In this study, sintered bodies of TiO 2 nanopowders were fabricated by the combined application of magnetic pulsed compaction (MPC) and subsequent sintering and then, their density and shrinkage were investigated. The optimum mixing conditions of polyvinyl alcohol, water, and TiO 2 nanopowder for compaction were found to be 2-3 mass% PVA, 15-20 mass% water, and 70-85 mass% of TiO 2 powder in the sintered bulks. High pressure and rapid compaction using magnetic pulsed compaction (MPC) enhanced the density with the increasing MPC pressure up to 0.7 GPa and significantly reduced the shrinkage rate (about 15% in this case) of the sintered bulks compared to the general process (about 18%).
In this study, the effects of precompaction on the density, microstructure, mechanical and electrical properties of -Al 2 O 3 bulks fabricated by the combined application of magnetic pulsed compaction (MPC) and a sintering process were reported. The obtained density of the -Al 2 O 3 bulks prepared by the combined processes increased with the increasing MPC pressure and precompaction pressure. The resultant higher hardness and breakdown voltage of the consolidated bulks following combined application of the magnetic pulsed compaction, precompaction and sintering process could be attributed to the homogeneously distributed ultra-fine microstructure than that of general processing, suggesting that the grain growth was remarkably reduced during the MPC processes.
Leaching experiments on a simulated borosilicate waste glass were performed using a static method in the presence of PbO and bentonite. Ions in leachates were analyzed by ICP, while leached samples were characterized by several surface analytical methods such as XPS, SEM, EPMA, XRD and topography. As the simulated waste glass was leached in the presence of PbO and bentomte, lead hydroxide and insoluble elements (Ti, Nd, Ru and Zr ) were detected on the surface, respectively. On the other hand, a large amount of uranyl hydroxide was found on the surface of it when the borosilicate glass with 25 % U308 was leached in a soxhlet apparatus.Keywords simulated borosilicate waste glass, leach, surface analysis Borosilicate glass has been assessed as one of the best matrix materials for the immobilization of high level nuclear wastes. In order to isolate the radioactive waste safely from the biosphere for more than several thousands years, many environmental factors such as ground water, filler, metal barrier, buffer material, backfill material and rock should be considered in the leaching process of a borosilicate waste glass.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.