High critical current densities in Bi(2223)/Ag tapes

Bi(2223)/Ag monofilamentary tapes have been characterized by measurements of jc vs. B and vs. theta , the angle between the applied magnetic field and the c axis. High degree of texturing, high density and Bi(2223) single phase conditions were found to be the major effects leading to high jc values. A further condition for reaching the highest jc values is a very low overall carbon content, the presence of carbon at the grain boundaries acting as a strong limiting factor. The highest value of jc in the present work is 4.104 A/cm2 at 77K,0T, corresponding to more than 2.105 A/cm2 at 4.2K,0T.