Abstract It has been known that metals of groups IV-B, V-B, and VI-B of the periodic table, namely chromium, hafnium, molybdenum, niobium, tantalum, titanium, tungsten, vanadium, and zirconium and alloys thereof can be electrodeposited as dense, structurally coherent plates from a solution of the refractory metal fluoride in a molten alkali-flouride mixture in which the concentration of oxygen is reduced to and maintained at the sufficiently low level. It is shown that niobium may be plated at a lower temperature and a higher rate when the oxygen concentration is reduced to lower levels than previously attainable. The concurrent steps of electrolysis is a carbon anode, and evacuation whereby gases released from the melt at the carbon are withdrawn are shown to prepare a salt bath, and to be usable concurrently with the plating of pure niobium at a cathode, the metal depleted from the melt being replenished from a body of nobium of lesser purity maintained at a potential intermediate the potentials of the carbon anode and the niobium cathode.
Inventors
👤 Douglas W. Townsend
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 15:20
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/66
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
178 words
Electroplating apparatus comprising: (a) a crucible for maintaining a melt consisting essentially of at least one fluoride selected from the group consisting of alkali metal fluorides and alkaline earth metals fluorides above its melting temperature; (b) said crucible being enclosed and adapted to sustain a vacuum over said melt; (c) an anode comprised essentially of carbon disposed within said crucible in contact with said melt; (d) a cathode consisting essentially of metal to be deposited within said crucible in contact with said melt; (e) first electrical means for maintaining a positive electrical potential of about 1 to 3 volts on said anode relative to said cathode; (f) control means providing a substantially constant potential difference between said anode and said cathode keeping said potential between 1 and 3 volts; (g) second electrical means for maintaining a negative electrical potential on said cathode relative to said anode, whereby said metal to be deposited is plated on said cathode; and (h) second control means to control said negative potential and to control the rate at which said metal is deposited.
Claim 2
Dependent Claim
178 words
Electroplating apparatus comprising: (a) a crucible for maintaining a melt consisting essentially of at least one fluoride selected from the group consisting of alkali metal fluorides and alkaline earth metals fluorides above its melting temperature; (b) said crucible being enclosed and adapted to sustain a vacuum over said melt; (c) an anode comprised essentially of carbon disposed within said crucible in contact with said melt; (d) a cathode consisting essentially of metal to be deposited within said crucible in contact with said melt; (e) first electrical means for maintaining a positive electrical potential of about 1 to 3 volts on said anode relative to said cathode; (f) control means providing a substantially constant potential difference between said anode and said cathode keeping said potential between 1 and 3 volts; (g) second electrical means for maintaining a negative electrical potential on said cathode relative to said anode, whereby said metal to be deposited is plated on said cathode; and (h) second control means to control said negative potential and to control the rate at which said metal is deposited.
Claim 3
Dependent Claim
14 words
Apparatus as defined by claim 1, wherein said metal to be deposited is niobium.