SUPERCONDUCTING MATERIALS

THE INTERNATIONAL CRYOGENICS MONOGRAPH SERIES

General Editors Dr. K. Mendelssohn, F. R. S. The Clarendon Laboratory Oxford, England

Dr. K. D. Timmerhaus Engineering Research Center University of Colorado, Boulder, Colorado and Engineering Division National Science Foundation, Washington, D.C.

H. 1. Goldsmid Thermoelectric Refrigeration, 1964

G. T. Meaden Electrical Resistance of Metals, 1965

E. S. R. Gopal Specific Heats at Low Temperatures, 1966

M. G. Zabetakis Safety with Cryogenic Fluids, 1967

D. H. Parkinson and B. E. Mulhall The Generation of High Magnetic Fields, 1967

W. E. Keller Helium-3 and Helium-4, 1969

A. 1. Croft Cryogenic Laboratory Equipment, 1970

A. U. Smith Current Trends in Cryobiology, 1970

c.A. Bailey Advanced Cryogenics, 1971

D. A. Wigley Mechanical Properties of Materials at Low Temperatures, 1971

C.M.Hurd The Hall Effect in Metals and A !loys, 1972

E. M. Savitskii, V. V. Baron, Yu. V. Efimov, M. I. Bychkova, and L. F. Myzenkova

Superconducting Materials, 1973

SUPERCONDUCTING MATERIALS

E. M. Savitskii, V. V. Baron, Yu. V. Efimov, M. I. Bychkova, and L. F. Myzenkova

A. A. Baikov Institute of Metallurgy Academy of Sciences of the USSR

Moscow, USSR

Translated from Russian by G. D. Archard

Translation Editor: K. D. Timmerhaus

Engineering Research Center University of Colorado

Boulder, Colorado and

Engineering Division National Science Foundation

Washington, D.C.

PLENUM PRESS • NEW YORK - LONDON

Evgenil Mikhailovich Savitskii was born in 1912 and completed his work at the Institute of Nonferrous Metals and Gold in 1936, specializing in physical metallurgy. From 1937 to 1953 he worked in the Institute of General and Inorganic Chemistry, Academy of Sciences of the USSR, where in 1940 he became the Director of the Mechanical-Testing Laboratory. Since 1953 he has worked in the A. A. Baikov Institute of Metallurgy as the Director of the Laboratory of Rare Metals and Alloys. In 1953 E. M. Savitskii defended his dissertation and obtained the degree of Doctor of Physical Metallurgy. In 1966 he was selected as a Corresponding Member of the Academy of Sciences of the USSR.

Veronika Vladimirovna Baron, Candidate of Technical Sciences, Senior Scientific Fellow, was born in 1914. In 1939 she finished work at the Technological Faculty of the Moscow Institute of Nonferrous Metals and Gold. Since 1944 she has been working in the field of metallurgy in the Institute of General and Inorganic Chemistry, Academy of Sciences of the USSR, and since 1953 in the A. A. Baikov Institute of Metallurgy, Academy of Sciences of the USSR. In 1954 she defended her Candidate's Dissertation.

Yurii Vladimirovich Efimov, Candidate of Technical Sciences, Senior Scientific Fellow, was born in 1931. In 1956 he finished his work at the Physico-Chemical Faculty of the Moscow Institute of Steel and Alloys. Since 1956 he has worked in the A. A. Baikov Institute of Metallurgy, Academy of Sciences of the USSR. In 1967 he defended his Candidate's Dissertation.

Margarita Ivanovna Bychkova, Candidate of Technical Sciences, Junior Scientific Fellow, was born in 1932. In 1956 she finished work at the Moscow Physical-Engineering Institute, specialiZing in physical metallurgy. Since 1957 she has worked in the A. A. Baikov Institute of Metallurgy, Academy of Sciences of the USSR. In 1969 she defended her Candidate's Dissertation.

Larisa Filippovna Myzenkova, Diploma Engineer, Junior Scientific Fellow, was born in 1935. In 1958 she finished work at the Metallurgical Faculty of Leningrad Mining Institute, and since 1959 has worked in the A. A . Baikov Institute of Metallurgy. Academy of Sciences of the USSR.

The original Russian text, published by Nauka Press in Moscow in 1969, has been corrected by the authors for this edition. This translation

is published under an agreement with Mezhdunarodnaya Kniga, the Soviet book export agency.

