haymeron
Member level 3
residual resistivity ratio ybco
Case Studies in
Superconducting Magnets
Design and Operational Issues
Yukikazu Iwasa
Francis Bitter National Magnet Laboratory
and Department of Mechanical Engineering
Massachusetts Institute of Technology
Cambridge, Massachusetts
Kluwer Academic Publishers
NEW YORK, BOSTON , DORDRECHT, LONDON, MOSCOW
CONTENTS
CHAPTER 1 SUPERCONDUCTING MAGNET TECHNOLOGY 1
1.1 Introductory Remarks 1
1.2 Superconductivity 3
1.3 Magnet-Grade Superconductors 6
1.4 Magnet Design 7
1.5Class 1 and Class 2 Superconducting Magnets 9
1.6 The Format of the Book 9
CHAPTER 2 ELECTROMAGNETIC FIELDS 11
2.1 Introduction 11
2.2 Maxwell’s Equations 11
2.3 Quasi-Static Case 14
2.4 Poynting Vector 15
2.5Field Solutions from the Scalar Potentials 16
Problem 2.1: Magnetized sphere in a uniform field 19
Problem 2.2: Type I superconducting rod in a uniform field 23
Problem 2.3: Magnetic shielding with a spherical shell 26
Problem 2.4: Shielding with a cylindrical shell 32
Problem 2.5: The field far from a cluster of four dipoles 34
Problem 2.6: Induction heating of a cylindrical shell 36
Induction heating—Part 1 (Field) 37
Induction heating—Part 2 (Power Dissipation) 40
Problem 2.7: Eddy-current loss in a metallic strip 43
Lamination to Reduce Eddy-Currrent Loss 44
CHAPTER3 MAGNETS,FIELDS, AND FORCES 45
3.1 Introduction 45
3.2 Law of Biot and Savart 45
3.3 Lorentz Force and Magnetic Pressure 46
Problem 3.1: Uniform-current-density solenoids 48
Bitter Magnet 53
Problem 3.2: Bitter magnet 54
Additional Comments on Water-Cooled Magnets 57
Hybrid Magnet 58
Parameters of Hybrid III Superconducting Magnet (SCM) 59
Problem 3.3: Hybrid Magnet 60
Problem 3.4: Helmholtz coil 62
Problem 3.5: Spatially homogeneous fields 64
Problem 3.6: Notched solenoid 67
ix
x C ONTENTS
Problem 3.7: Ideal dipole magnet 69
Problem 3.8: Ideal quadrupole magnet 74
Problem 3.9: Magnet comprised of two ideal “racetracks” 77
Problem 3.10: Ideal toroidal magnet 84
Nuclear Fusion and Magnetic Confinement 86
Problem 3.11: Fringing field 87
Problem 3.12: Circulating proton in an accelerator 89
Particle Accelerators 89
Problem 3.13: Magnetic force on an iron sphere 91
Problem 3.14: Fault condition in hybrid magnets
1. Fault-mode forces 95
Vertical Magnetic Force during Hybrid III Insert Burnout 97
Problem 3.15: Fault condition in hybrid magnets
2. Mechanical support requirements 98
Problem 3.16: Fault condition in hybrid magnets
3. Fault force transmission 100
Problem 3.17: Stresses in an epoxy-impregnated solenoid 103
Problem 3.18: Stresses in a composite Nb3 Sn conductor 105
CHAPTER4 CRYOGENICS 111
4.1 Introduction 111
4.2 Cryogens 111
4.3 Superfluidity 115
Problem 4.1: Carnot refrigerator 119
Joule-Thomson Process 121
Problem 4.2: Cooling modes of a magnet 122
Problem 4.3: Optimum gas-cooled leads—Part 1 125
Optimum gas-cooled leads—Part 2 130
Problem 4.4: Optimum leads for a vacuum environment—
Normal conductive metal vs HTS 137
Wiedemann-Franz-Lorenz Law and Lorenz Number 139
Problem 4.5: Gas-cooled support rods 140
Structural Materials for Cryogenic Applications 140
Problem 4.6: Subcooled 1.8-K cryostat 142
Problem 4.7: Residual gas heat transfer into a cryostat 148
Heat Input by Residual Gas: “High” Pressure Limit 148
Heat Input by Residual Gas: “Low” Pressure Limit 148
Vacuum Pumping System 149
Vacuum Gauges 150
Problem 4.8: Radiation heat transfer into a cryostat 151
CONTENTS xi
Radiation Heat Transfer: Applications to a Cryostat .........151Effect of Superinsulation Layers ..................151Practical Considerations of Emissivity ...............153Problem 4.9: Laboratory-scale hydrogen (neon) condenser .......155Problem 4.10: Carbon resistor thermometers .............159Effects of a Magnetic Field on Thermometers ............161
