Method of measuring fuel particle distribution in nuclear fuel compacts

Purpose: To provide a convenient method for measuring fuel particle distribution that can be applied to the process inspection in the production of nuclear fuel compacts. Constitution: In a method of taking X-ray radiography or gamma-ray autoradiography for nuclear fuel compacts, scanning the same by a photometer and measuring uranium distribution in the fuel compact base on the changes in blackening, three or more compacts are disposed in adjacent to each other so that the direction for measuring the changes in the uranium content lie on a straight line. The surface of the compacts to be measured is contacted to a dummy compact. This can avoid the effects from X-ray scatterings in the periphery of the compacts. Opening of the window for the measurement of the blackening in the scanning direction is made smaller than the average inter-particle distance of the fuel particles in the graphite matrix and the opening in the direction perpendicular to the above direction is made greater than the average inter-particle distance. (Ikeda, J.)