METALLURGICAL QUARTERLY PROGRESS REPORT NO. 15 FOR THE PERIOD OF APRIL 1, 1962 THROUGH JUNE 30, 1962

Technical Report · Wed Oct 31 00:00:00 EST 1962

OSTI ID:4804656

The phase diagram of the V--Hf system is approaching completion; only the determinatibn of the V solvus remains. Melting points and a preliminary determination of phase boundaries, based on as-cast microstructure, were proposed for the Hf --Ir alloy system. Alloys of Dy, Er, Gd, and Sm, alloyed with Ca, Zr, V, Cr, Fe, Ni, Cu, and Al, were prepared and meiting points, transition temperatures, eutectic and compound compositions, solid solubilities and oxidation properties are being studied. Of special interest is the fact that rare-earth Cu alloys of equal atomic ratios can be cold worked. Tolerance limits for Oa, Na, and C were established in Nb--Ta welding. Pressure bonding appears to be the most satisfactory joining method. Preliminary studies of Hf --HfC systems indicate a phase diagram with peritectic and peritectoid reactions and limited C solid solubility. Techniques were devised for mixing, pre ssing, and sintering homogeneous compacts of Nb and Mo powder with 18% gadolinium oxide. In addition, prelfminary forging schedules were established and a cursory survey of tensile properties was completed. Binary alloys of Th with Ho, Nd, and Pr were prepared that contain from 10 to 50% of these rare earths. Variations in alpha-- beta transformation temperature, melting temperature, hardness, and recrystallization temperature were determined. Feasible small-scale procedures for electric resistance fusing and leaching that could be scaled up to commercial operations were developed for obtaining' high extractions of Zr--W fluorides from zircon. Hf-enriched liquors with Hf -- Zr ratios of about 6 were produce by single-stage fractional crystallization of Zr -- W fluorides in dilute acid solutions. Measurements of coolant flow, heat dissipation and wall thickness as they affect cold-mold arc melting are continuing. Purification mechanisms and the establishment of identities of evaporating species when metals are melted in an electron-beam furnace are continuing. In the case of Hf, most metallic impurities and H/sub 2/ are removed during the first few minutes of melting. Ci, N/sub 2/, and O/sub 2/, in this order, were eliminated at a slower rate. Al, Zr, and Hf oxides are evaporated as monoxide; Cu, Fe, Cr, Mg, and Ti oxide s tend to dissociate below the meiting point of Hf and are evaporated as either the suboxides or as metallics. Hf-C systems varying from 2.72 to 15.7% C were prepared and evaluated for the following properties as a function of C content: melting point, density, microhardness, electric resistance, oxidation rate, and lattice dimension. The preparation of suitable electrodes for successful consumable-electrode arc melting of UC has been a major problem. The most useful, but not completely satisfactory, electrodes were prepared by mixing fine U saw cuttings with C and pressing at about 30 tsi. Sidewall fusing was required to provide strength and electric conductivity. (auth)

• Research Organization: Bureau of Mines. Albany Metallurgy Research Center, Ore.
• DOE Contract Number: AT(11-1)-599
• NSA Number: NSA-16-029319
• OSTI ID: 4804656
• Report Number(s): USBM-U-952
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-62
• Country of Publication: United States
• Language: English

Related Subjects

METALS, CERAMICS, AND OTHER MATERIALS
ACIDS
ALLOYS
ALUMINUM ALLOYS
ALUMINUM OXIDES
BONDING
CALCIUM ALLOYS
CARBON
CHROMIUM ALLOYS
CHROMIUM OXIDES
COLD WORKING
COPPER ALLOYS
COPPER OXIDES
DECOMPOSITION
DENSITY
DYSPROSIUM COMPOUNDS
ELECTRIC ARCS
ELECTRIC CONDUCTIVITY
ELECTRODES
ELECTRON BEAMS
ENRICHMENT
ERBIUM COMPOUNDS
EUTECTICS
EVAPORATION
FORGING
FURNACES
FUSED SALTS
GADOLINIUM ALLOYS
GADOLINIUM OXIDES
HAFNIUM
HAFNIUM ALLOYS
HAFNIUM CARBIDES
HAFNIUM FLUORIDES
HAFNIUM OXIDES
HARDNESS
HEAT TRANSFER
HOLMIUM COMPOUNDS
HYDROGEN
IMPURITIES
IRIDIUM ALLOYS
IRON ALLOYS
IRON OXIDES
LATTICES
LEACHING
MAGNESIUM OXIDES
MEASURED VALUES
MELTING
MELT