CHAPTER 5 MAGNETIZATION OF HARD SUPERCONDUCTORS 1635.1 Introduction ........................163
5.2 Bean’s Critical State Model..................163
5.3 Experimental Confirmation of Bean’s Model ........... 1685.4 A Magnetization Measurement Technique ............ 169
Problem 5.1: Magnetization with transport current
1. Field and then transport current..........172Problem 5.2: Magnetization with transport current
2. Transport current and then field...........176Use of SQUID for Magnetization Measurement ...........176Problem 5.3: Magnetization with transport current
3. Field and then current changes...........179Magnetization Functions – Summary ................ 181Problem 5.4: Critical current density from magnetization ....... 182Contact-Resistance Heating at Test Sample Ends .......... 183Problem 5.5: Magnetization measurement ..............184Problem 5.6: Criterion for flux jumping ..............189Problem 5.7: Flux jumps .....................193Problem 5.8: Filament twisting .................. 195Problem 5.9: Magnetization of conductors .............198Filament Twisting in Composite Superconductors ..........199Problem 5.10: Flux jump criterion for HTS tapes ...........200CHAPTER6 STABILITY 2036.1 Introduction 203
6.2 Stability Theories and Criteria 2036.3 Cable-in-Conduit (CIC) Conductors 206
Problem 6.1: Cryostability
1. Circuit model 210Peak Nucleate Boiling Heat Transfer Flux: Narrow Channels 211Problem 6.2: Cryostability
2. Temperature dependence 212Problem 6.3: Cryostability
3. Stekly criterion 214
xii CONTENTS
Discussion of Stekly Cryostability Criterion .............216
Problem 6.4: Cryostability
4. Nonlinear cooling curves..............217
Composite Superconductors: “Monolithic” and “Built-up” ......217
Problem 6.5: Dynamic stability for tape conductors
1. Magnetic and thermal diffusion...........219
Problem 6.6: Dynamic stability for tape conductors
2. Criterion for edge-cooled tapes........... 222
Problem 6.7: “Equal-area” criterion ................224
Problem 6.8: The MPZ concept ..................227
Problem 6.9: V vs I traces of a cooled composite conductor ......232
Problem 6.10: Stability analyses of Hybrid III SCM .......... 235
Cryostable vs Quasi-Adiabatic (QA) Magnets ............239
Problem 6.11: Stability of CIC conductors ..............240
Problem 6.12: “Ramp-rate-limitation” in CIC conductors .......245
Problem 6.13: MPZ for a composite tape conductor .......... 252
Problem 6.14: Stability of HTS magnets ...............256
CHAPTER 7 AC, SPLICE, AND M ECHANICAL LOSSES 261
7.1 Introduction........................261
7.2 AC Losses.........................262
7.3 Splice Resistance......................266
7.4 Mechanical Disturbances...................268
7.5 Acoustic Emission Technique.................270
Problem 7.1: Hysteresis loss—basic derivation
1. Without transport current.............274
Problem 7.2: Hysteresis loss—basic derivation
2. With transport current.............. 277
Problem 7.3: Hysteresis loss (no transport current)
1. “Small" amplitude cyclic field............280
Problem 7.4: Hysteresis loss (no transport current)
2. “Large” amplitude cyclic field............282
Problem 7.5: Coupling time constant ................284
Problem 7.6: Hysteresis loss of an Nb3Sn strand ...........285
Problem 7.7: AC losses in Hybrid III SCM .............288
“Burst Disk” and Diffuser for Hybrid III Cryostat ..........289
Problem 7.8: AC losses in the US-DPC Coil ............293
Problem 7.9: Splice dissipation in Hybrid III Nb-Ti coil .......300
