Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at ...Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at 4.2K,7T(H∥ab)is obtained.The microstructure of the tapes with high J_c values was in- vestigated by transmission electron microscope(TEM)and X-ray energy dispersive spectrum system(EDS). For comparison,a tape fabricated by a different procedure with a low J_c of about 1×10~4 A/cm^2 at 77K,0T was also studied.The relationship between J_c and microstructure of the tapes and the effect of the processing on the microstructure and J_c were elucidated.展开更多
It is well known that for technological application,a great effort has been done to enchance Jvalue ofsuperconducting YBaCuO sintered bulk.Except oxygen content,the main problem for increasing critical cur-rent densit...It is well known that for technological application,a great effort has been done to enchance Jvalue ofsuperconducting YBaCuO sintered bulk.Except oxygen content,the main problem for increasing critical cur-rent density Jis to eliminate the weak link and to control crystallographic anisotropy.It is necessary tomake YBaCuO superconducting bulk have a strong texture with C-axis orientation.Since Jin et al.has suc-展开更多
文摘Ag-sheathed(Bi,Pb)_2Sr_2Ca_2Cu_3O_x tapes were fabricated by a powder-in-tube method.A high critical current density of 2.8×10~4 A/cm^2 at 77K,0T and 4×10~4 A/cm^2 at 4.2K,5T(H⊥ab),6.3× 10~4 A/cm^2 at 4.2K,7T(H∥ab)is obtained.The microstructure of the tapes with high J_c values was in- vestigated by transmission electron microscope(TEM)and X-ray energy dispersive spectrum system(EDS). For comparison,a tape fabricated by a different procedure with a low J_c of about 1×10~4 A/cm^2 at 77K,0T was also studied.The relationship between J_c and microstructure of the tapes and the effect of the processing on the microstructure and J_c were elucidated.
文摘It is well known that for technological application,a great effort has been done to enchance Jvalue ofsuperconducting YBaCuO sintered bulk.Except oxygen content,the main problem for increasing critical cur-rent density Jis to eliminate the weak link and to control crystallographic anisotropy.It is necessary tomake YBaCuO superconducting bulk have a strong texture with C-axis orientation.Since Jin et al.has suc-
