About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Heterostructured and Gradient Materials (HGM IV): Tailoring Heterogeneity for Superior Properties
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Presentation Title |
Heterostructured Ultrafine-grained Metallic Materials with Enhanced Superplasticity and Superior Strength |
Author(s) |
Ruslan Z. Valiev, Maxim Murashkin, Nguyen Chinh |
On-Site Speaker (Planned) |
Ruslan Z. Valiev |
Abstract Scope |
Herein, the possibility of ultrafine-grained (UFG) materials to demonstrate superplasticity at unusually low temperatures maintaining its high-strength state is reported for the first time. The UFG structure with the segregation of alloying elements at grain boundaries has been formed a number of commercial Al alloys by using severe plastic deformation (SPD) techniques. The obtained heterostructured UFG alloys exhibited good thermostability when testing or annealing up to 170 °C. Deforming by tensile test at a strain rate of 10<sup>-4</sup> s<sup>-1</sup> and 10<sup>-3</sup> s<sup>-1</sup>, the elongation to failure at 120 and 170 °C exceeds 250% and 500%, respectively, whereas the strain rate sensitivity reaches 0.45, which is a typical value characterizing superplastic deformation. After superplastic deformation, the UFG alloy maintains up to 50% higher strength characteristics at RT than that after conventional heat treatment T6. The origin of such superior behavior of the UFG alloys resulting from GB segregations is discussed. |
Proceedings Inclusion? |
Planned: |