ANOMALIES OF THERMAL-EXPANSION IN AG DIFFUSION DOPED BIPBSRCACUO SUPERCONDUCTORS

ALTUNBAS M., DZHAFAROV T., KUCUKOMEROGLU T., KOPYA A., GORUR O.

PHYSICA C, cilt.249, ss.133-138, 1995 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 249
  • Basım Tarihi: 1995
  • Doi Numarası: 10.1016/0921-4534(95)00301-0
  • Dergi Adı: PHYSICA C
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.133-138
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

Thermal expansion of Ag-Bi1.6Pb0.4Sr2Ca2Cu3Ox structures was measured in the interval 20-830 degrees C using an inductive dilatometer. Two anomalies in the thermal-expansion curves of samples were discovered: a decrease in length Delta L/L on heating (740-810 degrees C) and an increase in Delta L/L on cooling (810-660 degrees C). Changes of composition, structure and electrical properties of Ag doped superconductor caused by heat treatments during thermal-expansion runs were examined using XRD, DTA, optical microscopy and resistivity measurements. A model explaining the observed results was discussed. Thermal-expansion coefficients of Ag doped and undoped BiPbSrCaCuO samples are 7.5 x 10(-6) K-1 (at 60-680 degrees C) and 6.4 x 10(-6)K(-1) (at 30-830 degrees C), respectively.