Effect of precursor composition on textured crystal growth of Bi2212 bulks in high magnetic field: investigations on Pb substitution and Ag doping

A comparison experiment has been carried out to study texture development in pure, Pb-substituted and Ag-doped Bi2212 bulks prepared by magnetic melt processing (MMP). X-ray diffraction and magnetization measurements show that no texture can be developed in pure Bi2212 bulk in 9 T magnetic field while obvious texture has been obtained in the Pb-substituted and Ag-doped bulks. Ag doping is found especially helpful for improving grain alignment and density of Bi2212 bulk prepared by MMP. It is proposed that during the crystal growth of pure Bi2212 there exists an obstacle to texture development in MMP. Some changes in precursor composition can overcome this obstacle and attention should be paid to precursor composition to enhance texture development in Bi2212 prepared by MMP. (C) 2000 Published by Elsevier Science B.V.