Effect of ECAE-processing on the thermo-mechanical behavior of Ti34 wt.%Nb0.14 wt.%O shape memory alloy
| Autor: | Joong-Keun Park, R. Arockiakumar, Sang-Beom Kim |
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| Rok vydání: | 2012 |
| Předmět: |
Materials science
Equal channel angular extrusion Mechanical Engineering Metallurgy chemistry.chemical_element Shape-memory alloy Condensed Matter Physics Oxygen Stress (mechanics) chemistry Mechanics of Materials Martensite Ultimate tensile strength General Materials Science Grain boundary Severe plastic deformation |
| Zdroj: | Materials Science and Engineering: A. 546:53-58 |
| ISSN: | 0921-5093 |
| DOI: | 10.1016/j.msea.2012.03.023 |
| Popis: | The effect of ECAE (equal channel angular extrusion)-processing on the thermo-mechanical behavior of Ti34 wt.%Nb0.14 wt.%O shape memory alloy was studied by measuring the tensile stress–strain curve at various temperatures and using DSC, X-ray diffraction, and TEM. An ultrafine (0.4 μm) grain structure was developed by severe plastic deformation and by the formation of alpha-particles on grain boundaries, which was facilitated by oxygen. Severe grain refinement led to a large decrease of Ms from 216 °C to 106 °C. Furthermore, the elimination of oxygen by α-particles led to an abrupt decrease of the stress for reorienting the martensite variants and to an increase in the transformation strain. Subsequent ω-aging treatment further stabilized the β-phase at room temperature, resulting in a superelastic property. |
| Databáze: | OpenAIRE |
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