METALLOVEDENIE SVERKH PROVODY ASHCHIKH MATERIALOV

E. M. Savitskii. V. V. Baron, Yu. V. Efimov, M. I. Bychkova, and L. F. Myzenkova

MeTaJIJIOBe)l.eHHe cBepxnpOBO)l.H~HX MaTepHaJIOB

E. M. C06UI.{KUt/, B. B. DOPOf/., /0. B. E¢UM06, M. 11. DW'lK.06a, Jl. (/>. Mbl3eHKOBa

Library of Congress Catalog Card Number 72-91517

ISBN 978-1-4615-8674-6 ISBN 978-1-4615-8672-2 (eBook) DOl 10.1007/978-1-4615-8672-2

© 1973 Plenum Press, New York Softcover reprint of the hardcover 1st edition 1973 A Division of Plenum Publishing Corporation 227 West 17th Street, New York, N.Y. 10011

United Kingdom edition published by Plenum Press, London A Division of Plenum Publishing Company, Ltd.

Davis House (4th Floor), 8 Scrubs Lane, Harlesden, London NWI0 6SE, England

All rights reserved

No part of this publication may be reproduced in any form without written permission from the publisher

Foreword

With the increased interest in superconductivity applications through­out the world and the necessity of obtaining a firmer understanding of the basic concepts of superconductivity, the editors of the In­ternational Cryogenics Monograph series are extremely grateful for the opportunity to add Superconducting Materials to this series. This comprehensive review and summary of superconducting ma­terials was originally prepared by the Russian authors in 1969 and has been specifically updated for this series. It is the most thorough review of the literature on this subject that has been made to date. Since advances in the development and use of new superconducting materials are largely associated with the general state and level in the development of the physical theory of superconductivity, the physical chemistry of metals, metallography, metal physics, tech­nical physics, and manufacturing techniques, it is hoped that this monograph will provide the stimulus for further advances in all aspects of this exciting field.

The editors express their appreciation to the authors, the translators, and Plenum Publishing Corporation for their assistance and continued interest in making this worthy addition to the series possible.

Washington, D. C. June 1973

v

K. Mendelssohn K. D. Timmerhaus

Foreword to the American Edition

This monograph was published in Russian in 1969 by the Nauka Publishing House on behalf of the Academy of Sciences of the USSR in Moscow. The reasons inspiring the authors to produce this mon­ograph, as well as the leading characteristics of the material pre­sented, are indicate~ in the foreword to the Russian edition. The scientific views expressed in the monograph and the experimental data presented have never encountered any objections in Soviet or other scientific and technical literature.

In preparing the American edition we have introduced cer­tain additions to every section of the monograph. These include the results of various recent publications on the magnetic structure, Debye temperature, and electron specific heat of superconductors, the structure of binary and multi component superconducting alloy systems, together with their composition-T c diagrams, information relating to new superconducting elements, alloys, and compounds, the effect of metallurgical factors and in­terstitial impurities on their properties, new methods of predic­tion, study, and production (composite superconductors), and new fields of application of superconducting materials. In view of the limited amount of additions which may conveniently be made to the text in the course of translation, we have had to give a certain pref­erence to our own experimental material, since the book is of a monograph nature. Among recent investigations carried out in our laboratory in the field of superconducting materials, mention may here be made of our initial attempts at predicting the existence of superconducting compounds and their critical temperatures by computer (using basic data relating to the electron structure of the atoms comprising the compounds), the plotting of the composition-

vii

viii FOREWORD TO THE AklERICAN EDITION

Tc diagrams of ternary and multicomponent systems by experi­ment-planning techniques, the measurement of the critical super­conducting temperature of binary alloys in samples of variable composition, the creation of composite superconductors from two­phase alloys by replacing the low-m.p. phase with another super­conductor, semiconductor, or insulator in the solid -liquid state, and also work on the production of a multiple-filament supercon­ducting cable [1, lal. Research into the construction of phase dia­grams for new superconducting systems and the discovery of ex­perimental laws relating the T c to the composition and constitution of alloys is continuing uninterruptedly. Investigations have started into the effects of extremal conditions (high cooling rates etc.) on the superconducting properties of alloys and compounds and the creation of metastable superconducting phases. Many of the Rus­sian experimental investigations have been published in collections relating to the research and development of super conducting ma­terials produced by the Nauka Publishing House in 1965, 1967, 1969, and 1970 [2-51. The fifth collection (Superconducting Alloys and Compounds) was published in 197L The second collection was translated into English by Consultants Bureau, New York-London (1970) as: Physical Metallurgy of Superconductors, Edited by E. M. Savitskii and V. V. Baron. In relation to individual metals, data regarding superconducting materials have been assembled in a number of monographs written by members of our laboratory [6-111.

In addition to the purely physical theory of the superconduct­ing state of solids, it is essential to emphasize the importance of the physical chemistry of metals and physical metallurgy as a theo­retical basis for the development of new metallic materials pos­sessing special physical properties, including superconductivity. The English reader may acquaint himself with the present state of this problem and with the work which has been carried out in the Soviet Union by considering the monograph of E. M. Savitskii and G. S. Burkhanov: PhYSical Metallurgy of Refractory Metals and Alloys, Plenum Publishing Corporation, New York-London (1970).

