMS), conventional electromagnetic stirring casting (EMS) and annulus electromagnetic stirring casting (AEMS), respectively. Adopting the method of mathematical statistics, Zn, Mg, Cu chemical component uniformity and the microstructure of 7050 aluminum alloy billets were analyzed. The results showed that the high chemical component uniformity of the AEMS billets were obtained compared with N-EMS and EMS. The Zn, Mg, Cu element component variance was reduced 26% compared with EMS. And the A-EMS process exhibited superior grain refinement and remarkable structure homogeneity, which mainly consisted of rosaceous and nearly globular structure. The average grain size for AEMS sample was 42μm, and the grain shape factor was about 0.68.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 716-721
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.716
• Online since: March 2016
• Authors: Ya Bao Wang, Zhen Lin Zhang, Bao Li, Zhi Hua Gao, Zhi Feng Zhang, Jun Xu
• Keywords: 7050 Aluminum Alloy, Annular Electromagnetic Stirring, Chemical Components, Microstructure, Uniformity

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