Superconducting fibres of Bi(Pbflr-Ca4u-O hlgh T, superconducting materials have been prepared by means of the laser-healed pedestal growth ( L ~P G ) meinod. ine nignesi zero resisiance iempwrniure 7,, rwdchwa is i i l ii. and ?ne hignest critical current density J,(77 K. 0 T) is greater than 5000 A cm-'. As-grown superconducting fibres were successfully fabricated without post-growth heat treatment. Amorphous materials were used for t h e first time to make high quality fibres. The strong textured structure and highly aligned morphology of the fibres were studied. T h e influence of growth conditions. thermal treatment and the composition 01 the fibres was also discussed.

The bulk superconductors of the Bi-Sr-Ca-Cu-0 system with resistance close to zero at the temperature above llOK have been prepared by solidstate reaction techniques. The onset of. transition is 125K. and the resistance of the bulk samples has a sharp drop ('b98%) near the Tc and i S C l O S e t o zero at 111K. Samples show a good stability. It has been implied that completely cutting off the "resistive tail" of this bulk superconductors should be possible.

B i -S r -C a -C u -0 superconducting fibers have been successfully prepared by m e a n s of the laser-heated pedestal growth m e t h o d . The superconductivity of the fiber sample i s closely related t o the composition of source material, the power of focused laser beams, the p u l i rate of growing fiber, a n d the condition of post-annealing. T h e typical size of samples is 1 5 Q p m ~3 0 m m .T h e o n s e t of transition w a s I I S K , a n d zero resistance was 85K. T h e m a j o r i t y phase an the fibe;s is the 85K (2-2-1-2) phase of the B i -S r -C a -C u -0 materials. S a m p ! e s are sta'bie a n d reproduceable.

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