Positron annihilation in vacancies at grain boundaries in metals

被引：9

作者：

Kuriplach, J. ^{[1
]}

Melikhova, O. ^{[1
,2
]}

Hou, M. ^{[2
]}

Van Petegem, S. ^{[3
]}

Zhurkin, E. ^{[4
]}

Sob, M. ^{[5
,6
]}

机构：

[1] Charles Univ Prague, Fac Math & Phys, Dept Low Temp Phys, CZ-18000 Prague 8, Czech Republic

[2] Univ Libre Bruxelles, B-1050 Brussels, Belgium

[3] Paul Scherrer Inst, CH-5232 Villigen, Switzerland

[4] St Petersburg State Polytech Univ, Dept Expt Nucl Phys, St Petersburg 195251, Russia

[5] Masaryk Univ, Fac Sci, Dept Chem, CZ-61137 Brno, Czech Republic

[6] Acad Sci Czech Republic, Inst Phys Mat, VVI, CZ-61662 Brno, Czech Republic

来源：

APPLIED SURFACE SCIENCE | 2008年 / 255卷 / 01期

关键词：

positron annihilation; positron trapping at grain boundaries; vacancies; positron lifetime; molecular dynamics; atomic superposition method;

D O I：

10.1016/j.apsusc.2008.05.199

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The behavior of vacancies in selected coherent grain boundaries (GBs) in Fe and Ni is studied by means of molecular dynamics simulations. Corresponding positron lifetimes are calculated using the atomic superposition method. There is a difference between the vacancy behavior in Fe and Ni in dependence on temperature. In Ni, vacancies at GBs appear to diminish substantially their free volume (and lifetime) with the increasing temperature, which can be attributed to 'vacancy delocalization'. Contrary, GB vacancies remain stable up to apparently higher temperatures in Fe. (C) 2008 Elsevier B.V. All rights reserved.

引用

页码：128 / 131

页数：4

共 21 条

[1] Grain boundary sliding and migration: Effect of temperature and vacancies [J].