期刊
ACTA MATERIALIA
卷 98, 期 -, 页码 29-42出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2015.07.016
关键词
Rene 88DT superalloy; Strain localization; High resolution SEM DIC; Plastic straining; Coherent twin boundary; In situ testing; Elastic anisotropy
资金
- GE Global Research
- Canadian NSERC discovery grant
- Quebec MDEIE PSR-SIIRI
Damage during cycling loading of polycrystalline metallic alloys involves localized plastic straining at the scale of individual grains. To better understand damage accumulation processes and to build models for material behavior there is a need for quantitative assessment of the heterogeneous strain fields at the grain and even more microscopic scales. In the present study, a digital image correlation (DIC) approach has been developed to measure the strains at the grain level and at finer scales where plastic strain localization is manifested as physical slip bands. Strain fields have been measured in situ and ex situ on a Rene 88DT polycrystalline nickel-based superalloy to assess the grain-scale deformation processes during monotonic straining in tension and compression. DIC analysis and transmission electron microscopy demonstrate that slip occurs in a highly localized manner. The highest localized strains developed in slip bands that formed on {1 1 1} planes parallel to, and slightly offset from, annealing twins. Enhanced local straining below yield was observed during compression loading. The degree of strain concentration caused by slip bands impinging on grain boundaries was also analyzed. The results are compared to predictions of plasticity models. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据