Neutron radiography applications and techniques at the Hot Fuel Examination Facility

Neutron radiography has been used extensively at the Hot Fuel Examination Facility (HFEF) to evaluate the performance of irradiated nuclear fuels and materials. This nondestructive technique has proved extremely valuable in determining the internal condition of fuel pins during various stages of their burnup lifetime. Such features as pellet separation, voids, bond-sodium level, fuel cracking, and fissile density variations are easily detected by means of neutron radiography. Neutron radiography is also performed on large specialized assemblies. These include complete fuel-bundle assemblies, safety-test loops, and test sections from very large-scale safety-test loops following severe in-reactor tests. The HFEF neutron radiography facility is being expanded to provide more versatility and to allow further development of advanced neutron radiography techniques. (Auth.)