CHEMICAL-COMPOSITION AND MICROSTRUCTURE OF MAGNETICALLY MELT-TEXTUREDBI2SR2CA0.8DY0.2CU2O8-Y

Dysprosium-doped Bi-based 2212 materials have been synthesized in the presence of a magnetic field, applied perpendicularly to the lateral f ace of a cylinder, by a melt-textured growth process. Thick (well orie nted) layers of different chemical composition have been observed. A d ysprosium-doped 2212 phase (the expected D phase) and a dysprosium-fre e bismuth-rich and strontium-deficient 2212 phase have been found. It is argued that the latter is a so-called M phase. Other impurity phase s have been observed connected with both 2212-type layers. A novel asp ect of this work is the calcium solubility at the strontium site in th e 2201 structure, and inversely the strontium solubility at the calciu m site in the 8250 structure.