Superconducting critical temperatures, critical magnetic fields, lattice parameters, and chemical compositions of ''bulk'' pure and alloyed Nb/sub 3/Sn produced by the bronze process

Journal Article · Sat Feb 01 04:00:00 EST 1986 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.336607· OSTI ID:6449207

Suenaga, M; Welch, D O; Sabatini, R L; Kammerer, O F; Okuda, S

Superconducting critical temperatures T/sub c/ and magnetic fields H/sub c/2, lattice parameters a/sub 0/, and chemical compositions were measured for ''bulk'' layers (approx. 6 ..mu..m or greater) of ''pure'' and alloyed Nb/sub 3/Sn which were made by the bronze process. The values of T/sub c/, a/sub 0/, and the composition of pure Nb/sub 3/Sn layers were approx. 18 K, 0.52900 +- 0.00005 nm, and 25 +- 0.5 at. % Sn, respectively, independent of heat-treatment temperature (between 650--780/sup 0/C) and of the bronze composition, as long as the thickness of the layers was greater than approx. 6 ..mu..m. Small additions of Ti (approx. 1 at. %) or Ta (approx. 3 at. %) slightly increased the value of T/sub c/ (by approx.0.2--0.4 K) above that for pure Nb/sub 3/Sn. However, additions of larger amounts of these elements or addition of other transition elements (V, Zr, and Mo) significantly decreased T/sub c/. Also, small additions of these elements significantly increased H/sub c/2. Specifically, the largest values of H/sub c/2 (approx. 27 T at 4.2 K) were obtained for Nb/sub 3/Sn layers containing approx. 1.5 and approx. 4 at. % of Ti and Ta, respectively, compared with a value for the pure Nb/sub 3/Sn of 23.5 T at 4.2 K. The value of a/sub 0/ decreased with all of the alloying additions; these variations can be explained qualitatively by several models for the lattice parameter of A15 compounds, but none of them can quantitatively predict the variations.

• Research Organization: Division of Metallurgy and Materials Science, Brookhaven National Laboratory, Upton, New York 11973
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6449207
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 59:3; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
CHEMICAL COMPOSITION
CRITICAL FIELD
DATA
DIMENSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
EXPERIMENTAL DATA
IMPURITIES
INFORMATION
LATTICE PARAMETERS
MAGNETIC FIELDS
METALS
MOLYBDENUM
NIOBIUM ALLOYS
NIOBIUM BASE ALLOYS
NUMERICAL DATA
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
THICKNESS
TIN ALLOYS
TRANSITION ELEMENTS
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE
VANADIUM
VERY HIGH TEMPERATURE
ZIRCONIUM