University of North Texas Digital Library (University of North Texas) · 1988 · 12 citations · 0 references
Open access
EngineeringNuclear EngineeringPhysicsNuclear MaterialsNuclear PhysicsReactor PhysicsCreep BehaviorCreep DeformationRadiation Damage In MaterialsRadiation HardeningReactor KineticsThermal Reactor PhysicsIrradiation CreepNeutron Damage EffectsNeutron Flux EffectsNeutron IrradiationNeutron Irradiation DamageNeutron Irradiation EffectsRadiation-induced CreepTransient Thermal Stresses
High-temperature gas-cooled reactors (HTGR) have massive blocks of graphite with thermal and neutron-flux gradients causing high internal stresses. Thermal stresses are transient; however, stresses generated by differential growth due to neutron damage continue to increase with time. Fortunately, graphite also experiences creep under irradiation allowing relaxation of stresses to nominally safe levels. Because of complexity of irradiation creep experiments, data demonstrating this phenomenon are generally limited to fairly low fluences compared to the overall fluences expected in most reactors. Notable exceptions have been experiments at 300/degree/C and 500/degree/C run at Petten under tension and compression creep stresses to fluences greater than 4 /times/ 10/sup 26/ (E > 50 keV) neutrons/m/sup 2/. This study complements the previous results by extending the irradiation temperature to 900/degree/C. 2 refs., 3 figs.