Khalid Hamdi Razzeg¹, Sabah M. Ali Ridha², Chanar Abiden Zaynel¹

This research involved the preparation of samples of Bi_2-(x+y)Pb_xAg_y Sr₂Ca₂Cu₃O_10+δ compounds and with different concentration of (x,y) which are (x=y=0) (x=0.05,y=0.15) (x=y=0.1) (x=0.15, y=0.05) by the method of solid state reaction under hydrostatic pressure of 8 ton/cm² temperature of annealing 850 k to know the range of effect of partial substitution on the synthetic and electric properties of compound. After undergoing the test of x-ray diffraction, it looked like the best substitution ratio of pb and Ag in Bi is when (x=0.05,y=0.15 ) where the values of lattice dimensions were a=b=5.4056 c=37.4226 A^◦ and the crystalline composite is of tetragonal type this research also revealed that the oxygen has a vital role in increasing the critical temperature, we noticed by studying the electrical properties the critical temperature in this substitution Tc=143 k.

partial substitution, electrical properties, superconductor