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Joseph Minervini. MacDonald, Timothy A. (Timothy Alan), 1974- Massachusetts Institute of Technology. Dept. of Nuclear Engineering. Massachusetts Institute of Technology. Department of Nuclear Engineering Massachusetts Institute of Technology. Department of Nuclear Science and Engineering 2010-12-06T17:27:46Z 2010-12-06T17:27:46Z 2000 2000 http://hdl.handle.net/1721.1/60136 48546468 Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 2000. Includes bibliographical references (p. 151-153). The critical currents of silver sheathed multifilamentary Bi 2Sr 2Ca2 Cu3010 (BSCCO- 2223/Ag) tapes at temperatures ranging from 77 K to 110 K were measured using a typical four-terminal technique for two different BSCCO-2223/Ag tapes manufactured by Vacuumschmelze (VAC). The critical currents for the two VAC samples were measured as a function of magnetic field strength. The critical current of each sample was well described by the generalized Kim model. The critical current was also measured as a function of angle of the magnetic field with respect to the plane of the tapes, in all cases perpendicular to the transport current flow. Both samples displayed a high sensitivity to the magnetic field orientation with the largest critical currents measured when the magnetic field was in-plane with the broad face of the tapes. The current ramp rate effect on the critical current was investigated and showed no significant effect on the critical current measurements for ramp speeds between 6 A/min and 120 A/min. The energy dissipation or AC losses as a function of peak AC magnetic field, magnetic field sweep frequency, and transport current for a VAC sample and a sample manufactured by IGC - Advanced Superconductors (IGC) were measured at 77 K. The losses were measured using a pick up coil with a lock-in amplifier to measure the magnetization of the superconducting samples. The AC losses of both samples displayed complete electromagnetic coupling of the superconducting filaments at magnetic sweep frequencies of approximately 0.1 Hz. These results are consistent with results measured at magnetic field sweep frequencies of 60 Hz. by Timothy A. MacDonald. S.M. 164 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Nuclear Engineering. Electrical characterization of high temperature superconductors as a function of temperature Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="ff4f24cb-4879-4095-9373-e6625ce10da9"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Electrical characterization of high temperature superconductors as a function of temperature</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2000</PublicationDate> <Authors> <Author> <DisplayName>MacDonald, Timothy A. (Timothy Alan), 1974-</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Nuclear Engineering.</Keyword> <Abstract>The critical currents of silver sheathed multifilamentary Bi 2Sr 2Ca2 Cu3010 (BSCCO- 2223/Ag) tapes at temperatures ranging from 77 K to 110 K were measured using a typical four-terminal technique for two different BSCCO-2223/Ag tapes manufactured by Vacuumschmelze (VAC). The critical currents for the two VAC samples were measured as a function of magnetic field strength. The critical current of each sample was well described by the generalized Kim model. The critical current was also measured as a function of angle of the magnetic field with respect to the plane of the tapes, in all cases perpendicular to the transport current flow. Both samples displayed a high sensitivity to the magnetic field orientation with the largest critical currents measured when the magnetic field was in-plane with the broad face of the tapes. The current ramp rate effect on the critical current was investigated and showed no significant effect on the critical current measurements for ramp speeds between 6 A/min and 120 A/min. The energy dissipation or AC losses as a function of peak AC magnetic field, magnetic field sweep frequency, and transport current for a VAC sample and a sample manufactured by IGC - Advanced Superconductors (IGC) were measured at 77 K. The losses were measured using a pick up coil with a lock-in amplifier to measure the magnetization of the superconducting samples. The AC losses of both samples displayed complete electromagnetic coupling of the superconducting filaments at magnetic sweep frequencies of approximately 0.1 Hz. These results are consistent with results measured at magnetic field sweep frequencies of 60 Hz.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>