Studying the radiation-induced changes in the form of hexagonal Shroud for the BOR-60 reactor materials testing assembly

Technique and investigation results of radiation-induced changes in the form of the shroud for the BOR-60 reactor experimental assembly are considered. The shroud studied is made of the OKh16N15M3B steel. Stress is developed by helium inside pressure. The shroud has been irradiated in the BOR-60 reactor to the maximum neutron fluence of 6.2x1026 m-2 (En>0.1 MeV). The cell, where irradiation was carried out, is placed on the boundary between the core and a radial shield, where the maximum radial gradient of neutron flux density is formed. During visual inspection appreciable shroud bending and buckling are not detected. Measurements have shown that maximum increase in actual size is approximately 1.4 mm. The conclusion is made that the calculation results for a radiation creep modulus of the material tested, carried out using the data obtained agree well with the values for steel 316 published earlier