Selection and evaluation of a new Pu density measurement fluid

This paper summarizes efforts leading to selection of a new fluid for the determination of the density of large Pu parts. Based on an extended literature search, perfluorotributylamine (CF3(CF2)3)3N, trade name FC-43) was chosen for an experimental study. Plutonium coupon corrosion studies were performed by exposing Pu to deaerated and aerated solutions and measuring corrosion rates gravimetrically. Samples of deaerated and aerated (FC-43) were also irradiated with 60Co gamma rays. The samples were extracted with NaOH and analyzed by Ion Chromatography (IC). In surface study experiments, Pu coupons were exposed to deaerated and aerated solutions of FC-43 and analyzed by X-ray photoelectron spectroscopy (XPS). The XPS data indicate that there is no detectable surface effect caused by the new fluid.