Mechanical Properties of Tin-Lead Solders .............300
Problem 7.10: A splice for CIC conductors ..............302
Stability of a CIC Splice in a Time-Varying Magnetic Field ......304
CONTENTS xiii
Problem 7.11: Loss due to "index” number 306
Experimental Determination of Index Number 307
Problem 7.12: Frictional sliding 309
Problem 7.13: Source location with AE signals 312
Acoustic Emission Sensor for Cryogenic Environment 314
Problem 7.14: Conductor-motion-induced voltage pulse 315
Problem 7.15: Disturbances in HTS magnets 318
Field Orientation Anisotropy in BiPbSrCaCuO (2223) Tapes 318
CHAPTER8 PROTECTION 323
8.1 Introductory Remarks 323
8.2 Protection for Class 2 Magnets 324
8.3 Computer Simulation 326
Problem 8.1: Active protection 328
Comments on Z Functions for Magnet Protection 332
Problem 8.2: Hot-spot temperatures in Hybrid III SCM 333
Problem 8.3: Quench-voltage detection (QVD)
1. Basic technique using a bridge circuit 336
Problem 8.4: Quench-voltage detection (QVD)
2. An improved technique 338
Voltage Attenuation in Magnet Protection Circuit 339
Problem 8.5: Quench-induced pressure in CIC conductors
1. Analytical approach................ 341
Problem 8.6: Quench-induced pressure in CIC conductors
2. CIC coil for the NHMFL’s 45-T hybrid 345
Problem 8.7: Normal-zone propagation (NZP)
1. Velocity in the longitudinal direction 347
Problem 8.8: Normal-zone propagation (NZP)
2. Transverse (turn-to-turn) velocity 351
Problem 8.9: Passive Protection of "isolated” magnets
1. Basic concepts 355
Problem 8.10: Passive Protection of "isolated” magnets
2. Two-section test coil 358
Problem 8.11: Passive Protection of “isolated” magnets
3. Multi-coil NMR magnet 362
Problem 8.12: NZP velocity in HTS magnets 370
“Dry” High-field HTS magnets operating at 20 K 372
CHAPTER9 CONCLUDINGREMARKS ................375
9.1 Enabling Technology vs Replacing Technology 375
9.2 Outlook for the HTS 376
xiv CONTENTS
APPENDIX IPHYSICAL CONSTANTS AND CONVERSION FACTORS 377
Table A1.1 Selected Physical Constants .............. 377
Table A1.2 Selected Conversion Factors ..............378
APPENDIX II THERMODYNAMIC PROPERTIES OF CRYOGENS 379
Table A2.1 Helium at 1 Atm 379
Table A2.2 Helium at Saturation 380
Figure A2.1 Isochoric P(T) curves for helium at two densities 381
Figure A2.2 Isochoric u(T) curves for helium at two densities 382
Table A2.3 Selected Properties of Cryogens at 1 Atm 383
Table A2.4 Heat Transfer Properties of Cryogen Gases at 1 Atm. . .383
APPENDIX III PHYSICAL PROPERTIES OF M ATERIALS 385
Figure A3.1 Thermal conductivity vs temperature plots. ....... 385
Figure A3.2 Heat capacity vs temperature plots. ........ 386
Figure A3.3 Volumetric enthalpy vs temperature plots. ........387
Table A3.1 Mechanical Properties of Materials ........... 388
Table A3.2 Mean Linear Thermal Expansion of Materials ......389
APPENDIX IV ELECTRICAL PROPERTIES OF NORMAL METALS 391
Figure A4.1 Normalized zero-field electrical resistivity vs
temperature plots 391
Figure A4.2 Kohler plotsFigure A4.3 Copper Residual Resistivity Ratio (RRR) vs
392
magnetic induction plots 393
Table A4.1 Electrical Resistivity of Heater Metals 394
APPENDIX V PROPERTIES OF SUPERCONDUCTORS 395
Table A5.1 Bc 2 vs T Data for Nb-Ti 395
Table A5.2 Bc 2 vs T Data for Nb3 Sn. 395
Figure A5.1 J c vs B plots for Nb-Ti at 1.8 and 4.2K 396
Figure A5.2 J c vs B plots for Nb3 Sn at 1.8, 4.2, 10, and 12K. 397
Table A5.3 Parameters of BiPbSrCaCuO (2223) 398
Figure A5.3 J c vs B plots for BiPbSrCaCuO (2223) at 4.2 and 27K. . 398
Table A5.4 Selected Physical Properties of YBCO and BSCCO 399
APPENDIXVI GLOSSARY 401
APPENDIX VII QUOTATION SOURCES AND CHARACTER IDENTIFICATION 413
