© Korean Powder Metallurgy Institute 1238
-PC14-W-01
2006 POWDER METALLURGY World Congress
PC14-W-02
Particle Distribution in Melt-textured Y-Ba-Cu-O Superconductors
Byung-Hyuk Jun1, Asif Mahmood1, Soon-Dong Park1, Chan Joong Kim1 1
Superconductivity Lab., Korea Atomic Energy Research Institute, Korea
The particle distribution in large grain Y-Ba-Cu-O (YBCO) superconductors were investigated. It was found that the Y2BaCuO5 (211) second particles were often trapped in YBCO growing from a liquid. The 211 particles made a special track pattern which met at the corners of the grown YBCO grains. The formation of the 211 tracks was found to be dependant on the growth velocity of YBCO grain, particle size and density of 211. We explain the particle trapping nature in YBCO-211-melt ternary system in terms of interfacial energy relationship among the three phases.
Melt and Caseted Bisrcacuo Tubes for Fault Current Limiters
Chan Joong Kim1, Jung-Suk Choi1, Byung-Hyuk Jun1, Ki-Ik Kim1, Ok-Bae Hyun2 1
Superconductivity Lab., Korea Atomic Energy Research Institute, Korea,
2
Korea Electric Power Research Institute, Korea Electric Power Research Institute, Korea
The Bi2Sr2Ca1Cu2Ox (BSCCO) superconducting tubes for fault current limiter were fabricated by power mixing, melt and casting. 10 wt.% of SrSO4 was mixed with BSCCO powder to enhance the melt viscosity and mechanical properties. The melt casted BSCCO tubes were annealed at 800 C-840 C and at oxygen atmosphere to form a superconducting phase and subsequently annealed again at reduced atmosphere to control the oxygen content in the superconducting phase. The phases formed in BSCCO tubes were analyzed by XRD and SEM microscopy. It was found that the plate-like superconducting phase was developed by the high temperature annealing and the size of the plate was dependant on the annealing temperature. The current properties of the BSCCO tubes were measured by I-V measurement. The current density over 500 Amp. and 1000 Amp. was achieved at 77 K and 65 K, respectively. We will report the details of the fabrication process of the melt and cast process to achieve high current properties.
