Effect of operational conditions on mechanical properties of the vessel material for A-1 heavy water reactor

The studies into the changes of the mechanical properties along the length of the reactor vessels and channels under high neutron fluxes (the centre of the core) have been investigated. Thew welded joints and adjacent zones and base metal showed only insignificant changes of the properties measured. The results obtained indicate that the material of the A-1 heavy-water reactor vessel is practically stable at the operation temperature of 373K fo more than 2 year service and under fast neutron radiation doses up to 3x1025m-2