LASL Nb/sub 3/Ge conductor development. Sixteenth quarterly progress report, April 1-June 30, 1980

Technical Report · Mon Dec 01 04:00:00 EST 1980

DOI:https://doi.org/10.2172/6851876· OSTI ID:6851876

Maley, M P ^[1]

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1. comp.

The 16th quarterly progress report of the Los Alamos Scientific Laboratory program to develop Nb/sub 3/Ge as a superconductor with potential applications to power transmission lines cover the period April 1-June 30, 1980. During this quarter an attempt to test our first 1-m-long Nb/sub 3/Ge cable at Brookhaven National Laboratory was unsuccessful owing to leaks in the cryogenic system. The tests are now scheduled for early July. Investigations of the influence of additions of boron and gallium to Nb/sub 3/Ge on its superconducting properties have been completed. Gallium additions produce a small decrease in T/sub c/ (approx. 1.0 K) but do not appear to enhance H/sub c2/. A thermal stress analysis of the cooldown of our Nb/sub 3/Ge tapes from their deposition temperature has been completed. It appears that a large bending moment generated by differential thermal contraction between the Nb/sub 3/Ge coat and the copper substrate may be responsible for longitudinal edge cracks. The appendix describes one of the problems encountered in developing a superconductor from a copper strip coated with a thin layer of niobium-germanium (Nb/sub 3/Ge) polycrystals. The conductor was made with several thicknesses of coating, and the thick coatings developed a crack. A series of hand calculations was done to define the mechanisms involved and to try to quantify the stress levels above which the crack occurs.

• Research Organization: Los Alamos Scientific Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6851876
• Report Number(s): LA-8606-PR
• Country of Publication: United States
• Language: English

Related Subjects

200303* -- Power Transmission & Distribution-- Superconducting & Cryogenic Systems-- (-1989)
24 POWER TRANSMISSION AND DISTRIBUTION
ALLOYS
BORON
CABLES
CONDUCTOR DEVICES
ELECTRIC CABLES
ELECTRICAL EQUIPMENT
ELEMENTS
EQUIPMENT
GALLIUM ALLOYS
GERMANIUM ALLOYS
NIOBIUM ALLOYS
PERFORMANCE TESTING
POWER TRANSMISSION LINES
RESEARCH PROGRAMS
SEMIMETALS
STRESSES
SUPERCONDUCTING CABLES
TESTING
THERMAL STRESSES