Melt processing of Ba2CuO3: Textured precursor for the fabrication of HgBa2CuOy superconductor

A process for the fabrication of textured Ba2CuO3 material with a microstru cture similar to that of melt-processed YBa2Cu3Oy (Y123) superconductor is discussed, The Ba2CuO3 samples were melt processed with the intent to use t hem as textured precursors for processing of HgBa2CuOy superconductor. The microstructure formation of the Ba2CuO3 phase was studied by observing the samples being quenched from intermediate stages of a melt growth schedule. The microstructure of melt-processed Ba2CuO3 reveals randomly oriented larg e-sized grains, similar to that of melt textured Y123, Other important micr ostructural features observed were finely distributed properitectic BaO par ticles, the absence of the platelet gaps within the domains, and the presen ce of a different kind of twin structure. The conversion of melt textured B a2CuO3 into superconducting HgBa2CuOy phase by a two-step process is discus sed.