The Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM) recently completed a Topical Safety Analysis Report (TSAR) for a Phase 1 non site specific Centralized Interim Storage Facility (CISF). The TSAR will be used in licensing the CISF when and if a site is designated. The combined Phase 1 and Phase 2 CISF will provide federal storage capability for 40,000 metric tons of uranium (MTU) Spent Nuclear Fuel (SNF) under the oversight of the DOE. The Phase 1 TSAR was submitted to the NRC on May 1, 1997 and is currently under review having been docketed on June 10, 1997. This paper generally describes the Phase 1 CISF design and its operations as presented in the CISF TSAR.

A unique roll forming technology that permits complex axisymmetric components, such as automobile wheels and turbine disks, to be formed in a single forming operation, has been developed by two Russian Institute, the Institute of Technical Physics of the Russian Federal Nuclear Center and the Institute for Metals Superplasticity Problems. This process was used to fabricate automobile wheels from a Russian AVT alloy, a 6010 aluminum alloy equivalent. The process included steps of isothermal roll forming of preforms into wheels shapes, all at 430C for the AVT alloy. The microstructure and mechanical properties were evaluated at various locations in the finished wheels by optical metallography and tensile testing at elevated temperatures. Tensile properties were obtained by stain-rate change tests and tensile tests to failure at high strain rates. Microstructure and mechanical propertied of the preforms and blanks were also evaluated. The results indicate that dynamically recovered microstructures were developed during the processing, which showed relatively high strain rate sensitivity and rendered sufficiently plasticity at the elevated temperature for wheel fabrication process.

Grain size distribution and its evolution during superplastic deformation has been studied for two materials- ultrahigh carbon steel, which has a two phase microstructure, and a copper alloy, which has a quasi-single phase microstructure. For both materials the distribution of initial grain size is very accurately represented by a lognormal throughout the deformation history. The evolution of the parameters characterizing the log normal distribution have also been studied and found to vary in a systematic manner results. Results can be used to specify the grain size distribution as a function of strain during superplastic deformation and thus should prove useful for computational studies in which grain size distribution is evaluated.