Fluctuation of point defect reactions observed during the growth of dislocation loops under electron irradiation

During in-situ radiation damage experiments aiming on the investigation of vacancy-migration properties interstitial-type dislocation loops are used as probes monitoring the development of the point defect concentrations. The temperature dependence of the loop-growth rate v is analyzed in terms of reaction-rate theory yielding information on the vacancy migration enthalpy. The relation between v and the point-defect production rate P provides a critical test of such a treatment since it is sensitive to the defect reactions which are dominant. If mutual recombination of vacancies and interstitials is the dominant reaction, vαP0.5 holds. If, however, annihilation of the defects at unsaturable sinks determines the concentrations, a linear relationship vαP is expected.Detailed studies in pure bcc-metals yielded vαPx with 0.7≾×≾1.0 showing that besides recombination of vacancies and interstitials annihilation at sinks plays an important role in the concentration development which has properly to be incorporated into the rate equations.

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Detection of Space- and Time-Wise Fluctuation of Point Defect Reactions by the Observation of Small Vacancy Clusters Under Electron Irradiation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.15-18.889 ◽

1987 ◽

Vol 15-18 ◽

pp. 889-894 ◽

Cited By ~ 15

Author(s):

Toshimasa Yoshiie ◽

Michio Kiritani

Keyword(s):

Point Defect ◽

Electron Irradiation ◽

Vacancy Clusters ◽

Space And Time ◽

Defect Reactions

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Point defect reactions in silicon studiedin situby high flux electron irradiation in high voltage transmission electron microscope

Materials Science and Technology ◽

10.1179/mst.1995.11.11.1194 ◽

1995 ◽

Vol 11 (11) ◽

pp. 1194-1202 ◽

Cited By ~ 8

Author(s):

J. Vanhellemont ◽

A. Romano-Rodríguez ◽

L. Fedina ◽

J. Van Landuyt ◽

A. Aseev

Keyword(s):

Electron Microscope ◽

Point Defect ◽

Transmission Electron Microscope ◽

High Voltage ◽

Electron Irradiation ◽

High Flux ◽

Transmission Electron ◽

Defect Reactions ◽

High Voltage Transmission

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Point Defect Absorption and Dislocation Loop Formation at Grain Boundaries in Hvem-Irradiated Zr and Its Alloys:1. Influence of Solute Addition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011862x ◽

1985 ◽

Vol 43 ◽

pp. 350-351

Author(s):

R.A. Herring ◽

M. Griffiths ◽

M.H Loretto ◽

R.E. Smallman

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Point Defect ◽

Reactor Core ◽

Solute Concentration ◽

Nuclear Industry ◽

Dislocation Loops ◽

Loop Formation ◽

Component Material ◽

Impurity Interaction

Because Zr is used in the nuclear industry to sheath fuel and as structural component material within the reactor core, it is important to understand Zr's point defect properties. In the present work point defect-impurity interaction has been assessed by measuring the influence of grain boundaries on the width of the zone denuded of dislocation loops in a series of irradiated Zr alloys. Electropolished Zr and its alloys have been irradiated using an AEI EM7 HVEM at 1 MeV, ∼675 K and ∼10-6 torr vacuum pressure. During some HVEM irradiations it has been seen that there is a difference in the loop nucleation and growth behaviour adjacent to the grain boundary as compared with the mid-grain region. The width of the region influenced by the presence of the grain boundary should be a function of the irradiation temperature, dose rate, solute concentration and crystallographic orientation.

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