Material test reactor

A series of tests were performed at the AFC s National Reactor Testing Station in Idaho, starting in 1953. The reactor was situated outdoors, and was operated remotely. The core of the first version had fuel assembhes of aluminum and enriched uranium plates of the Materials Testing Reactor (MTR) type, installed in a water tank. One of the five control rods could be ejected downward and out of the core by spring action upon intermption of a magnet... 

Uranium-235 Enrichment. The enrichment of uranium is expressed as the weight percent of in uranium. For natural uranium the enrichment level is 0.72%. Many appHcations of uranium requite enrichment levels above 0.72%, such as nuclear reactor fuel (56,57). Normally for lightwater nuclear reactors (LWR), the 0.72% natural abundance of is enriched to 2—5% (9,58). There are special cases such as materials-testing reactors, high flux isotope reactors, compact naval reactors, or nuclear weapons where enrichment of 96—97% is used. 

Fermium was formally discovered in 1954 at the Nobel Institute for Physics in Stockholm. It was synthesized in 1952 in the Material Testing Reactor in Idaho, but the discovery was not announced. The new element was named in honor of Enrico Fermi. There is no commercial application of this element because its yield is in extremely minute quantities. It has been detected in debris from thermonuclear explosion. 

Americium was isolated first from plutonium, then from lanthanum and other impurities, by a combination of precipitation, solvent extraction, and ion exchange processes. Parallel with the separation, a vigorous program of research began. Beginning in 1950, a series of publications (1-24) on americium put into the world literature much of the classic chemistry of americium, including discussion of the hexavalent state, the soluble tetravalent state, oxidation potentials, disproportionation, the crystal structure(s) of the metal, and many compounds of americium. In particular, use of peroxydisulfate or ozone to oxidize americium to the (V) or (VI) states still provides the basis for americium removal from other elements. Irradiation of americium, first at Chalk River (Ontario, Canada) and later at the Materials Testing Reactor (Idaho), yielded curium for study. Indeed, the oxidation of americium and its separation from curium provided the clue utilized by others in a patented process for separation of americium from the rare earths. 

The Dounreay site was established as the site of the UK Fast Breeder Nuclear programme in 1955 and became operational in 1958. It accommodated three reactors, the Materials Test Reactor, (DMTR, 1958-1969), the Dounreay Fast Reactor (DFR, 1959-1977) and the Prototype Fast Reactor (PFR, 1974-1994). With all reactor operations now finished and the reactors already de-fuelled the site is undergoing active decommissioning which is planned to be completed by 2032. The Dounreay site has been cited by UKAEA as being the second biggest nuclear decommissioning challenge in the UK with similar liabilities to those at Sellafield but with smaller waste volumes. 

The specimens to be bombarded are placed in the center of a pile such as the Materials Testing Reactor" at Arco, Idaho, a model of which is shown here. 

A modification of the Redox process, the U-hexone process, was used at the Idaho Chemical Processing Plant of the U.S. AEC, to recover highly enriched uranium from U-A1 alloy fuel elements irradiated in the Materials Testing Reactor. The aluminum nitrate needed as salting agent was provided when the fuel was dissolved in nitric acid. The plutonium content of the fuel was too low to warrant recovery. Plutonium was made trivalent and inextractable before solvent extraction and thus routed to the aqueous high-level waste. 

Aluminum is used for low power, water-cooled research, training, and materials test reactors in which temperatures are below 100°C. 

The Eurochemic reprocessing plant, erected by a consortium of 13 European member states of the OECD/NEA, was in active operation between 1966 and 1974. During these campaigns, 181.5 tons of natural and slightly enriched uranium fuels and 30.6 tons of highly enriched aluminum alloy fuels from material testing reactors were reprocessed. 

The pneumatic rabbits provide the Materials Testing Reactor with facilities to irradiate small samples of material in the high-neutron fields of the reactor. The horizontal holes that constitute the pneuntatic rabbit facilities are HR-1, 2. 3, and 4- However, any beam hole can be adapted to provide additional shuttle facilities. Holes HR-3 and 4 are of 4 in. I.D. and extend inward only to the reactor tank. Holes HR 1 and 2, which are 1 in. in diameter, extend completely through the reactor and pass within 1 in. of the. active lattice (see Fig. 2.D). ... 

Thomas, T. H., Materials Testing Reactor Report on Thermal Column, ORNL CF-50-2 28, February 6, 1950. 

The first approach to the design of the biological shield of the Materials Testing Reactor was the comparison of the neutron and y-ray fluxes incident on... 

Briggs, R, B., Heat Production in the Bottom Thermal Shield of the Materials Testing Reactor, ORNL-CF-49-12-1, December 1, 1949. 

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