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The effects of prior cold rolling of up to an 80 pct reduction in thickness on the sensitizationdesensitization behavior of Type AISI 304 stainless steel and its susceptibility to intergranular corrosion have been studied by electrochemical potentiokinetic reactivation (EPR) and Strauss-test methods.The results indicate that the prior deformation accelerated the sensitization as compared to the undeformed stainless steel. The deformed Type 304 stainless steel experienced desensitization at higher temperatures and times, and it was found to be enhanced by increased cold deformation. This could be attributed to the increased long-range chromium diffusion, possibly brought on by increasing pipe diffusion and vacancies. The role of the deformation-induced martensite (DIM) and texture, introduced by uniaxial cold rolling, on the sensitization-desensitization kinetics has also been discussed. This study could not reveal any systematic relationship between texture and the degree of sensitization (DOS) obtained. The effect of DIM on DOS seems to be pronounced at 500°C when the steel retained significant amounts of DIM; however, the retained DIM is insignificant at higher sensitization times and temperatures.

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Oxides such as CaO, ZnO, Fe203, and Zr02 were substituted for SiOz into a 14 Na20. 10 B203.76 SiO, (wt%) glass in proportion to their weight percent in PNL-7668 simulated nuclear waste glass. No correlation was found between the Na diffusion coefficient (DNa) in the bulk glass and sodium leaching in water for any of the iron-containing borosilicate glasses. Effective diffusion coefficients calculated from the sodium leach rates in deionized water were 500 to 2000 times larger than DNs. The experimental leaching data agreed with a diffusion-convection model where the convective term was a measured "phaseboundary" velocity moving into the glass.