INDEX 415
Case Studies in
Superconducting Magnets
Design and Operational Issues
Yukikazu Iwasa
Francis Bitter National Magnet Laboratory
and Department of Mechanical Engineering
Massachusetts Institute of Technology
Cambridge, Massachusetts
Kluwer Academic Publishers
NEW YORK, BOSTON , DORDRECHT, LONDON, MOSCOW
CONTENTS
CHAPTER 1 SUPERCONDUCTING MAGNET TECHNOLOGY 1
1.1 Introductory Remarks 1
1.2 Superconductivity 3
1.3 Magnet-Grade Superconductors 6
1.4 Magnet Design 7
1.5Class 1 and Class 2 Superconducting Magnets 9
1.6 The Format of the Book 9
CHAPTER 2 ELECTROMAGNETIC FIELDS 11
2.1 Introduction 11
2.2 Maxwell’s Equations 11
2.3 Quasi-Static Case 14
2.4 Poynting Vector 15
2.5Field Solutions from the Scalar Potentials 16
Problem 2.1: Magnetized sphere in a uniform field 19
Problem 2.2: Type I superconducting rod in a uniform field 23
Problem 2.3: Magnetic shielding with a spherical shell 26
Problem 2.4: Shielding with a cylindrical shell 32
Problem 2.5: The field far from a cluster of four dipoles 34
Problem 2.6: Induction heating of a cylindrical shell 36
Induction heating—Part 1 (Field) 37
Induction heating—Part 2 (Power Dissipation) 40
Problem 2.7: Eddy-current loss in a metallic strip 43
Lamination to Reduce Eddy-Currrent Loss 44
CHAPTER3 MAGNETS,FIELDS, AND FORCES 45
3.1 Introduction 45
3.2 Law of Biot and Savart 45
3.3 Lorentz Force and Magnetic Pressure 46
Problem 3.1: Uniform-current-density solenoids 48
Bitter Magnet 53
Problem 3.2: Bitter magnet 54
Additional Comments on Water-Cooled Magnets 57
Hybrid Magnet 58
Parameters of Hybrid III Superconducting Magnet (SCM) 59
Problem 3.3: Hybrid Magnet 60
Problem 3.4: Helmholtz coil 62
Problem 3.5: Spatially homogeneous fields 64
Problem 3.6: Notched solenoid 67
ix
x C ONTENTS
Problem 3.7: Ideal dipole magnet 69
Problem 3.8: Ideal quadrupole magnet 74
Problem 3.9: Magnet comprised of two ideal “racetracks” 77
Problem 3.10: Ideal toroidal magnet 84
Nuclear Fusion and Magnetic Confinement 86
Problem 3.11: Fringing field 87
Problem 3.12: Circulating proton in an accelerator 89
Particle Accelerators 89
Problem 3.13: Magnetic force on an iron sphere 91
Problem 3.14: Fault condition in hybrid magnets
1. Fault-mode forces 95
Vertical Magnetic Force during Hybrid III Insert Burnout 97
Problem 3.15: Fault condition in hybrid magnets
2. Mechanical support requirements 98
Problem 3.16: Fault condition in hybrid magnets
3. Fault force transmission 100
Problem 3.17: Stresses in an epoxy-impregnated solenoid 103
Problem 3.18: Stresses in a composite Nb3 Sn conductor 105
CHAPTER4 CRYOGENICS 111
4.1 Introduction 111
4.2 Cryogens 111
4.3 Superfluidity 115
Problem 4.1: Carnot refrigerator 119
Joule-Thomson Process 121
Problem 4.2: Cooling modes of a magnet 122
Problem 4.3: Optimum gas-cooled leads—Part 1 125
Optimum gas-cooled leads—Part 2 130
Problem 4.4: Optimum leads for a vacuum environment—
Normal conductive metal vs HTS 137
Wiedemann-Franz-Lorenz Law and Lorenz Number 139
Problem 4.5: Gas-cooled support rods 140
Structural Materials for Cryogenic Applications 140
Problem 4.6: Subcooled 1.8-K cryostat 142
Problem 4.7: Residual gas heat transfer into a cryostat 148
Heat Input by Residual Gas: “High” Pressure Limit 148
Heat Input by Residual Gas: “Low” Pressure Limit 148
Vacuum Pumping System 149
Vacuum Gauges 150
Problem 4.8: Radiation heat transfer into a cryostat 151
CONTENTS xi
Radiation Heat Transfer: Applications to a Cryostat .........151Effect of Superinsulation Layers ..................151Practical Considerations of Emissivity ...............153Problem 4.9: Laboratory-scale hydrogen (neon) condenser .......155Problem 4.10: Carbon resistor thermometers .............159Effects of a Magnetic Field on Thermometers ............161
