Sodium corrosion and mass transfer analysis with an ion probe mass spectrometer

The initial application of ion probe mass spectrometry, a new analytical technique, to the characterization of samples from an experimental sodium mass transfer loop has been made. The technique is capable of performing multielement analyses from hydrogen to uranium at parts per million sensitivities with a spatial resolution of ∼1 μm. Analyses of hot leg samples from a 10 000 h/low oxygen loop reveal significant concentration changes over the depleted zone and confirm extensive loss of carbon. Analyses of cold leg deposits from the same loop show the presence of occluded metallic sodium and a small component of oxides, in addition to numerous other constituents. Concentration profiles in the deposits indicate that they are both nitrided and carburized with a major oxide layer in the interface between the deposits and the stainless-steel substrate.