As physical chemists, the authors of this monograph adhere to the point of view that all properties of matter and materials de­pend on their internal structure and the technological and service conditions. Many research workers (including ourselves) are daily convinced of the vast amount of information which may be extracted

FOREWORD TO THE AMERICAN EDITION ix

by an intelligent use of the Mendeleev Periodic Table, phase dia­grams, composition-property diagrams, x-ray data, and electron­microscope and metallographic investigations at ordinary and cry­ogenic temperatures in order to secure scientific generalizations and develop new superconducting materials, and also to establish a reasonable technology for the production of these materials, to­gether with a deeper understanding of the complex quantum phe­nomena underlying the superconducting state of matter. The prob­lem of the creation and technological application of superconduct­ing materials is as yet young; it is developing very rapidly, and it may well be that the most important discoveries are still to come. Nevertheless, it is our own opinion that physico-chemical and met­allographic considerations will have as vital a part to play in the future development of this problem as they have hitherto, and that they will contribute fundamentally to its creative merits.

The mutual exchange of information is vital in such a vigor­ously-developing field as the study and application of superconduc­tors. Unfortunately, the language barrier often constitutes one of the major difficulties impeding correlation between the work of scientists in different countries, as well as up-to-date information regarding their research, achievements, and new ideas. Transla­tions of monographs and articles help in reducing this gap. For this reason many important publications by scientists in other countries relating to the problem of superconductivity and super­conducting materials are being translated into Russian in the Soviet Union.

We are grateful to Plenum Publishing Corporation, the Sci­entific Editor, and the translators for their initiative and interest in our monograph and the considerable work involved in its publi­cation in English; we regard this as a friendly act toward our coun­try and ourselves personally.

E. M. Savitskii V. V. Baron Yu. V. Efimov M. 1. Bychkova L. F. Myzenkova

x FOREWORD TO THE AMERICAN EDITION

LITERATURE CITED

1. E. M. Savitskii, Vestnik Akad. Nauk SSSR, 7:44 (1970). 1a. E. M. Savitskii, Izv. Akad. Nauk SSSR, Metally, No.2 (1970).

2. Metallography and Physical Metallurgy of Superconductors, Izd. Nauka, Moscow (1965).

3. Metallography, Physical Chemistry, and Physical Metallurgy of Superconduc­tors, Izd. Nauka, Moscow (1967).

4. Physical Chemistry, Metallography, and Physical Metall urgy of Superconduc­tors, Izd. Nauka, Moscow (1969).

5. Problems of Superconducting Materials, Izd. Nauka, Moscow (1970).

6. E. M. Savitskii and G. S. Burkhanov, Metallography of the Alloys of Refractory and Rare Metals (second revised and supplemented edition), Izd. Nauka (1971).

7. v. F. Terekhova and E. M. Savitskii, Yttrium, Izd. Nauka, Moscow (1967).

8. E. M. Savitskii, M. A. Tylkina, and K. B. Povarova, Rhenium Alloys, Izd. Nauka, Moscow (1965).

9. E. M. Savitskii, V. P. Polyakova, and M. A. Tylkina, Palladium Alloys, Izd. Nauka, Moscow (1967).

10. Yu. V. Efimov, V. V. Baron, and E. M. Savitskii, Vanadium and Its Alloys, Izd. Nauka, Moscow (1969).

11. E. M. Savitskii, V. F. Terekhova, I. V. Burov, I. A. Markova, and O. P. Naum­

kin, Alloys of Rare-Earth Metals, Izd. AN SSSR (1962).

Contents

INTRODUCTION 1

CHAPTER I The Superconducting State of Materials and Methods of Estimating It. . . . . . . . . . . . . . . . . . .. ...... 9

The Phenomenon of Superconductivity . . . . . . . . . . . .. 3 1. History of the Discovery . . . . . . . . . 9 2. Superconductors of the First Group. . 11 3. Superconductors of the Second Group. 12 4. Hard Superconductors. . . . . . . . . . . 13 5. The BCS (Bardeen-Cooper-Schrieffer)

Theory. . . . . . . . . . . . . . . . . . . . . . . . . 14 6. The GLAG (Ginzburg-Landau-Abrikosov-

Gor'kov) Theory . . . . . . . . . . . . . . . . 18 7. The Anderson Model. . . . . . . . . . . . . . . . 22 8 . The Filament (Sponge) Model of a Hard

Superconductor . . . . . . . . . .. 25

Empirical Rules ........................ 27

Methods of Measuring the Critical Superconducting Characteristics of Metals and Alloys. . . . . . . . . . . 37

1. Measuring the Temperature of the Transition into the Superconducting State ........... 37

2. Measurement of Critical Magnetic Fields. 41 3. Measurement of the Critical Current. . . . . . 44

Low-Temperature Technique. 53

xi

xii CONTENTS

Metallography of Superconducting Alloys 59 1. Preparation of Microsections . 59 2. Etching of the Microsections . 62 3. Study of the Microstructure and Properties of

Alloys .••.•.•.••...•.•••.... 0 • 0 •• 66

Literature Cited 73

CHAPTER II Superconducting Elements 81

Properties of Superconducting Elements 81

Effect of Deformation and Interstitial Impurities on the Superconducting Properties of the Elements . . . . . . . . 90

Literature Cited

CHAPTER III Superconducting Compounds.

