Degradation of superconducting properties in MgB2 by formation of the MgB4 phase

YAKINCI M., BALCI Y., Aksan M. A., ADIGUZEL H. İ., GENCER A.

JOURNAL OF SUPERCONDUCTIVITY, cilt.15, sa.6, ss.607-611, 2002 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 15 Sayı: 6
  • Basım Tarihi: 2002
  • Doi Numarası: 10.1023/a:1021215728989
  • Dergi Adı: JOURNAL OF SUPERCONDUCTIVITY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.607-611
  • İnönü Üniversitesi Adresli: Evet

Özet

Superconducting MgB2 polycrystalline samples have been fabricated under two different conditions in order to determine the effect of MgB4 phase. A series of samples was placed in an alpha-alumina container closed with a cup and fired under high purity argon gas. The other series of samples was placed in an a-alumina boot without any lid and fired under similar conditions. For the first series of samples, we have found pure MgB2 phase formation and a narrow transition width at 0.4 K. For the second series of samples, significant amount of MgB4 phase were formed and the T-zero was decreased to 27 K. For both the group of samples magnetization hysteresis loops obtained at various temperature range and applied field up to 2 T. The best J(cmag) for the first series of samples was 1.9 x 10(5) x A/cm(2) at 10 K and 0 T, and for the second series of samples was 0.7 x 10(4) x A/cm(2) at 10 K and 0 T.