期刊
ACTA MATERIALIA
卷 133, 期 -, 页码 380-392出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2017.04.072
关键词
Palladium nano polycrystalline; Structural defects; Static and dynamic structural disorder; Whole-powder-pattern-modelling; Debye-Waller parameter
资金
- Haydn Murray Applied Clay Mineralogy endowment, Indiana University
- Lilly Endowment, Inc.
Interacting distortion fields from local and diffuse structural defects in metal nanomaterials were investigated via atomistic simulations supported by X-ray powder diffraction (XRPD) analysis. Numerical models of several large nano polycrystalline Pd microstructures embedding a wide range of defect types and densities were equilibrated via molecular dynamics (MD) to evaluate the interaction effects of various structural defects on the deformation-field components. Microstrain contributions from crystallite grain boundaries (GBs), line dislocations, and vacancies were determined from analysis of line broadening in Debye-simulated XRPD profiles. Dynamic disorder was investigated across the crystallites, revealing anisotropic vibrational components of atoms at the GBs. Although the estimated structural and microstructural properties agreed globally with the ideally expected parameters directly calculated from numerical models, widely dispersed values were observed among the assemblage of crystallites. Estimated dynamic and static Debye-Waller parameters used to account, respectively, for atomic thermal vibration and disorder across the GBs were in excellent agreement with experimental values observed by Inagaki et al. (J. Mater. Sci, 18 (1983) 1803) for Pd metal powders. However, the static component decreased with environmental temperature and increasing interaction between defects in different crystallites, approaching zero in the limit. (C) 2017 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