Hierarchical structure in Al-Cu alloys to promote strength/ductility synergy. (September 2021)

• Record Type: Journal Article
• Authors: Wu, S.H.; Xue, H.; Yang, C.; Kuang, J.; Zhang, P.; Zhang, J.Y.; Li, Y.J.; Roven, Hans J.; Liu, G.; Sun, J.
• Is Part Of: Scripta materialia. Number 202(2021)
• Publication Date: 2021-09
• Subjects: Al-Cu alloy -- Ultrafine-grained -- Microalloying effect -- Mechanical properties -- Hierarchical microstructure; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2021.113996
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: Experimental evidence demonstrated that equal channel angular pressing (ECAP) at cryogenic temperature, in comparison with ECAP at room temperature, led to promoted strength-ductility synergy in an Al-2.5wt.%Cu alloy. The simultaneous improvement is related to microstructural hierarchy of multimodal grains, low angle grain boundaries, and inter/intragranular precipitates, which was tuned by aging treatment in match with the low-temperature ECAP. The artificial aging could maintain multimodal grain size distribution, introduce a large number of low angle grain boundaries and produce intragranular precipitates to improve strength/ductility. A minor 0.3wt.% Sc addition was effective in optimizing the precipitations and further boosting the strength/ductility combination. The underlying mechanisms for higher strength and greater ductility were rationalized in terms of the low-temperature ECAP. Graphical abstract: Image, graphical abstract