Effect of Annular Electromagnetic Stirring Process on Solidification Microstructure of 7075 Aluminium Alloy

Abstract:

7075 aluminum alloy melt conditioned by annular electromagnetic stirring(A-EMS) was cast in the TP1 mould, and the effects of pouring temperature, stirring current, stirring frequency and annular gap width on microstructures were analyzed. The A-EMS process exhibits superior grain refinement and remarkable structure homogeneity compared with conventional casting(N-EMS) and conventional electromagnetic stirring casting(EMS). With the increasing of the pouring temperature, the microstructures of the sample conditioned by A-EMS are inclined to become coarse and non-uniform compared with which have the more serious inclination conditioned by N-EMS. With the stirring current or stirring frequency increasing, the rosette-like or dendritic primary α(Al) phase decreases significantly on the sample microstructures, and the non-dendritic primary α(Al) phase is finer and more spherical. Narrow annular gap is advantageous to obtain uniformly fine spherical solidification microstructures.

• Periodical: Advanced Materials Research (Volumes 652-654)
• Pages: 2418-2426
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.652-654.2418
• Online since: January 2013
• Authors: Zhi Hua Gao, Jun Xu, Zhi Feng Zhang, Meng Ou Tang
• Keywords: 7075 Alloy, Annular Electromagnetic Stirring, Solidification Microstructure

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