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in subjects: "Platinum Metal Alloys"  
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Itinerant f-electron behavior in Ce and U compounds

Description: The experimentally observed Fermi surface properties in URh/sub 3/, UIr/sub 3/, UGe/sub 3/, CeSn/sub 3/, CeB/sub 6/, U/sub 3/As/sub 4/, U/sub 3/P/sub 4/, and CeSb are reviewed. For the compounds with no magnetic order, band structure models of the Fermi surface geometry are confirmed and f-ligand hybridization is found to be dominant. For CeB/sub 6/, U/sub 3/As/sub 4/, and U/sub 3/P/sub 4/ the experiments show that both local moments and f hybridization are important. In CeSb new data can be ex… more
Date: April 1, 1985
Creator: Crabtree, G.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metallurgical and mechanical properties of thorium-doped Ir-0. 3% W alloys

Description: Metallurgical and mechanical properties of Ir-0.3% W alloys have been studied as a function of thorium concentration in the range 0 to 1000 ppM by weight. The solubility limit of thorium in Ir-0.3% W is below 30 ppM. Above this limit, the excess thorium reacts with iridium to form second-phase particles. Thorium additions raise the recrystallization temperature and effectively retard grain growth at high temperatures. Tensile tests at 650/sup 0/C show that the alloy without thorium additions (u… more
Date: April 1, 1980
Creator: Liu, C.T.; Inouye, H. & Schaffhauser, A.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The structure and properties of grain boundaries in B2 ordered alloys

Description: This report covers the period from April 1, 1989 to March 30, 1990. During this period further extrusions of fine-grained alloys of FeAl and NiAl with different aluminum contents were produced. Thus far, researchers have (1) completed room temperature mechanical testing which shows that the yield strength, {sigma}{sub y}, of FeAl shows a minimum near Fe-45Al while that for NiAl increases with increasing (nickel-rich) deviation from stoichiometry; (2) showed that the grain boundary strengthening… more
Date: April 16, 1990
Creator: Baker, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Operational readiness review plan for the radioisotope thermoelectric generator materials production tasks

Description: In October 1989, a US shuttle lifted off from Cape Kennedy carrying the spacecraft Galileo on its mission to Jupiter. In November 1990, a second spacecraft, Ulysses, will be launched from Cape Kennedy with a mission to study the polar regions of the sun. The prime source of power for both spacecraft is a series of radioisotope thermoelectric generators (RTGs), which use plutonium oxide (plutonia) as a heat source. Several of the key components in this power system are required to ensure the saf… more
Date: April 19, 1990
Creator: Cooper, R. H.; Martin, M. M.; Riggs, C. R.; Beatty, R. L.; Ohriner, E. K. & Escher, R. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

General-Purpose Heat Source Development: safety test program. Postimpact evaluation, Design Iteration Test 1

Description: The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of /sup 238/PuO/sub 2/ decay to thermoelectric elements. Because of the inevitable return of certain missions, the heat source must be designed and constructed to survive re-entry and Earth impact. The Design Iteration Test (DIT) series is part of an ongoing impact test program. The first DIT used a full GPHS module containing two graphite impact shells (GISs); each GIS contained two iridium (0.3 w… more
Date: April 1, 1984
Creator: Schonfeld, F.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron-beam welding of thorium-doped iridium alloy sheets. [Ir--0. 3% W 200 ppM Th-50 ppM Al]

Description: Modified iridium alloys containing 100 ppM Th were found to be very susceptible to hot-cracking during gas tungsten-arc and electron-beam welding. However, the electron-beam welding process showed greater promise of success in welding these alloys, in particular Ir--0.3% W doped with 200 ppM Th and 50 ppM Al. The weldability of this particular alloy was extremely sensitive to the welding parameters, such as beam focus condition and welding speed, and the resulting fusion zone structure. At low … more
Date: April 1, 1979
Creator: David, S.A.; Liu, C.T. & Hudson, J.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Compatibility of Pt-3008 with selected components of the selenide isotope generator system

Description: The first in a new generation of radioisotopic thermoelectric generators being built by Teledyne Energy Systems and designated the Selenide Isotope Generator has thermoelectric materials that can be degraded by reaction with O/sub 2/, H/sub 2/O, CO, and other gases. Consequently, for at least the first ground demonstration system a protective xenon atmosphere will be maintained over the thermoelectrics. The high-temperature portion of the atmosphere-retaining structure will be fabricated from t… more
Date: April 1, 1979
Creator: Keiser, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electronic structure of substitutionally disordered alloys: Direct configurational averaging

Description: The method of direct configurational averaging (DCA) has been proposed to study the electronic structure of disordered alloys. Local density of states and band structure energies are obtained by averaging over a small number of configrations within a tight-binding Hamiltonian. Effective cluster interactions, the driving quantities for ordering in solids, are computed for various alloys using a tight-binding form of the linearized muffin-tin orbital method (TB-LMTO). The DCA calculations are use… more
Date: April 1, 1992
Creator: Wolverton, C.; de Fontaine, D.; Dreysse, H. & Ceder, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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