Investigation of irradiated metal of WWER-type reactor internals after 45 years of operation. Part 2. Calculated and experimental determination of the fast neutron fluence and damage dose

The paper presents the statistical analysis of experimental results of radiation-induced critical brittle temperature ΔTF shifts and reference temperatures ΔT0 obtained respectively from the impact bend and fracture toughness tests of the reactor vessel metal surveillance specimens to define the possibility of their mutual application for the irradiation embrittlement coefficient to be determined more accurately. The correlation between these parameters is shown to remain up to the accumulation of over-design fast neutron fluence.

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Experimental Determination of the Differential Fast-Neutron Flux in the High Flux Isotope Reactor Using Techniques Threshold Detectors

Nuclear Applications and Technology ◽

10.13182/nt70-a28677 ◽

1970 ◽

Vol 8 (3) ◽

pp. 296-301

Author(s):

H. L. Dodds ◽

P. F. Pasqua

Keyword(s):

Neutron Flux ◽

Experimental Determination ◽

Fast Neutron ◽

High Flux ◽

Fast Neutron Flux

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Uncertainty determination of fast neutron fluence onto the WWER pressure vessel metal surveillance specimens

Nuclear Physics and Atomic Energy ◽

10.15407/jnpae2021.01.042 ◽

2021 ◽

Vol 22 (1) ◽

pp. 42-47

Author(s):

O.M. Pugach ◽

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S.M. Pugach ◽

V.L. Diemokhin ◽

V.N. Bukanov ◽

...

Keyword(s):

Fast Neutron ◽

Pressure Vessel ◽

Neutron Fluence ◽

Neutron Transport ◽

Monte Carlo Code ◽

Neutron Fluences ◽

Surveillance Programs ◽

Surveillance Specimens ◽

Reactor Pressure

The standard surveillance programs of WWER reactors do not allow to measure the surveillance specimens irradiation conditions with the required accuracy. Therefore, the special methodology for the determination of the surveillance specimens irradiation conditions of the reactor pressure vessel metal has been developed by the specialists of the INR of NASU and is successfully applied. The developed methodology bases on the use of the Monte-Carlo code for neutron transport calculations to the surveillance specimens locations. The methodology improvement is described. The fundamentals of the calculation-experimental determination of the fast neutron fluences onto surveillance specimens and their uncertainties are presented.

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Weak Beam Imaging and Diffraction Studies of Stacking Faults in Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092918 ◽

1976 ◽

Vol 34 ◽

pp. 590-591

Author(s):

T. Y. Tan ◽

W. K. Tice

Keyword(s):

Fast Neutron ◽

Rapid Determination ◽

Stacking Faults ◽

Imaging Method ◽

Large Reduction ◽

Dislocation Loops ◽

Fringe Spacing ◽

Weak Beam ◽

Kinematical Theory

In studying ion implanted semiconductors and fast neutron irradiated metals, the need for characterizing small dislocation loops having diameters of a few hundred angstrom units usually arises. The weak beam imaging method is a powerful technique for analyzing these loops. Because of the large reduction in stacking fault (SF) fringe spacing at large sg, this method allows for a rapid determination of whether the loop is faulted, and, hence, whether it is a perfect or a Frank partial loop. This method was first used by Bicknell to image small faulted loops in boron implanted silicon. He explained the fringe spacing by kinematical theory, i.e., ≃l/(Sg) in the fault fringe in depth oscillation. The fault image contrast formation mechanism is, however, really more complicated.

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