Determination of impurities in technical cobalt by instrumental neutron activation analysis

Instrumental neutron activation techniques for the determination of 13 impurities with limit detection 0.1-100 mg/kg in technical cobalt have been developed using thermal and epithermal neutrons of a nuclear reactor. Self-shielding and disturbance of neutron flux (59Co has a high neutron capture cross-section) by a sample were taken into account by using some references and from the results obtained in preliminary experiments. Samples and standards have been arranged in such a way, that neutron flux disturbance was less than 2–3%. The Al−Pb−Cd−Cu filter was used for absorption of low-energy ψ-rays of 60mCo and 61Co.