ASSESSMENT OF IMPACTING THE THIN PROTECTIVE COATINGS ON THE STRESS-STRAIN STATE OF THE CLADDING OF FUEL RODS OF NUCLEAR REACTORS

It is proposed the approach for estimating the impact of thin protective coatings on the stress-strain state of the thick-walled claddings of cylindrical fuel rods considering internal and external pressures from fission products and moving heat carrier in a nuclear reactor core. This approach is used for quantitative estimations the impact of possible thin coatings made from a stainless steel on the stress-strain state of the cladding made from the Zirconium-based alloy used in the WWER-1000 nuclear reactors. It is shown that thin protective coatings can allow increasing the general strength and reliability of the cladding due to stresses decreasing.