Structural state of the claddings of fuel elements of the BN-600 reactor prepared from cold-deformed 16Cr-15Ni-2Mo-2Mn-Ti-V-B steel: Study using the method of high-resolution neutron diffraction

The applicability of the method of high-resolution neutron diffraction for determining defects (dislocations) in the bulk of a material is shown based on the example of a standard sample of deformed copper. The structural state of several samples of fuel-element claddings made of cold-worked steel 16Cr-15Ni-2Mo-2Mn-Ti-V-B (grade ChS68-ID) used in the BN-600 reactor, which were prepared by two producers, i.e., at the PJSC Mashinostroitel'nyi Zavod (MSZ) and at the PJSC Pervoural'sk Novotrubnyi Zavod (PNTZ), have been investigated. The conclusion has been drawn that the claddings have a texture in which the crystallographic planes of grains are oriented along the axis of the shells. It has been shown that the main defects in these claddings are edge dislocations; their density has been determined.