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Su Q, Xu J, Li Y, Yoon JI, Shan D, Guo B, Kim HS. Microstructural Evolution and Mechanical Properties in Superlight Mg-Li Alloy Processed by High-Pressure Torsion. MATERIALS 2018; 11:ma11040598. [PMID: 29652807 PMCID: PMC5951482 DOI: 10.3390/ma11040598] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 03/29/2018] [Accepted: 04/03/2018] [Indexed: 11/16/2022]
Abstract
Microstructural evolution and mechanical properties of LZ91 Mg-Li alloy processed by high-pressure torsion (HPT) at an ambient temperature were researched in this paper. The microstructure analysis demonstrated that significant grain refinement was achieved after HPT processing with an average grain size reducing from 30 μm (the as-received condition) to approximately 230 nm through 10 turns. X-ray diffraction analysis revealed LZ91 alloy was consisted of α phase (hexagonal close-packed structure, hcp) and β phase (body-centered cubic structure, bcc) before and after HPT processing. The mean value of microhardness increased with the increasing number of HPT turns. This significantly increased hardness of specimens can be explained by Hall-Petch strengthening. Simultaneously, the distribution of microhardness along the specimens was different from other materials after HPT processing due to the different mechanical properties of two different phases. The mechanical properties of LZ91 alloy processed by HPT were assessed by the micro-tensile testing at 298, 373, 423, and 473 K. The results demonstrate that the ultra-fine grain LZ91 Mg-Li alloy exhibits excellent mechanical properties: tensile elongation is approximately 400% at 473 K with an initial strain rate of 1 × 10−2 s−1.
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Affiliation(s)
- Qian Su
- Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Jie Xu
- Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Yuqiao Li
- Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Jae Ik Yoon
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea.
| | - Debin Shan
- Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Bin Guo
- Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education, Harbin Institute of Technology, Harbin 150080, China.
- School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Hyoung Seop Kim
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea.
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Abstract
Recently nanocrystalline Al-Fe alloys produced by a vapor quench method have been reported. These alloys are supersaturated solid solution and exhibit high strength with good ductility. It is postulated that the high strength of the Al-Fe alloys could be achieved by both the nano-grained structures and the solid solution strengthening. The contribution to the yield strength due to both the grain size strengthening and the solid solution strengthening were analyzed from the experimental data. Then the contribution to the yield strength due to the solid solution strengthening was estimated from the misfit strain calculated from the first principles in order to compare with analytical results estimated from the experimental data.
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Belyakov A, Sakai T, Miura H, Tsuzaki K. Grain refinement in copper under large strain deformation. ACTA ACUST UNITED AC 2001. [DOI: 10.1080/01418610108216659] [Citation(s) in RCA: 163] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Vinogradov A, Nagasaki S, Patlan V, Kitagawa K, Kawazoe M. Fatigue properties of 5056 Al-Mg alloy produced by equal-channel angular pressing. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0965-9773(99)00392-x] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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