The Paton Welding Journal, 2008, №02

2008 №02 (03)

2008 №02 (05)

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The Paton Welding Journal, 2008, #2, 19-21 pages

Reversible temper brittleness of welded joints of wwer reactor bodies

O.G. Kasatkin

E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.

Abstract
Reversible temper brittleness caused by an increased concentration of diffusible impurities, and phoshporus in particular, is the main reason of accelerated embrittlement of welded joints of a nuclear reactor body in the initial period of operation. Radiation defects of crystalline lattice caused by the neutron flux act as high-energy traps and decrease the concentration of the diffusible impurities. Increase in the fluence of fast neutrons leads to growth of the density of the crystalline lattice defects, which promote decrease in the concentration of impurities at grain boundaries, as well as decrease in temper brittleness.
Keywords: reactor body, welded joints, diffusion displacement of phosphorus, reversible temper brittleness, radiation defects, critical brittleness temperature

References

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Suggested Citation

O.G. Kasatkin (2008) Reversible temper brittleness of welded joints of wwer reactor bodies. The Paton Welding J., 02, 19-21.

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