Study on trace impurity elements in highly purified iron and aluminum by neutron activation analysis

Activation analysis was carried out on the purified iron and aluminum to study the behavior of trace impurities on purification process, and to estimate the purity of the purified samples. Thermal neutrons with high Cd ratio through D2O column or graphite column were used for the activation of samples to reduce the interference effects by fast neutrons, the reactions, (n, p) or (n, a), from matrix elements. On the zone refined aluminum, the segregation of impurity elements was cleary observed. In the case of iron, decrease of impurity content was confirmed on superposing the various purification processes.