QUARTERLY METALLURGICAL PROGRESS REPORT NO. 18, FOR THE PERIOD JANUARY 1 TO MARCH 31, 1963

Technical Report · Thu Oct 31 04:00:00 EST 1963

OSTI ID:4721739

The phase relationships of dysprosium, erbium, gadolinium, and samarium- rich alloys of selected non-rare earth metals were summarized in the form of diagrams. Hot water testing of dysprosium, gadolinium. and their alloys indicated that aluminum additions increased the corrosion resistance of the rare earth metal. Investigation of samarium-rich alloys of magnesium indicated the presence of the compound SmMg and a eutectic or eutectoid. A tentative hafnium- iridium phase diagram which has four compounds, two eutectics, and one eutectoid was drawn. The composition limits of the carbide, HfC, in the hafniumcarbon system occur at 3.9 and 5.9 wt% carbon by using composition-parameter graphs. Metallographic data indicate that the limits were 4.0 and 6.7 wt% carbon, respectively. Melting temperature and hardness of thorium were lowered by additions of either cerium or lanthanum. An increase in oxidation rate at 600 l C was observed for thorium with additions of holmium. Pressed and sintered powder compacts of alloys of molybdenum or tungsten with gadolinium oxide were fabricated to plate and sheet in an attempt to produce specimens for determining the physical, mechanical, and chemical properties of such alloys. The tungsten-rare earth oxide mixtures containing 10, 20, and 30% each of samarium, erbium, or europium oxides were sintered in hydrogen at 1,500 l C for 8 hours. Diffusion reactions at 1,100 l C between pieces of niobium metal were inhibited when samarium was used as the plating metal; no visible effect on the reaction was noted when zinc, cobalt, molybdenum, or titanium was the plating metal; and an increased diffusion rate was noted when copper or silver was used as the plating metal. Welds in sheets of niobium 0.1 inch thick were brittle when the oxygen content was 640 ppm or greater with nitrogen at 220 ppm and carbon at 60 ppm. A segmented crucible is being fabricated that will allow more careful heat transfer measurements to be made. Attempts to remove residual oxygen from yttrium by adding small amounts of other elements which may getter the oxygen and then be removed by evaporation were not particularly successful. Manganese evaporated from titanium rather easily. Small amounts of carbon reduced the oxygen content of zirconium. Hafnium carbide castings poured in rotating molds had better surface detail, finer grain structure, and greater density than similar castings from static molds. (auth)

• Research Organization: Bureau of Mines, Albany Metallurgy Research Center, Ore.
• NSA Number: NSA-17-023876
• OSTI ID: 4721739
• Report Number(s): USBM-U-1031
• Country of Publication: United States
• Language: English

Related Subjects

ALUMINUM
BRITTLENESS
CARBON
CASTING
CERIUM ALLOYS
CHEMICAL REACTIONS
COATING
COBALT
CONFIGURATION
COPPER
CORROSION
CRUCIBLES
DENSITY
DIFFUSION
DYSPROSIUM
DYSPROSIUM ALLOYS
ERBIUM ALLOYS
ERBIUM OXIDES
EUROPIUM OXIDES
EUTECTICS
EVAPORATION
FABRICATION
GADOLINIUM
GADOLINIUM ALLOYS
GADOLINIUM OXIDES
HAFNIUM
HAFNIUM ALLOYS
HAFNIUM CARBIDES
HARDNESS
HEAT TRANSFER
HIGH TEMPERATURE
HOLMIUM ALLOYS
HYDROGEN
IMPURITIES
INHIBITION
INTERMETALLIC COMPOUNDS
IRIDIUM ALLOYS
LANTHANUM ALLOYS
MAGNESIUM ALLOYS
MANGANESE
MEASURED VALUES
MECHANICAL PROPERTIES
MELTING POINTS
METALLOGRAPHY
METALS, CERAMICS, AND OTHER MATERIALS
MOLYBDENUM
MOLYBDENUM ALLOYS
NI