THE DETERMINATION OF ANTIMONY AND COBALT IN MAGNESIUM-BASE ALLOYS BY NEUTRON ACTIVATION ANALYSIS

A method is described for the determination of Sb and Co in Mg alloyed with small amounts of Al or Mn. The method involves remote irradiation in a nuclear reactor, radiochemical separation of the resulting Sb and Co activities, and comparison of these activities with those isolated from standards irradiated at the same time. The separation procedures are intended to be virtually specific, but not unreasonably time-consuming. It is shown that a hydrochloric acid/hydrogen-peroxide dissolution leads to no iosses of Sb as stibine, or of either element in the form of insolubles. It is also shown that chemical exchange between antimonyl tartrate and Sb present in chloride or suifate solution is slow, and the antimonyl tartrate standards must be fumed to destroy tartrate. Results for Sb and Co were obtained at levels down to 0.05 and 0.01 ppm, respectively, both being appreciably above the limit of detection. (auth)