Analysis and Characterization on Dynamic Recrystallization in Casting AZ31 Mg Alloys Under Plane Strain Compression
| Autor: | Jun Wang, Li Xu, Chao Xie, Jun Zhang, Minghua Xiang, Chenning Wang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
twinning Flow stress lcsh:Technology Article dynamic recrystallization Formability General Materials Science mg alloy Composite material lcsh:Microscopy Mg alloy strain rate temperature Stress concentration lcsh:QC120-168.85 lcsh:QH201-278.5 lcsh:T Recrystallization (metallurgy) Strain rate lcsh:TA1-2040 Dynamic recrystallization lcsh:Descriptive and experimental mechanics lcsh:Electrical engineering. Electronics. Nuclear engineering Severe plastic deformation Crystal twinning lcsh:Engineering (General). Civil engineering (General) lcsh:TK1-9971 |
| Zdroj: | Materials; Volume 13; Issue 3; Pages: 522 Materials, Vol 13, Iss 3, p 522 (2020) Materials |
| ISSN: | 1996-1944 |
| DOI: | 10.3390/ma13030522 |
| Popis: | Studies on twinning, twin-induced dynamic recrystallization (TDRX), and their temperature and strain rate dependences are of considerable significance to the ultimate strength and plastic formability of the coarse-grained Mg alloys during severe plastic deformation. Plane strain compression tests were conducted on the parallelepiped samples of casting AZ31 Mg alloys. The twinning and recrystallization behaviors close to and away from the crack boundaries were characterized using electron backscatter diffraction. The results show: (1) with increasing strain rate for tests, the extension twin proliferates significantly. Due to the local stress concentration, the TDRX is more active in the area close to the crack tip and exhibits the positive strain-rate sensitivity as twinning; (2) the TDRX is not only stress-favored but also closely links to the temperature. However, the TDRX is not utterly proportional to the temperature. Compared to 400 °C, 300 °C is more beneficial to the TDRX, achieving the higher strength and plastic deformability. The main reason is that the higher strain-hardening rate and flow stress at the higher strain rate and lower temperature motivates the transformation from twinning to the fine twin-walled grains more efficiently, and the stress-favored TDRX is crucial to refine grains and continue plastic deformation for the casting Mg alloys with coarse grains. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|