Relationship between cooling rate, microstructure evolution, and performance improvement of an Al–Cu alloy prepared using different methods. (4th November 2020)

• Record Type: Journal Article
• Authors: He, Chen; Yu, Wei; Li, Yong; Wang, Zhaodong; Wu, Di; Xu, Guangming
• Is Part Of: Materials research express. Volume 7:Number 11(2020)
• Publication Date: 2020-11-04
• Subjects: Al–Cu alloy -- casting -- twin-roll casting -- cooling rate -- microstructure evolution -- mechanical properties; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/abc4f9
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: The relationship between the cooling rate and microstructure evolution and the performance improvement of an Al–4.5 wt% Cu alloy prepared using different casting methods was investigated. The microstructure evolution, solute element distribution, and mechanical properties of specimens prepared using different cooling rates were systematically investigated using multi-scale optical microscopy, scanning electron microscopy, transmission electron microscopy, tensile testing, and hardness testing. Upon increasing the cooling rate from 1.65 to 117.3 K s −1, the average grain size, secondary dendrite arm spacing, and width and area fraction of eutectic phases significantly decreased, and the density of the precipitated phase, super-saturation degree of solute elements, and mechanical properties improved. Through a combination of grain-boundary, solid-solution, and precipitation strengthening, the cooling rate indirectly affected the mechanical properties of the heat-treated alloy sheets. The Al−4.5 wt% Cu alloy prepared by twin-roll casting under a cooling rate of 117.3 K s −1 exhibited a strength between 145.33 and 321.79 MPa and an elongation of 11.65%, demonstrating its potential as a high-performance aluminium alloy.