Accession Number : ADA296126

Title :   A Method for Simultaneously Enhancing the Transition Temperature and Increasing Mechanical Strength of Yttrium Barium Copper Oxide (YBa2Cu4O8).

Descriptive Note : Technical rept. Jun 92-May 94,

Corporate Author : ARMY RESEARCH LAB FORT MONMOUTH NJ

Personal Author(s) : Finnegan, Robert D. ; Tauber, Arthur ; Tidrow, Steven C. ; Wilber, William D. ; Leupold, Herbert A.

PDF Url : ADA296126

Report Date : APR 1995

Pagination or Media Count : 12

Abstract : Y124 can be heated to 850 deg C without serious O2 loss, and also Y123 loses O2 from its structure at temperatures above 400 deg C. Partial substitution of Ca for Y and of Li for Cu raised the transition temperature (Tc) and enhanced sintering in Y1Ba2Cu4O8. We measured the critical temperature by two methods; a microwave technique (RF) which measures the surface resistivity at 35 GHz, and an AC technique which measures the magnetic screening provided by the whole sample. Twelve samples of Y124 or Y1-zCazBa2Cu4-xLixO8 were prepared; a summary is presented. It is desirable to have a thin film of Y124 for device applications; we have not been successful at this endeavor. (AN)

Descriptors :   *TRANSITION TEMPERATURE, *HIGH TEMPERATURE SUPERCONDUCTORS, *YTTRIUM COMPOUNDS, *YTTRIUM, CALCIUM, MAGNETIC FIELDS, SYNTHESIS(CHEMISTRY), THIN FILMS, ALTERNATING CURRENT, STRENGTH(MECHANICS), CRITICAL TEMPERATURE, LITHIUM, COPPER COMPOUNDS, ELECTRICAL RESISTANCE, THERMAL STRESSES, SINTERING, POLYCRYSTALLINE, SUBSTITUTION REACTIONS, BARIUM OXIDES.

Subject Categories : Inorganic Chemistry
      Properties of Metals and Alloys
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE