Pulling rate and current intensity competition in an electrically assisted laser floating zone

摘要

Bi-Sr-Ca-Cu-O (BSCCO) superconducting fibres were grown using the laser floating zone technique assisted by a dc electrical current (electrically assisted laser floating zone—EALFZ process). The simultaneous effect of pulling rate and applied current intensity was evaluated on the premises of the: (i) elemental partition coefficient between solid and molten zone; (ii) phase development; (iii) crystal size and alignment degree of the primary and superconducting phases; (iv) phase transformation during heat treatment and (v) superconducting properties. The highest critical current density value (Jc = 2240 A cm-2) was obtained for the fibres pulled at intermediate pulling rates (75 mm h~(-1)) grown under a maximum dc electric current intensity (200 mA).