Journal article
Additional grain boundary strengthening in length-scale architectured copper with ultrafine and coarse domains
Publication Details
Authors: | Hou, X.; Krauß, S.; Merle, B. |
Publisher: | PERGAMON-ELSEVIER SCIENCE LTD |
Publication year: | 2019 |
Journal: | Scripta Materialia |
Pages range : | 55-59 |
Volume number: | 165 |
Start page: | 55 |
End page: | 59 |
Number of pages: | 5 |
ISSN: | 1359-6462 |
DOI-Link der Erstveröffentlichung: |
Abstract
The strength of polycrystals is known to increase with decreasing grain size, known as Hall-Petch effect. However, this relationship fails to predict the strength of samples with a non-uniform distribution of grain sizes. In this study, we purposely designed and fabricated copper micropillars with a strongly bimodal microstructure: half volume consisted of a large number of ultrafine grains, while the other half was predominantly single-crystalline. Micropillar compression evidenced that bimodal samples are 35% stronger than their counterparts containing only ultrafine grains. This paradoxical finding highlights the greater strengthening potential of microstructure distribution engineering, compared to the traditional grain refinement strategy. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
The strength of polycrystals is known to increase with decreasing grain size, known as Hall-Petch effect. However, this relationship fails to predict the strength of samples with a non-uniform distribution of grain sizes. In this study, we purposely designed and fabricated copper micropillars with a strongly bimodal microstructure: half volume consisted of a large number of ultrafine grains, while the other half was predominantly single-crystalline. Micropillar compression evidenced that bimodal samples are 35% stronger than their counterparts containing only ultrafine grains. This paradoxical finding highlights the greater strengthening potential of microstructure distribution engineering, compared to the traditional grain refinement strategy. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Keywords
Bimodal grained microstructure, Crystal structure, Grain boundary strengthening, Hall-Petch effect, Mechanical property testing
