Radiation embrittlement annealing

Regarding the neutron fluence value at the time of annealing, no substantial effects were found. Residual embrittlement, as well as the rate of further re-embrittlement, is practically independent of this neutron fluence. The lateral (horizontal) shift approach was also confirmed in the IAEA Round Robin Exercise on radiation embrittlement of WWER-440 weld metal, as shown in Rg. 5.16. The microstructure investigation results demonstrate that copper clusters, which are formed in material under primary irradiation, are not recovered during annealing to a structure of solid solution such as that in the unirradiated state. 

A. Amyev, A. Krynkov, M. Sokolov, Recovery of Transition Temperature of VVER RPV by Annealing, Steele L. E. (ed.). Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels An International Review (Fourth Volume), ASTM STP1170, American Society for Testing and Materials, Philadelphia, PA, pp. 369-379,1993. 

Six containers are designed for determination of radiation damage and two containers are planned to monitor potential vessel annealing, as well as further re-embrittlement if necessary. 

Aged to 1%, irradiated to 10 20% of mission life Comparing annealed to aged to irradiated Tensile testing - total elongation Mo-Re alloys exhibit radiation-induced embrittlement... 

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