Texturing of precursor Bi1,6Pb0.4Sr2Ca3Cu4Ox (2234) rods by resistive-heat floating-zone method

SUMMARY Texturing Of Precursor Bii.6Pbo.4Sr2Ca3Cu40x(2234) Rods By Resistive-Heat Floating-Zone Method A new system called "Resistive Heating Floating Zone" (RHFZ) was designed and manufactured in order to obtain superconducting samples from the amorphous rods. Bii.6Pbo.4Sr2Ca3Cu40x (2234) amorphous rods were converted to the superconducting state by means of this apparatus and than some the physical properties of the samples were examined. These experimental results indicate that the low temperature phase (Bi- 2212) was readily obtained from the starting composition of Bii.6Pbo.4Sr2Ca3Cu40x (2234). In order to improve the physical properties of superconductors, the influence of growth rate on their microstructure has been analyzed, and it was found that the ratio of superconducting phase of 2212 increased with the lowest growth rates which results the better grain alignment in samples. The magnetic behaviour of textured BSCCO was determined by measurements of resistivity, p, in an external magnetic field. The normalized resistance as a function of temperature and of applied field of samples was plotted and the low temperature peaks show the energy dissipation due to the flux flow within the grains at a given field. In addition, the activation energy, Uo, for thermally activated flux flow (TAFF) was estimated for samples from the slope of the Arrhenius plot of lnp versus 1/T. It was found that the activation energy of samples decreases with increasing magnetic field. Key Words: BSCCO (2234) rod, Resistive-Heat Floating-Zone (RHFZ) method, Texture, Magnetic behaviour, Activation energy. VII