CHAPTER 5 MAGNETIZATION OF HARD SUPERCONDUCTORS 1635.1 Introduction ........................163
5.2 Bean’s Critical State Model..................163
5.3 Experimental Confirmation of Bean’s Model ........... 1685.4 A Magnetization Measurement Technique ............ 169
Problem 5.1: Magnetization with transport current
1. Field and then transport current..........172Problem 5.2: Magnetization with transport current
2. Transport current and then field...........176Use of SQUID for Magnetization Measurement ...........176Problem 5.3: Magnetization with transport current
3. Field and then current changes...........179Magnetization Functions – Summary ................ 181Problem 5.4: Critical current density from magnetization ....... 182Contact-Resistance Heating at Test Sample Ends .......... 183Problem 5.5: Magnetization measurement ..............184Problem 5.6: Criterion for flux jumping ..............189Problem 5.7: Flux jumps .....................193Problem 5.8: Filament twisting .................. 195Problem 5.9: Magnetization of conductors .............198Filament Twisting in Composite Superconductors ..........199Problem 5.10: Flux jump criterion for HTS tapes ...........200CHAPTER6 STABILITY 2036.1 Introduction 203
6.2 Stability Theories and Criteria 2036.3 Cable-in-Conduit (CIC) Conductors 206
Problem 6.1: Cryostability
1. Circuit model 210Peak Nucleate Boiling Heat Transfer Flux: Narrow Channels 211Problem 6.2: Cryostability
2. Temperature dependence 212Problem 6.3: Cryostability
3. Stekly criterion 214
xii CONTENTS
Discussion of Stekly Cryostability Criterion .............216
Problem 6.4: Cryostability
4. Nonlinear cooling curves..............217
Composite Superconductors: “Monolithic” and “Built-up” ......217
Problem 6.5: Dynamic stability for tape conductors
1. Magnetic and thermal diffusion...........219
Problem 6.6: Dynamic stability for tape conductors
2. Criterion for edge-cooled tapes........... 222
Problem 6.7: “Equal-area” criterion ................224
Problem 6.8: The MPZ concept ..................227
Problem 6.9: V vs I traces of a cooled composite conductor ......232
Problem 6.10: Stability analyses of Hybrid III SCM .......... 235
Cryostable vs Quasi-Adiabatic (QA) Magnets ............239
Problem 6.11: Stability of CIC conductors ..............240
Problem 6.12: “Ramp-rate-limitation” in CIC conductors .......245
Problem 6.13: MPZ for a composite tape conductor .......... 252
Problem 6.14: Stability of HTS magnets ...............256
CHAPTER 7 AC, SPLICE, AND M ECHANICAL LOSSES 261
7.1 Introduction........................261
7.2 AC Losses.........................262
7.3 Splice Resistance......................266
7.4 Mechanical Disturbances...................268
7.5 Acoustic Emission Technique.................270
Problem 7.1: Hysteresis loss—basic derivation
1. Without transport current.............274
Problem 7.2: Hysteresis loss—basic derivation
2. With transport current.............. 277
Problem 7.3: Hysteresis loss (no transport current)
1. “Small" amplitude cyclic field............280
Problem 7.4: Hysteresis loss (no transport current)
2. “Large” amplitude cyclic field............282
Problem 7.5: Coupling time constant ................284
Problem 7.6: Hysteresis loss of an Nb3Sn strand ...........285
Problem 7.7: AC losses in Hybrid III SCM .............288
“Burst Disk” and Diffuser for Hybrid III Cryostat ..........289
Problem 7.8: AC losses in the US-DPC Coil ............293
Problem 7.9: Splice dissipation in Hybrid III Nb-Ti coil .......300
