DC-transport properties of QMG current limiting elements

V-I properties of YBCO bulk superconductor (QMG: YBa/sub 2/Cu/sub 3/O/sub x/ bulk single crystal containing Y/sub 2/BaCuO/sub x/ particles) were measured using pulse current at 77 K and 87 K to obtain basic data for super-normal transition. Because of its high Jc property QMG is a promising bulk material for HTC-FCL application. I-shaped QMG rods having cross section of 0.5 mm/spl times/1.0 mm were prepared to measure voltage due to pulse current. The plots of InV vs. InI yielded a straight line with a slope ranging from 5.8 to 7.9 at 77 K. By changing the amplitude and duration of pulses the time from the start of feeding current till the occurrence of quench were obtained for various amplitudes of pulse current. In this experiment, it is considered that the quench did not occur in the whole rod but only in a small part.