Neutron radiography for non-destructive testing

Neutron Radiography is similar to conventional radiography except that a beam of thermal neutrons is used to probe the specimen under test. A suitable converter screen converts the neutrons into photographically detectable radiation, which exposes an X-ray film to attenuation of neutrons and X-rays by materials are fundamentally different. This difference makes neutron radiography useful in some special and unusual inspection problems hitherto difficult with conventional techniques. The basic fundamentals, techniques, instrumentation, capabilities and limitations of neutron radiography are briefly reviewed and interesting applications in diverse fields such as nuclear, aerospace, ordnance, metallurgy, biology and medicine etc. are illustrated. (author)