Effect on microstructure and corrosion resistance of semi-solid slurry of 7A04 aluminum alloy by electromagnetic stirring. (6th January 2021)

• Record Type: Journal Article
• Authors: Zhu, Yanli; Xu, Xiaolong; Zhao, Junwen; Hu, Guangzhong
• Is Part Of: Materials research express. Volume 8:Number 1(2021)
• Publication Date: 2021-01-06
• Subjects: 7A04 aluminum alloy -- semi-solid -- phases -- element distribution -- corrosion resistance; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/abd5d7
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: The microstructures and corrosion resistance of electromagnetic stirring (EMS) semi-solid slurry and as-cast 7A04 aluminum alloy were compared in this work. The results show that the primary microstructure of the as-cast 7A04 aluminum alloy is mainly dendritic and columnar dendrite with obvious elements segregation. In contrast, semi-solid processing can effectively form homogeneous and round primary α -Al grains, and significantly reducing element segregation. In addition, the main phases of the two forming methods (as-cast and semi-solid) both involved α -Al, η -MgZn2, θ -Al2 Cu. With the decrease of solidification temperature, the semi-solid alloy formed by electromagnetic stirring increases the precipitation of brittle phase S-Al2 CuMg. The self-corrosion potential of the semi-solid alloy is greater than that of the as-cast alloy, and the polarization curve has obvious passivation characteristics. Semi-solid processing could improve corrosion resistance of 7A04 aluminum alloy obviously.