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Study of deformation mechanisms of zinc bicrystals by thermal cycling (1963); Etude des mecanismes de deformation par cyclage thermique de bicristaux de zinc (1963)

Abstract

The thermal cycling of zinc bicrystals has been studied in order to precise the thermal cycling growth mechanism, proposed by Burke and TURKALO, specially the dependence of 'equi-cohesive' temperature of grains on their mutual orientation and the parameters of the thermal cycle. Dilatometric studies showed that a bicrystal had no equi-cohesive temperature and that the grain-boundary develops stress at all temperatures. The creep of single and bicrystal have been studied on a dilatometer with stress below the Yield-stress. At constant temperature secondary creep appears after a transient period, at cycled temperature creep stays transient for strains of about 10{sup -4} to 10{sup -3} when the crystal is plastically hard. Micrographic investigations show that grain-boundary migration accompanies the grain boundary shearing and that cycles produce a strong polygonisation, corroborating the fact that the grain boundary remains a stress-generator and that creep occurs in the volume of grains. The discussion of results shows that the transient creep of hard grain in a bicrystal makes the thermal cycling irreversible and allows on elongation at each cycle if that have the lower expansion coefficient. (author) [French] Le cyclage thermique de bicristaux de zinc a ete etudie pour preciser le mecanisme de la croissance au  More>>
Authors:
Mondon, J [1] 
  1. Commissariat a l'Energie Atomique, Fontenay-aux-Roses (France). Centre d'Etudes Nucleaires
Publication Date:
Jun 15, 1963
Product Type:
Thesis/Dissertation
Report Number:
CEA-R-2305
Resource Relation:
Other Information: TH: These ES-sciences physiques; 55 refs
Subject:
36 MATERIALS SCIENCE; BICRYSTALS; CREEP; DEFORMATION; GRAIN ORIENTATION; SHEAR PROPERTIES; TEMPERATURE DEPENDENCE; THERMAL CYCLING; THERMAL EXPANSION; ZINC
OSTI ID:
20808559
Research Organizations:
CEA Fontenay-aux-Roses, 92 (France); Faculte des Sciences de l'Universite de Paris, 75 (France)
Country of Origin:
France
Language:
French
Other Identifying Numbers:
TRN: FR06R2305110064
Availability:
Available from INIS in electronic form
Submitting Site:
FRN
Size:
56 pages
Announcement Date:
Dec 23, 2006

Citation Formats

Mondon, J. Study of deformation mechanisms of zinc bicrystals by thermal cycling (1963); Etude des mecanismes de deformation par cyclage thermique de bicristaux de zinc (1963). France: N. p., 1963. Web.
Mondon, J. Study of deformation mechanisms of zinc bicrystals by thermal cycling (1963); Etude des mecanismes de deformation par cyclage thermique de bicristaux de zinc (1963). France.
Mondon, J. 1963. "Study of deformation mechanisms of zinc bicrystals by thermal cycling (1963); Etude des mecanismes de deformation par cyclage thermique de bicristaux de zinc (1963)." France.
@misc{etde_20808559,
title = {Study of deformation mechanisms of zinc bicrystals by thermal cycling (1963); Etude des mecanismes de deformation par cyclage thermique de bicristaux de zinc (1963)}
author = {Mondon, J}
abstractNote = {The thermal cycling of zinc bicrystals has been studied in order to precise the thermal cycling growth mechanism, proposed by Burke and TURKALO, specially the dependence of 'equi-cohesive' temperature of grains on their mutual orientation and the parameters of the thermal cycle. Dilatometric studies showed that a bicrystal had no equi-cohesive temperature and that the grain-boundary develops stress at all temperatures. The creep of single and bicrystal have been studied on a dilatometer with stress below the Yield-stress. At constant temperature secondary creep appears after a transient period, at cycled temperature creep stays transient for strains of about 10{sup -4} to 10{sup -3} when the crystal is plastically hard. Micrographic investigations show that grain-boundary migration accompanies the grain boundary shearing and that cycles produce a strong polygonisation, corroborating the fact that the grain boundary remains a stress-generator and that creep occurs in the volume of grains. The discussion of results shows that the transient creep of hard grain in a bicrystal makes the thermal cycling irreversible and allows on elongation at each cycle if that have the lower expansion coefficient. (author) [French] Le cyclage thermique de bicristaux de zinc a ete etudie pour preciser le mecanisme de la croissance au cyclage thermique propose par BURKE et TURKALO, notamment la temperature d' 'equicohesion' des grains en fonction de leur orientation mutuelle et du regime de cyclage impose. Des essais dilatometriques ont montre qu'un bicristal ne presentait pas de temperature d'equicohesion et que le joint exercait des contraintes quelle que soit la temperature superieure du cycle. Le fluage de monocristaux et de bicristaux a ete etudie sur un dilatometre avec des contraintes inferieures a la limite elastique. A temperature constante le fluage secondaire apparait apres une periode transitoire, a temperature cyclee le fluage reste transitoire pour des deformations de l'ordre de 10{sup -4} a 10{sup -3} quand le cristal est plastiquement 'dur'. L'etude micrographique montre que la migration du joint accompagne le cisaillement intergranulaire et que le cyclage produit une forte polygonisation dans les grains, confirmant le fait que le joint exerce toujours des contraintes et qu'il se produit un fluage dans le volume des grains. La discussion des resultats montre que le fluage primaire du grain 'dur' d'un bicristal rend la deformation par cyclage irreversible et permet un allongement a chaque cycle si ce grain possede un coefficient de dilatation plus faible que l'autre. (auteur)}
place = {France}
year = {1963}
month = {Jun}
}