Full metadata record
DC Field | Value | Language |
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dc.contributor.author | 장재일 | - |
dc.date.accessioned | 2022-10-17T07:04:52Z | - |
dc.date.available | 2022-10-17T07:04:52Z | - |
dc.date.issued | 2021-01 | - |
dc.identifier.citation | ACTA MATERIALIA, v. 202, Page. 124-134 | en_US |
dc.identifier.issn | 1359-6454; 1873-2453 | en_US |
dc.identifier.uri | https://www.sciencedirect.com/science/article/pii/S1359645420308648?via%3Dihub | en_US |
dc.identifier.uri | https://repository.hanyang.ac.kr/handle/20.500.11754/175493 | - |
dc.description.abstract | Spherical tip nanoindentation experiments on two typical face-centered cubic high-entropy alloys (HEAs), CoCrFeNi and CoCrFeMnNi in as-solutionized and aged conditions were performed using tips of two different radii. Large datasets of the strength at the first pop-in were obtained and their statistical nature were analyzed to gain insights into the micromechanisms responsible for the onset of incipient plasticity in HEAs that are notionally monophasic. In all the cases examined, the probability density distributions were bimodal in nature. The deconvoluted distributions were utilized to estimate the activation volumes of the underlying deformation mechanisms. They show that when the probed material's volume is relatively small, heterogeneous dislocation nucleation aided by monovacancies occurs at lower indentation stresses; this followed by homogeneous dislocation nucleation at high loads, resulting in strengths corresponding to the theoretical strengths. When a substantially larger volume is sampled, by using a larger radius tip, either the preexisting dislocation mediated ones at low stresses or vacancy cluster /grain boundary aided heterogeneous dislocations nucleation at higher stresses become dominant. Increasing the chemical short-range order in the alloy via high temperature aging leads to overall strengthening of the alloy by enhancing stress required for the homogeneous dislocation nucleation. Implications of such plurality of mechanisms with overlapping strength distributions at HEA's disposal in imparting high strength-ductility combinations are discussed. | en_US |
dc.description.sponsorship | We thank Dr. Jin-Yoo Suh of Korea Institute of Science and Technology for providing the specimens and Shankha Nag of École polytechnique fédérale de Lausanne for the discussion on statistical analysis. The work at Nanyang Technological University was supported by the funding from A*STAR via the Structural Metals and Alloys Programme (No. A18B1b0061). The work at Hanyang University was supported by the National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT) (No. 2020R1A2B5B01001446 and No. 2020R1A5A6017701). | en_US |
dc.language.iso | en | en_US |
dc.publisher | PERGAMON-ELSEVIER SCIENCE LTD | en_US |
dc.subject | High-entropy alloy; nanoindentation; pop-in; statistical analysis; short-range ordering | en_US |
dc.title | Bimodality of incipient plastic strength in face-centered cubic high-entropy alloys | en_US |
dc.type | Article | en_US |
dc.relation.volume | 202 | - |
dc.identifier.doi | 10.1016/j.actamat.2020.10.066 | en_US |
dc.relation.page | 124-134 | - |
dc.relation.journal | ACTA MATERIALIA | - |
dc.contributor.googleauthor | Zhao, Yakai | - |
dc.contributor.googleauthor | Park, Jeong-Min | - |
dc.contributor.googleauthor | Jang, Jae-il | - |
dc.contributor.googleauthor | Ramamurty, Upadrasta | - |
dc.relation.code | 2021006820 | - |
dc.sector.campus | S | - |
dc.sector.daehak | COLLEGE OF ENGINEERING[S] | - |
dc.sector.department | SCHOOL OF MATERIALS SCIENCE AND ENGINEERING | - |
dc.identifier.pid | jijang | - |
dc.identifier.researcherID | A-3486-2011 | - |
dc.identifier.orcid | https://orcid.org/0000-0003-4526-5355 | - |
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