A REVIEW OF THE EFFECTS OF STARTING MATERIAL ON THE PROCESSING AND PROPERTIES OF TUNGSTEN, MOLYBDENUM, COLUMBIUM, AND TANTALUM

Technical Report · Mon Mar 13 04:00:00 EST 1961

OSTI ID:4051250

Allen, B C

Recent information is reviewed which relates characteristics of the as- reduced refractory metal powders to the properties of the conaolidated or fabricated product. The major impurities in these metals and their alloys are interstitials (C, 0, N, and H), which make up approximately 1/2 of the total impurity content; however, these impurities and the more volatile metallic impurities are largely removed by consolidation via powder metallurgy, arc melting, or electronbeam refining. For W, control over powder size is important for proper compacting and sintering to permit direct working or arc melting. If Mo is hydrogen-reduced from ammonium molybdate or paramolybdate, a uniformly pure product is obtained, while erratic material containing objectionable metallics can result if molybdic oxide is used. Because Ta and Nb are soft and ductile, the purity and particle size of the raw powders have a minor effect on subsequent properties. (41 references). (D.L.C.)

• Research Organization: Battelle Memorial Inst. Defense Metals Information Center, Columbus, Ohio
• NSA Number: NSA-15-014706
• OSTI ID: 4051250
• Report Number(s): DMIC-Memo-90; PB-161240
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALLOYS
AMMONIUM COMPOUNDS
BEAMS
CARBON
COMPACTING
CONTROL
DUCTILITY
ELECTRIC ARCS
ELECTRONS
FABRICATION
GRAIN SIZE
HYDROGEN
IMPURITIES
MELTING
METALS
METALS, CERAMICS, AND OTHER MATERIALS
MOLYBDENUM
MOLYBDENUM OXIDES
NIOBIUM
NITROGEN
OXYGEN
PARTICLES
POWDER METALLURGY
REFINING
REFRACTORIES
SINTERING
TANTALUM
TUNGSTEN
USES
VOLATILITY