TY - GEN
T1 - Influence of oxygen partial pressure on the microstructures and critical current densities of PMP-processed YBCO bulks with submicron y 2BaCuO5 particles
AU - Chen, S. K.
AU - Zhou, L.
AU - Wang, K. G.
AU - Zhang, P. X.
AU - Feng, Y.
AU - Wen, H. H.
AU - Li, S. L.
PY - 2007
Y1 - 2007
N2 - YBCO bulks with submicron Y2BaCuO5 particles have been prepared under oxygen partial pressures of 0.21atm and latm, respectively, by the powder melting process (PMP). The microstructures, oxygen contents and critical current densities of the samples have been investigated. The results showed that the sample grown under P(O2) = 1 atm contained Y 2BaCuO5 particles with a little bigger average size and had a slightly higher density of stacking faults than the one prepared under P(O2) = 0.21 atm. Oxygen content measurements indicated that the as-grown sample under P(O2) = 1 atm had a higher oxygen content. After post-annealing in flowing oxygen, the oxygen content of the P(O 2) = 1 atm sample was still higher than that of the P(O2) = 0.21 atm sample. They were examined to be 6.94 and 6.88 with X-ray diffraction for the two oxygenated samples, respectively. Magnetization measurements have been performed on the two types of oxygenated samples and critical current densities (Jc) have been calculated based on the extended Bean critical state model. The P(O2) = 0.21 atm sample exhibits J c values of 5.47×105 A/cm2 and 2.22×104 A/cm2 in 1 T magnetic field at 20K and 77K, respectively. The P(O2) = 1 atm sample, meanwhile, has Jc values of 9.46×105 A/cm2 and 1.47×10 4 A/cm2 in 1 T magnetic field at 20K and 77K, respectively. Moreover, at 20K, the Jc of the P(O2) = 1 atm sample is higher than that of the P(O2) = 0.21 atm sample in an applied magnetic field up to 5 T. At 77K, however, the Jc of the P(O2) = 1 atm sample drops more quickly than that of the P(O 2) = 0.21 atm sample. The mechanisms of the different microstructures, oxygen contents and magnetic field dependence behaviors of Jc for the two kinds of samples have been discussed.
AB - YBCO bulks with submicron Y2BaCuO5 particles have been prepared under oxygen partial pressures of 0.21atm and latm, respectively, by the powder melting process (PMP). The microstructures, oxygen contents and critical current densities of the samples have been investigated. The results showed that the sample grown under P(O2) = 1 atm contained Y 2BaCuO5 particles with a little bigger average size and had a slightly higher density of stacking faults than the one prepared under P(O2) = 0.21 atm. Oxygen content measurements indicated that the as-grown sample under P(O2) = 1 atm had a higher oxygen content. After post-annealing in flowing oxygen, the oxygen content of the P(O 2) = 1 atm sample was still higher than that of the P(O2) = 0.21 atm sample. They were examined to be 6.94 and 6.88 with X-ray diffraction for the two oxygenated samples, respectively. Magnetization measurements have been performed on the two types of oxygenated samples and critical current densities (Jc) have been calculated based on the extended Bean critical state model. The P(O2) = 0.21 atm sample exhibits J c values of 5.47×105 A/cm2 and 2.22×104 A/cm2 in 1 T magnetic field at 20K and 77K, respectively. The P(O2) = 1 atm sample, meanwhile, has Jc values of 9.46×105 A/cm2 and 1.47×10 4 A/cm2 in 1 T magnetic field at 20K and 77K, respectively. Moreover, at 20K, the Jc of the P(O2) = 1 atm sample is higher than that of the P(O2) = 0.21 atm sample in an applied magnetic field up to 5 T. At 77K, however, the Jc of the P(O2) = 1 atm sample drops more quickly than that of the P(O 2) = 0.21 atm sample. The mechanisms of the different microstructures, oxygen contents and magnetic field dependence behaviors of Jc for the two kinds of samples have been discussed.
KW - Bulk
KW - Oxygen partial pressure
KW - PMP
KW - Submicron YBaCuO
KW - YBCO
UR - http://www.scopus.com/inward/record.url?scp=38549121232&partnerID=8YFLogxK
U2 - 10.4028/0-87849-432-4.1887
DO - 10.4028/0-87849-432-4.1887
M3 - 会议稿件
AN - SCOPUS:38549121232
SN - 0878494324
SN - 9780878494323
T3 - Materials Science Forum
SP - 1887
EP - 1892
BT - Progress in Light Metals, Aerospace Materials and Superconductors
PB - Trans Tech Publications Ltd
T2 - 2006 Beijing International Materials Week, 2006 BIMW - International Conference on Superconducting Materials, ICSM 2006
Y2 - 25 June 2006 through 30 June 2006
ER -