| Autor: |
H.W. Deng, H.E. Ge, C.Y. Zhan, Y. Liu, Q.S. Ren, Z.Y. Liu, T. Zhang |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Journal of Materials Research and Technology, Vol 24, Iss , Pp 9731-9742 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2023.05.173 |
| Popis: |
Tailoring the microstructure of metallic materials by controlling the fabrication process is crucial to achieving superior mechanical properties. Herein, the mechanism of modifying the microstructure and mechanical properties of medium-entropy CoCrNi alloys was investigated by equal-channel angular pressing (ECAP) at room temperature (RT) and cryogenic temperature (CT) and post-deformation annealing (PDA) and was analyzed by molecular dynamics simulations. It was found that temperature influences the deformation mechanism of the alloy, dislocations, stacking faults, deformation twins, and FCC-HCP phase transitions, which assume different roles at different temperatures. The dislocation density of the ECAP-CT sample is significantly higher than that of the ECAP-RT sample; however, the ECAP-RT sample exhibits unique deformation features of kink bands and hierarchical twin structure, resulting in dynamic grain refinement effects. In addition, the HCP phase strength increment caused by annealing-induced HCP phase transformation is higher in the ECAP-RT sample than in the ECAP-CT sample, thus leading to a substantial increase in strength after PDA. The present study exhibits the strengthening mechanisms and provides a generic approach to obtaining desirable mechanical properties of alloys. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
