Superconducting thin film niobium carbonitrides on carbon fibers

Conference · Thu Jan 01 04:00:00 EST 1976 · Appl. Polym. Symp.; (United States)

OSTI ID:7180067

Pike, G E; Pierson, H O; Mullendore, A W; Schirber, J E

The preparation and characteristics of a new superconducting wire material, consisting of a 7 ..mu..m carbon filament substrate thinly coated with niobium carbonitride, are reported. These filaments are coated (approximately 1000 at a time as a yarn) by a chemical vapor deposition (CVD) process in which the carbonitride is deposited as a compound. NbCl/sub 5/ is the source gas for Nb, either N/sub 2/, (CH/sub 3/)/sub 3/N, (CH/sub 3/)/sub 2/NH, or NH/sub 3/ is the source gas for N, and either CH/sub 4/ or the amines is the source gas for C. Equilibrium thermochemical calculations for the most important reactions were conducted for a range of temperatures. A review is also made of that part of the Nb--N--C phase diagram which pertains to superconducting compositions and the effect of composition on the superconducting transition temperature T/sub c/ is examined. Reaction temperatures between 600 and 1200/sup 0/C were used to produce carbonitrides with transition temperatures up to 16.9/sup 0/K. The effect of CVD parameters on T/sub c/, the width of the transition, and the coating grain size are discussed. It is found that increasing the CVD time or temperature tends to broaden the superconducting transition. Some evidence for slight reaction with the carbon substrate is found.

• Research Organization: Sandia Labs., Albuquerque, NM
• OSTI ID: 7180067
• Conference Information: Journal Name: Appl. Polym. Symp.; (United States) Journal Volume: 29
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
360301* -- Composite Materials-- Preparation & Fabrication-- (-1987)
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CARBIDES
CARBON
CARBON COMPOUNDS
CARBONITRIDES
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COMPOSITE MATERIALS
CRITICAL CURRENT
CURRENTS
DEPOSITION
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
ELEMENTS
FILAMENTS
NIOBIUM CARBIDES
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
NONMETALS
PHYSICAL PROPERTIES
PNICTIDES
PRODUCTION
SUPERCONDUCTING COMPOSITES
SUPERCONDUCTIVITY
SURFACE COATING
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE