GROWTH OF Bi-2223 PHASE FROM TEXTURED Bi-2212 PHASE SOLIDIFIED IN HIGH MAGNETIC FIELDS

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1) Effect of Ag_2O,MgO and B_2O_3 additions on microstructure and superconducting properties of Bi-2223 phase after solidification in high magnetic fields:5%MgO and 5%Ag_2O additions improved the texture of Bi-2223 phase slightly after solidification in high magnetic fields but B2O3 addition never improved. MgO addition also improved the Jc value estimated from ΔM of hysteresis loop measured by VSM.2) Texture and superconducting properties of Bi-2201 phase solidified in high magnetic fields:Non-stoichiometric Bi-2201 phase were solidified in a magnetic field of 1OT. A Large, well c-axis aligned Bi-22O1 phase was obtained. As for the anisotropy, Jc flowed perpendicular to the applied magnetic field is about 10 times larger than that flowed parallel to it. On the contrary, no texture was observed in the Bi-22O1 sample solidified without a magnetic field.3) Formation and texture of Bi-2223 phase during sintering in high magnetic fields:Samples were sintered in the temperature range from 835 to 86O℃ in a magnetic field of 10T. Texturing of Bi-2223 phase was improved with increasing sintering temperature up to 855℃, however the volume fraction of Bi-2223 phase decreased with increasing sintering temperature. No Bi-2223 phase was observed after sintering at 860℃ where the liquid phase existed, but only well-aligned Bi-2212 phase was obtained.