Title :
Process parameter dependent characteristics of centrifugally formed HTS Bi-2212 tubes
Author :
Park, C.W. ; Lee, N.I. ; Jang, G.E. ; Ha, D.W. ; Sung, T.H.
Author_Institution :
Dept. of Mater. Eng., Chungbuk Nat. Univ., South Korea
fDate :
6/1/2005 12:00:00 AM
Abstract :
HTS Bi-2212 tubes were fabricated in terms of many different processing parameters by Centrifugal Forming Method. Initially powder was melted by induction heating. The optimum range of melting temperatures and mold preheating temperature were 1050°C∼1100°C and 500°C for 30 min respectively. The nominal mold rotating speed was 1,000 rpm. A tube was annealed at 840°C for 80 Hrs in oxygen atmosphere. The plates like grains more than 40 μm were well developed along the rotating direction of mold. It was found that the tube processed with higher mold preheating temperature and faster rate of mold rotation speed shows better electric characteristics as compared with the tube normally processed. Uniform tube fabrication is one of the critical issues to satisfy the simultaneous quenching for the successful application in the resistive SCFCL.
Keywords :
bismuth compounds; calcium compounds; high-temperature superconductors; induction heating; melt spinning; powder technology; quenching (thermal); rapid thermal annealing; strontium compounds; 1050 to 1100 C; 30 min; 40 micron; 500 C; 80 hr; 840 C; Bi2Sr2CaCu2O8; HTS Bi-2212 tubes; annealing; centrifugal forming method; high temperature superconductors; induction heating; melting temperature; mold preheating temperature; mold rotating speed; powder; processing parameters; quenching; resistive SCFCL; superconducting fault current limiters; tube fabrication; Casting; Critical current density; Electric variables; Fault currents; High temperature superconductors; Impedance; Superconducting materials; Superconductivity; Switches; Temperature distribution; Centrifugal forming method; mold preheating temperature; mold rotating speed; uniformity;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2005.848746