Accession Number : ADA229845


Title :   Processing of Mixed Oxide Superconductors


Descriptive Note : Final rept. Dec 1987-Jul 1990,


Corporate Author : CAMBRIDGE UNIV (UNITED KINGDOM)


Personal Author(s) : Campbell, A M ; Ashby, M F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a229845.pdf


Report Date : Jul 1990


Pagination or Media Count : 74


Abstract : This work was initiated soon after the discovery of high temperature superconductors. Although much effort was being put into the research for higher temperature materials, it rapidly became clear that the main obstacle to the application of these materials was the low critical current density. Although in conventional materials the critical current density was determined by the pinning of flux lines by defects in the microstructure in high Tc materials, the appearance of weak links, or Josephson Junctions, at grain boundaries was the dominant effect. This was a completely new phenomena and led not only to rather low critical current densities in zero field but to a catastrophic drop in fields of only a few millitesla, although the upper critical field of these materials is extremely high (probably greater than 150 Tesla). The work can be divided into four main sections. These are magnetic separation, levitation, screening, and critical current studies.(ttl)


Descriptors :   *CURRENT DENSITY , *OXIDES , *SUPERCONDUCTORS , HIGH TEMPERATURE , JOSEPHSON JUNCTIONS , GRAIN BOUNDARIES , MAGNETIC SEPARATION , TEMPERATURE , LOW DENSITY , MATERIALS , MICROSTRUCTURE , MIXING


Subject Categories : Ceramics, Refractories and Glass
      Electricity and Magnetism
      Solid State Physics


Distribution Statement : APPROVED FOR PUBLIC RELEASE