Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys
The hardening effect caused by the relaxation of nonequilibrium grain boundary structure has been explored in nanocrystalline Ni–W alloys. First, the kinetics of relaxation hardening are studied, showing that higher annealing temperatures result in faster, more pronounced strengthening. Based on the...
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| Format: | Article |
| Language: | en_US |
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Cambridge University Press (Materials Research Society)
2013
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| Online Access: | http://hdl.handle.net/1721.1/79785 https://orcid.org/0000-0001-9856-2682 |
| _version_ | 1826206035745964032 |
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| author | Rupert, Timothy J. Trelewicz, Jason R. Schuh, Christopher A. |
| author2 | Massachusetts Institute of Technology. Department of Materials Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Materials Science and Engineering Rupert, Timothy J. Trelewicz, Jason R. Schuh, Christopher A. |
| author_sort | Rupert, Timothy J. |
| collection | MIT |
| description | The hardening effect caused by the relaxation of nonequilibrium grain boundary structure has been explored in nanocrystalline Ni–W alloys. First, the kinetics of relaxation hardening are studied, showing that higher annealing temperatures result in faster, more pronounced strengthening. Based on the temperature dependence of relaxation strengthening kinetics, triple junction diffusion is suggested as a plausible kinetic rate limiter for the removal of excess grain boundary defects in these materials. Second, the magnitude of relaxation strengthening is explored over a wide range of grain sizes spanning the Hall–Petch breakdown, with an apparent maximum hardening effect found at a grain size below 10 nm. The apparent activation volume for plastic deformation is unaffected by annealing for grain sizes down to ∼10 nm, but increases with annealing for the finest grain sizes, suggesting a change in the dominant deformation mechanism for these structures. |
| first_indexed | 2024-09-23T13:22:59Z |
| format | Article |
| id | mit-1721.1/79785 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:22:59Z |
| publishDate | 2013 |
| publisher | Cambridge University Press (Materials Research Society) |
| record_format | dspace |
| spelling | mit-1721.1/797852022-09-28T13:46:12Z Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys Rupert, Timothy J. Trelewicz, Jason R. Schuh, Christopher A. Massachusetts Institute of Technology. Department of Materials Science and Engineering Rupert, Timothy J. Trelewicz, Jason R. Schuh, Christopher A. The hardening effect caused by the relaxation of nonequilibrium grain boundary structure has been explored in nanocrystalline Ni–W alloys. First, the kinetics of relaxation hardening are studied, showing that higher annealing temperatures result in faster, more pronounced strengthening. Based on the temperature dependence of relaxation strengthening kinetics, triple junction diffusion is suggested as a plausible kinetic rate limiter for the removal of excess grain boundary defects in these materials. Second, the magnitude of relaxation strengthening is explored over a wide range of grain sizes spanning the Hall–Petch breakdown, with an apparent maximum hardening effect found at a grain size below 10 nm. The apparent activation volume for plastic deformation is unaffected by annealing for grain sizes down to ∼10 nm, but increases with annealing for the finest grain sizes, suggesting a change in the dominant deformation mechanism for these structures. United States. Army Research Office (Grant W911NF-09-1-0422) United States. Army Research Office (Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies) 2013-08-05T16:31:33Z 2013-08-05T16:31:33Z 2012-03 2011-10 Article http://purl.org/eprint/type/JournalArticle 0884-2914 2044-5326 http://hdl.handle.net/1721.1/79785 Rupert, Timothy J., Jason R. Trelewicz, and Christopher A. Schuh. “Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys.” Journal of Materials Research 27, no. 09 (May 14, 2012): 1285-1294. © Materials Research Society 2012 https://orcid.org/0000-0001-9856-2682 en_US http://dx.doi.org/10.1557/jmr.2012.55 Journal of Materials Research Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Cambridge University Press (Materials Research Society) MIT web domain |
| spellingShingle | Rupert, Timothy J. Trelewicz, Jason R. Schuh, Christopher A. Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title | Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title_full | Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title_fullStr | Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title_full_unstemmed | Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title_short | Grain boundary relaxation strengthening of nanocrystalline Ni–W alloys |
| title_sort | grain boundary relaxation strengthening of nanocrystalline ni w alloys |
| url | http://hdl.handle.net/1721.1/79785 https://orcid.org/0000-0001-9856-2682 |
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