Premium
Dissociation of the 〈001〉 Dislocations and Their Interactions with Dislocation Loops in Tetragonal BaTiO 3
Author(s) -
Cheng ShunYu,
Ho NewJin,
Lu HongYang
Publication year - 2006
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2006.00914.x
Subject(s) - climb , dislocation , partial dislocations , materials science , tetragonal crystal system , dislocation creep , crystallography , condensed matter physics , transmission electron microscopy , dissociation (chemistry) , crystal structure , composite material , chemistry , nanotechnology , physics , thermodynamics
Dislocations in pressureless‐sintered BaTiO 3 ceramics have been analyzed using transmission electron microscopy. Subjected to effective sintering stresses, dislocations were generated and multiplied in plastically deformed BaTiO 3 crystals by the Frank–Read mechanism from both single‐ and double‐ended sources. This is represented by dislocations encompassing a series of square‐like borders that shared a common center. All border dislocations exhibited the characteristic scallop shape. True dislocation line directions ( u ) were determined by trace analysis and Burgers vectors ( b ) by contrast analysis for the dislocations dissociated from b =〈001〉 into two half‐partials following the type (I) reaction ofby climb on {001}. Dislocation interactions between the main dislocations created from plastic deformation and dislocation loops of b =〈100〉 or 〈110〉 forming condensation of intrinsic Schottky vacancies were also found to obey the type (IV) reaction of, the type (V) reactions of . Migrating dislocations and loops interacting mutually in several stages, illustrated schematically, before arriving at the configuration described by types (IV) and (V) were observed and discussed.