Transmission electron microscopic study of grain boundaries in (Bi,Pb)2Sr2Ca2CuOχ silver-sheathed tapes

Abstract The grain boundaries in high- j c (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O χ silver-sheathed tapes have been investigated using transmission electron microscopy (TEM). Two basic types of boundaries have been observed. Both types permit the outstanding supercurrent transport over macroscopic distances. The observed grain boundaries are found to not be accompanied by amorphous material and intergranular phases, even when they are totally incoherent.