Effect of sintering temperature on TC of Bi2Ba2Ca2 Cu3O7-δ (system 2223)


samples of high temperature superconductors"Bi2 Ba2 Ca2 Cu3 O7-δ" were prepared by solid state reaction method with different sintering temperature(i.e 790,830,860,890) C°.X-ray analysis techniques were used to examine the structure of the compound, the study showed ,that the sample prepared during sintering temperature at 860 ċ exhibite tetragonal phase with lattice parameter,(a=b=5.408A°,C=30.88A°)while the compound prepared at 890C,° exhibit a change of structure from (tetragonal to orthorhombic) phase this is due to decreasing in(C)axises and increasing in the other two axis's (a,b)and the value of lattice parameters were a=5.418A°,b=5.429A°,C =30.75A°Electric resistively method were used to determine the critical temperature(TC)of these compounds using liquid nitrogen cryostat the compounds prepared at [790,830,860 and 890]C,°. Showed(TC)values of[105, 115,135, and92]K respectively.The change in(TC) values can be explained on the basis that increasing the sintering temperature produces a more uniform crystal structure and an increased oxygen content in the compound.