Burnable neutron absorbers

摘要

A neutron-absorber body for use in burnable poison rods in a nuclear reactor. The body is composed of a matrix of Al2O3 containing B4C, the neutron absorber. Areas of high density polycrystalline Al2O3 particles are predominantly encircled by pores in some of which there are B4C particles. This body is produced by initially spray drying a slurry of Al2O3 powder to which a binder has been added. The powder of agglomerated spheres of the Al2O3 with the binder are dry mixed with B4C powder. The mixed powder is formed into a green body by isostatic pressure and the green body is sintered. The sintered body is processed to form the neutron-absorber body. In this case the B4C particles are separate from the spheres resulting from the spray drying instead of being embedded in the sphere.