2013 Fiscal Year Final Research Report
Martensitic Transformation from nanocrystalline austenite
Project/Area Number |
24656440
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Single-year Grants |
Research Field |
Material processing/treatments
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Research Institution | Kyoto University |
Principal Investigator |
SHIBATA Akinobu 京都大学, 工学(系)研究科(研究院), 助教 (60451994)
|
Project Period (FY) |
2012-04-01 – 2014-03-31
|
Keywords | 金属材料 / マルテンサイト / ナノ組織 / 電子顕微鏡法 |
Research Abstract |
We fabricated austenite structures with grain sizes ranging from 34 um to 290 nm in an Fe-22Ni (wt%) alloy by electrodeposition and subsequent annealing, and investigated microstructure and crystallographic features of martensite transformed from nanocrystalline austenite. Typical lath martensite formed from the coarse-grained austenite with a mean grain size of 34 um. With decreasing the austenite grain size below 4.0 um, the morphology of martensite changed from lath to plate shapes. Through crystallographic orientation analysis, we found that several martensite plates formed within one austenite grain even when the austenite grain size was 290 nm. In addition, crystallographic features, such as variant selection, of martensite transformed from the nanocrystalline austenite were completely different from those of the typical plate-type martensite transformed from coarse-grained austenite.
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Research Products
(9 results)