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Slow strain rate tensile tests were conducted on Grade-2 and Grade-12 titanium in simulated rock salt brines at about 83 C. The Grade-12 titanium studied showed superior mechanical properties compared to Grade-2 titanium, which were presumably due to smaller grain size and the presence of alloying elements and beta phase. Although neither metal showed obvious indications of stress corrosion cracking (SCC), the total elongation and reduction in area values showed some decrease. At the edge of the fracture surfaces in Grade-12 titanium specimens, a shear lip region was observed, but it was not related to the observed loss in ductility. Optical and scanning electron microscopy (SEM) results are discussed to elucidate the fracture mechanism.

The growth of platinum particles supported on flat alumina substrates, at 900–1100°C. has been studied for particles ranging in size from 35–120 nm. While the observed kinetics of growth were found to be inconsistant with classical (LSW) coarsening models, a reasonable interpretation of the results was obtained from an analysis based on nucleation-inhibited coarsening models. Comparison of the present results with those of earlier studies on smaller particles at lower temperatures has pointed out certain discrepancies which suggest possible directions for improvement of the kinetic models.

The corrosion behavior of TiCode-12 (Ti-0.3 Mo-0.8 Ni) high level nuclear waste container alloy has been studied for a simulated WIPP brine at a temperature of 150°C or below. Crevice corrosion was identified as a potentially important failure mode for this material. Within a mechanical crevice, a thick oxide film was found and shown to be the rutile form of TiO2, with a trace of lower oxide also present. Acidic conditions were found to cause a breakdown of the passive oxide layer. Solution aeration and increased acidity accelerate the corrosion rate. In hydrogen embrittlement studies, it was found that hydrogen causes a significant decrease in the apparent stress intensity level in fracture mechanics samples. Hydride formation is thought to be responsible for crack initiation. Stress corrosion cracking under static loads was not observed. Attention has also been given to methods for extrapolating short term uniform corrosion rate data to extended times.