Synthesis and Metallurgical Properties of Intermetallic Compounds.
Abstract
The connections between synthesis conditions, metallurgical properties and physical properties were investigated in the highest T sub C niobium based A-15 superconducting compounds. Thick chemically vapor deposited Nb3Ge deposits with T sub C up to 23.0 K were prepared using a new original vapor deposition apparatus. New results from closed tube iodide transport show that the range of compositions which 'Nb3Ga' exists extends from 75 at. % Nb to 90 at. % Nb, that is from Nb3Ga to Nb9Ga, a much broader range than was known. Iodide transport of Nb3Sn was successful in producing single crystals having resistance ratios as high as 20, more than a factor of two higher than previously reported. The low temperature resistivities of Nb3Ge, Nb3Al and Nb3Sn were found to follow a T2 law from T sub C to 40 K. Measurements on the effect of neutron damage induced disorder in Nb3Sn, Nb3Al and Nb3Ga were extended and in Nb3Al a large lattice parameter expansion with damage was found which could be related to site exchange disorder. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1975
- Accession Number
- ADA019558
Entities
People
- George W. Webb
- Gustaf Arrhenius
Organizations
- University of California, San Diego