Transient Rheological Behavior of Semisolid SEED-Processed 7075 Aluminum Alloys in Rapid Compression

Bolouri, Amir; Chen, X. Grant

Abstract

© 2018, The Author(s). The transient rheological behavior and microstructure evolution of semisolid SEED-processed 7075 aluminum alloys were studied using the rapid compression tests. The effects of the TiB2 grain refinement on the grain morphology and size of semisolid slurries were investigated. Results indicated that the grain refiner could reduce the grain size and improve the globularity of α-Al grains. The grain-refined alloy can be easily deformed at a wide range of solid contents (0.42 to 0.53 Fs), in which the deformation level appears to be independent from the solid content. Under the transient state, the apparent viscosity decreased with increasing shear rate to a minimum value and followed by an increase as the shear rate decreased. The apparent viscosity of the base alloy exhibited a dependency on the solid content, while the apparent viscosity of the grain-refined alloy in the decreasing or increasing shear rate periods was not substantially influenced by the solid content. The viscosity as a function of applied shear rate can be described using the power law viscosity model. The differences in the flow behavior index (n) and the consistency index (k) for two alloys were discussed.

• Journal Article Type: Article
• Acceptance Date: Jul 11, 2018
• Online Publication Date: Aug 1, 2018
• Publication Date: Oct 1, 2018
• Deposit Date: Sep 21, 2018
• Publicly Available Date: Sep 21, 2018
• Journal: Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science
• Print ISSN: 1073-5615
• Electronic ISSN: 1543-1916
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 49
• Issue: 5
• Pages: 2858-2867
• DOI: https://doi.org/10.1007/s11663-018-1372-y
• Public URL: https://uwe-repository.worktribe.com/output/863274
• Publisher URL: http://dx.doi.org/10.1007/s11663-018-1372-y
• Contract Date: Sep 21, 2018