A Comprehensive Study of Radiation Defect Clusters in GaAs Structures after Neutron Irradiation

AbstractThe microstructure of the low activation F82H ferritic/martensitic steel, which is a candidate for future fusion reactor first wall, has been studied in order to determine the differences between 590 MeV proton irradiations and fission neutron irradiations. A range of doses and temperatures are investigated. The present work focuses on the microstructure of irradiation induced defect clusters for cases of proton irradiations to doses up to 1.7 dpa, and for neutron irradiation to a single dose of 2.5 dpa. The irradiation temperatures were 40°C and 250°C in the case of the proton irradiation and 250°C in the case of the neutron irradiation. In the case of the proton irradiation no defects are observed in the transmission electron microscope in the case of the 0.45 dpa dose, while they start to be clearly visible for doses higher than about 1.0 dpa. In the case of the neutron irradiation a high density of defects and small loops is evidenced. These preliminary results are presented here.

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Radiation Defect Study in the P-Type Copper Seleind

MRS Proceedings ◽

10.1557/proc-234-227 ◽

1991 ◽

Vol 234 ◽

Author(s):

N. D. Marchuk ◽

A. P. Dolgolenko

Keyword(s):

Fast Neutron ◽

Nuclear Reaction ◽

Radiation Defect ◽

Neutron Fluence ◽

Fast Neutrons ◽

Thermal Neutrons ◽

Reactor Irradiation ◽

Defect Clusters ◽

High Fluences ◽

P Type

ABSTRACTP-Cu2-δ Se(δ=0.025) samples, self-doped through a departure from the stoichiometry(po= 4.8·1020) and cadmium-doped up to a concentration po= 5.6·1020cm−3 were studied in the course of their irradiation in a reactor up to a fluance of -6·1020 n·cm−2 of fast neutrons at a temperature of -500-550° C. The dependence of the resistivity and thermo-emf on the fast neutron fluence is described in terms of the theory of effective medium and representation of defect clusters as dielectric inclusions in a conducting matrix of p-Cu2Se(Cd) and p-Cu2_δSe samples.Defect clusters of a mean radius of -27 Å are shown to appear not only because of scattering of the fast pile neutrons on copper and selenium atoms, but also due to a nuclear reaction 112Cd(n,γ)114Cd on thermal neutrons with an efficiency of 3.43 cm−1. Increase of the conductivity in the process of the reactor irradiation of p-Cu2-δSe at small fluences of fast neutrons and appearance of a whitish deposit of selenium on the surface of samples after high fluences of fast neutrons were observed.

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INFLUENCE OF INITIAL DISLOCATION STRUCTURE ON POINT AND MICROSCOPIC DEFECTS KINETIC UNDER IRRADIATION

Vestnik of Samara University Natural Science Series ◽

10.18287/2541-7525-2016-22-1-2-69-84 ◽

2017 ◽

Vol 22 (1-2) ◽

pp. 69-84

Author(s):

D. A. Kornilov ◽

V. M. Kosenkov ◽

P. P. Silantev

Keyword(s):

Neutron Irradiation ◽

Dislocation Structure ◽

Edge Dislocation ◽

Material Properties ◽

Radiation Defect ◽

Defect Concentration ◽

Dislocation Loops ◽

Quantitative Effect ◽

Radiation Swelling ◽

Edge Dislocations

This work is aimed for justification of quantitative effect of radiation defect concentration decreasing in materials depending on density of edge dislocation which are their outlet. The results of defect kinetics modeling with taking into account their recombination on dislocation loops, edge dislocations and pores are given. The summery of this work is useful in the frame of solving problem of decreasing radiation swelling and material properties degradation during neutron irradiation.

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