Mechanical Properties of Tin-Lead Solders .............300
Problem 7.10: A splice for CIC conductors ..............302
Stability of a CIC Splice in a Time-Varying Magnetic Field ......304
CONTENTS xiii
Problem 7.11: Loss due to "index” number 306
Experimental Determination of Index Number 307
Problem 7.12: Frictional sliding 309
Problem 7.13: Source location with AE signals 312
Acoustic Emission Sensor for Cryogenic Environment 314
Problem 7.14: Conductor-motion-induced voltage pulse 315
Problem 7.15: Disturbances in HTS magnets 318
Field Orientation Anisotropy in BiPbSrCaCuO (2223) Tapes 318
CHAPTER8 PROTECTION 323
8.1 Introductory Remarks 323
8.2 Protection for Class 2 Magnets 324
8.3 Computer Simulation 326
Problem 8.1: Active protection 328
Comments on Z Functions for Magnet Protection 332
Problem 8.2: Hot-spot temperatures in Hybrid III SCM 333
Problem 8.3: Quench-voltage detection (QVD)
1. Basic technique using a bridge circuit 336
Problem 8.4: Quench-voltage detection (QVD)
2. An improved technique 338
Voltage Attenuation in Magnet Protection Circuit 339
Problem 8.5: Quench-induced pressure in CIC conductors
1. Analytical approach................ 341
Problem 8.6: Quench-induced pressure in CIC conductors
2. CIC coil for the NHMFL’s 45-T hybrid 345
Problem 8.7: Normal-zone propagation (NZP)
1. Velocity in the longitudinal direction 347
Problem 8.8: Normal-zone propagation (NZP)
2. Transverse (turn-to-turn) velocity 351
Problem 8.9: Passive Protection of "isolated” magnets
1. Basic concepts 355
Problem 8.10: Passive Protection of "isolated” magnets
2. Two-section test coil 358
Problem 8.11: Passive Protection of “isolated” magnets
3. Multi-coil NMR magnet 362
Problem 8.12: NZP velocity in HTS magnets 370
“Dry” High-field HTS magnets operating at 20 K 372
CHAPTER9 CONCLUDINGREMARKS ................375
9.1 Enabling Technology vs Replacing Technology 375
9.2 Outlook for the HTS 376
xiv CONTENTS
APPENDIX IPHYSICAL CONSTANTS AND CONVERSION FACTORS 377
Table A1.1 Selected Physical Constants .............. 377
Table A1.2 Selected Conversion Factors ..............378
APPENDIX II THERMODYNAMIC PROPERTIES OF CRYOGENS 379
Table A2.1 Helium at 1 Atm 379
Table A2.2 Helium at Saturation 380
Figure A2.1 Isochoric P(T) curves for helium at two densities 381
Figure A2.2 Isochoric u(T) curves for helium at two densities 382
Table A2.3 Selected Properties of Cryogens at 1 Atm 383
Table A2.4 Heat Transfer Properties of Cryogen Gases at 1 Atm. . .383
APPENDIX III PHYSICAL PROPERTIES OF M ATERIALS 385
Figure A3.1 Thermal conductivity vs temperature plots. ....... 385
Figure A3.2 Heat capacity vs temperature plots. ........ 386
Figure A3.3 Volumetric enthalpy vs temperature plots. ........387
Table A3.1 Mechanical Properties of Materials ........... 388
Table A3.2 Mean Linear Thermal Expansion of Materials ......389
APPENDIX IV ELECTRICAL PROPERTIES OF NORMAL METALS 391
Figure A4.1 Normalized zero-field electrical resistivity vs
temperature plots 391
Figure A4.2 Kohler plotsFigure A4.3 Copper Residual Resistivity Ratio (RRR) vs
392
magnetic induction plots 393
Table A4.1 Electrical Resistivity of Heater Metals 394
APPENDIX V PROPERTIES OF SUPERCONDUCTORS 395
Table A5.1 Bc 2 vs T Data for Nb-Ti 395
Table A5.2 Bc 2 vs T Data for Nb3 Sn. 395
Figure A5.1 J c vs B plots for Nb-Ti at 1.8 and 4.2K 396
Figure A5.2 J c vs B plots for Nb3 Sn at 1.8, 4.2, 10, and 12K. 397
Table A5.3 Parameters of BiPbSrCaCuO (2223) 398
Figure A5.3 J c vs B plots for BiPbSrCaCuO (2223) at 4.2 and 27K. . 398
Table A5.4 Selected Physical Properties of YBCO and BSCCO 399
APPENDIXVI GLOSSARY 401
APPENDIX VII QUOTATION SOURCES AND CHARACTER IDENTIFICATION 413
INDEX 415
