Elongate bismuth system superconductor having aligned 2212 phase

A method for forming a composite conductor having a silver sheath and a core of an aligned oxide superconductor of the approximate formula Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y where y is from 7.5 to 8.5, x is from 0.0 to 0.5, and L is a lanthanide where if L is yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, a equals zero and b equals 0.0 to 0.3, and where if L is lanthanum, praseodymium, and neodymium, b equals zero and a equals 0.0 to 0.3, comprising the steps in sequence of:

• forming a powder mixture comprised of a superconducting bismuth oxide compound having the approximate formula Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y where y is from 6.5 to 7.5, and L is a lanthanide where if L is yttrium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, a equals zero and b equals 0.0 to 0.3, and where if L is lanthanum, praseodymium, and neodymium, b equals zero and a equals 0.0 to 0.3, and sufficient calcium copper oxide to react with Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y to form Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y ;
• forming a body having a silver sheath and a core of the mixture;
• preheating the body to partially react the Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y superconducting bismuth oxide compound with the calcium copper oxide to partially form the Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y superconductor;
• deforming the body to align the unreacted Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y superconducting compound and the Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y superconductor so that the c-axis of the crystals of the unreacted Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y superconducting compound and the Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y superconductor crystal, is aligned normal to the length dimension of the body;
• and
• thereafter, subsequently reaction-sintering the body until all the unreacted aligned Bi.sub.2-x Pb.sub.x Sr.sub.2-(a+b) L.sub.a Ca.sub.b CuO.sub.y and calcium copper oxides present have been consumed to form the aligned Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y core oxide superconductor.