102

107

Compounds with the Cr3Si Structure. 108

Interstitial Phases and Certain Other Compounds of Metals with Nonmetals . . . . . . . . . . . . . . . . . . 120

Sigma and Laves Phases and Similar Compounds 135

Superconducting Compounds with Other Types of Structures ............................... 150

Effect of Alloying Elements and Impurities on the Structure and Properties of Compounds . . . . . . . 158

1. Effect of Transition Metals on the Properties of Cr3Si-Type Compounds . . . . . . . . . . . .. 159

2. Effect of B Subgroup Elements on the Proper-ties of Cr3Si-Type Compounds . . . . . . . . .. 168

3. Influence of the Simultaneous Replacement of the A and B Components on the Properties of Compounds of the Cr3Si-Type • • • • • • . . • •• 179

a. Effect of Interstitial Impurities on the Proper-ties of Cr3Si Compounds . . . . . . . . . . . . .. 179

5. Effect of Alloying on the Properties of Com-pounds with Other Types of Crystal Structure 184

CONTENTS xiii

Effect of Heat Treatment and Other Factors on the Superconducting Characteristics of Compounds. . . 194

Literature Cited 203

CHAPTER IV Physicochemical Analysis of Superconducting Systems 215

Binary Superconducting Systems. . . . . . . . . . . . 221 1. Systems with Unlimited Solubility in the

Liquid and Solid States . . . . . . . . . . . . 221 2. Systems with Unlimited Solubility and a Poly­

morphic Transformation of the Components .. 228 3. Systems of the Eutectic, Peritectic, and

Monotectic Types. . . . . . . . • . . . • . . . . • •. 252 4. Systems Involving the Formation of Interme-

diate Phases . . . . . . . . . . . . . . . . . . . . . 262

Ternary and More Complex Superconducting Systems. 307 1. Ternary Systems . . . . . . . . . . . . . . . . . . 307 2. Quaternary System. . . . . . • . . • . . . . . . . .. 351 3. Pseudoternary Superconducting Systems. 353 4. Pseudoquaternary System. • . . . . 358

Literature Cited 361

CHAPTER V Production of Superconducting Materials 373

Effect of Composition, Deformation, and Heat Treatment on the Critical Current of Superconducting Alloys . . .. 374

Technology of the Production of Superconducting Alloys 387

Properties and Production Technology of Parts Made from Super conducting Compounds. . . . . . . . . . . . . 391

1. Production of Vanadium-Gallium Wire by Working the Quenched Solid Solution . . . . 392

2. Production of Superconducting Coatings . . 393 3. Production of Super conducting Wire from

Compounds by Working a Mixture of the Orig­inal Components in a Soft Sheath with Subse-quent Heat Treatment (Kunzler Method) . . . .. 401

xiv CONTENTS

4. Production of Superconducting Coatings by Hydrogen Reduction . . . . . . . . . . . . . . . . 407

5. Production of Composite Superconductors from Compounds of the Cr3Si-Type . 0 • • • • 409

6. Production of Large Superconducting Parts. 411

Literature Cited 414

CHAPTER VI Applications . 419

Superconducting Magnets. 420

Computing Technology. . . 430 1. Cryotrons.... 430 2. Memory Devices 431

Electronics and Measuring Technology. 433 1. Bolometers - Receivers of Thermal

Radiation . . . . . . . . . . . . . . . . 433 2. Superconducting Magnetic Lenses. 433 3. Masers....... . . . . . . . . . . . . 434

Nuclear Power and Space . . . . . . . . . . . . . . 436 1. Magnets for Thermonuclear Reactions. 436 2. Elementary-Particle Accelerators 439 3. Bubble Chambers. 440 4. Resonance Pump. . . . 441 5. Gyroscopes...... . . 441 6. "Zero" Magnetic Field 442 7. Magnetohydrodynarriic (MHD) Generators 442 8. Protection of Astronauts from Radiation. 444 9. Hydromagnetic Braking. 445

10. Energy Stores 445

Electrical Machines 445

Conclusion .................... . 447

Literature Cited . • . . . . . . • . . . . . . . • • . . . . . . . . • 451

Ind ex. 0 • • • • • • • • • • 0 • • • • • 0 • • • • • • • 0 • • • • • • .' 457