Handbook of Magnetic Phenomena

439 Pages·1986·10.859 MB·English

by  Harry E. Burke (auth.)

HANDBOOK
of
MAGNETIC PHENOMENA
HANDBOOK
of
MAGNETIC PHENOMENA
Harry E. Burke
~ VAN NOSTRAND REINHOLD COMPANY
_________N ewYork
~
Copyright C[) 1986 by Van Nostrand Reinhold Company Inc.
Softcover reprint of the hardcover 1st edition 1986
Library of Congress Catalog Card Number: 85-2409
ISBN-13: 978-94-011-7008-6
All rights reserved. No part of this work covered by the copyright hereon may
be reproduccd or used in any form or by any means-graphic, electronic, or
mechanical, including photocopying, recording, taping, or information storage
and retrieval systems-without written permission of the publisher.
Published by Van Nostrand Reinhold Company Inc.
115 Fifth Avenue
New York, New York 10003
Van Nostrand Reinhold Company Limited
Molly MiHars Lane
Wokingham, Berkshire RG II 2PY, England
Van Nostrand Reinhold
480 La Trobe Street
Melbourne, Victoria 3000, Australia
Macmillan of Canada
Division of Canada Publishing Corporation
164 Commander Boulevard
Agincourt, Ontario MIS 3C7, Canada
15 14 13 12 II 1098765432
Library of Congress Cataloging in Publication Data
Burke, Harry E.
Handbook of magnetic phenomcna.
Includes index.
\. Magnetism. 2. Electronics. I. Title.
QC7532.B85 1985 538 85-2409
ISBN -13: 978-94-011-7008-6 e-ISBN -13: 978-94-011-7006-2
DOT: 10.1007/978-94-011-7006-2
Dedicated to
Jeffrey Michael Burke
and to his great great grandfather,
Herman Daniel Burke (1842-1888)
who was wounded both at Gettysburg and in the Wilderness and later by Indians on
his way to California
and to his great great great grandfather,
William Cleminson Armstrong (1815-1874)
who, as a civilian, was dragged from a sick bed to spend the Civil War
in a Union prison.
PREFACE
The general theory of magnetism and the vast range of individual phe
nomena it embraces have already been examined in many volumes. Spe
cialists hardly need help in charting their way through the maze of pub
lished information. At the same time, a nonspecialist might easily be
discouraged by this abundance. Most texts are restricted in their coverage,
and their concepts may well appear to be disorganized when the uninitiated
attempt to consider them in their totality. Since the subject is already
thoroughly researched with very little new information added year by year,
this is hardly a satisfactory state of affairs. By now, it should be possible
for anyone with even a minimum of technical competence to feel com
pletely at home with all of the basic magnetic principles.
The present volume addresses this issue by stressing simplicity-sim
plicity of order and simplicity of range as well as simplicity of detail. It
proposes a pattern of logical classification based on the electronic con
sequences that result whenever any form of matter interacts with any kind
of energy. An attempt has been made to present each phenomenon of
interest in its most visually graphic form while reducing the verbal de
scription to the minimum needed to back up the illustrations. This might
be called a Life magazine type of approach, in which each point is prin
cipally supported by a picture. The illustrations make use of two (perhaps
unique) conventions. First, small dots are used to indicate slow-moving
(cold) electronic carriers, whereas large dots stand for fast-moving (hot)
ones. This difference in size helps dramatize the relationship between
thermal and electronic phenomena. Second, the small spinning charged
particles that represent magnetized bodies-microminiature magnets-are
referred to as "magnetons." (All sub molecular particles spin, whether
charged or uncharged.) The various ways magnetons relate to each other
in terms of both their electric charge and their magnetic polarization con
stitute the bases for many magnetic phenomena.
Having recognized first that all magnetic phenomena are ultimately based
on Ampere's Law, which relates a magnetic field to a moving electric
charge, the discussion proceeds to the Biot-Savart fields that surround
vii
viii PREFACE
the linear paths of all electric currents and then to the toroidal fields that
surround both current-carrying coils and spinning electric charges. Cur
rent-carrying coils are used to construct electromagnets, whereas spinning
charged bodies are responsible for permanent magnetic phenomena.
All told, there are more than four times as many different magnetic
phenomena detailed here than can be found in any other publication known
to the author.
This book is divided into five parts. Part I explores the relationships
between moving electrically charged particles and the various energy
components of the environments through which they move. Part II in
vestigates the effects of magnetic field changes on these particles. The
next three parts discuss what happens magnetically to moving magnetons.
Part III discusses the consequences that may be expected when magnetons
move under tight constraints, as in a solid or liquid. Part IV discusses the
consequences when they are able to move without much interference from,
or interaction with, other particles in the same environment, as in a vacuum
or gas. In conclusion, Part V considers the quite different consequences
when magnetons are able to move through crystalline structures without
significant energy interchange.
HARRY E. BURKE
CONTENTS
Preface vii
I. Introduction .......................................................... 1
1.1 Magnetotransduction .......................................... I
1.2 Discussion Boundaries ........................................ 2
1.3 Model .......................................................... 3
1.4 Audience ....................................................... 5
1.5 Theme .......................................................... 6
Part 1: Environments Experienced by Moving Electric Charges 7
2. Basic Laws and Definitions ......................................... 9
2.1 The Three Types of Field .................................... 9
2.2 Definition of a Magnetic Field .............................. 10
2.3 Electrically Charged Particles ............................... 10
2.4 Moving Electrically Charged Particles...................... II
2.5 Flux Lines .................................................... 12
2.6 Magnetic Poles ............................................... 13
2.7 Forces on Moving Electrically Charged Particles ......... 15
2.8 Paths Followed by Moving Charged Particles ............. 16
2.9 Toroidal Magnetic Fields .................................... 18
2.10 Magnetic Field Direction ................................... 19
2.11 Lenz's Law ................................................. 20
2.12 Magnetic Moment ........................................... 21
2.13 Magnetons ................................................... 22
2.14 Flux Driving Force ......................................... 23
2.15 Flux Resisting Force ....................................... 24
2.16 Permeability ................................................. 24
2.17 Types of Moving Charged Particles ....................... 25
2.18 Magnetic Mirror ............................................ 27
ix
x CONTENTS
3. Chemical Effects .................................................... 28
3.1 Force Patterns ................................................ 28
3.2 Minimum Energy ............................................. 29
3.3 Atomic Particles in Path Traverse .......................... 30
3.4 Lenz Opposition ............................................. 31
3.5 Spinning Particles ............................................ 32
3.6 Magnetic Field Effect on Orbit Energy ..................... 34
3.7 Spinning Particle Pairs ....................................... 36
3.8 Unpaired Spinning Particles ................................. 38
3.9 Directional Coherence ....................................... 39
3.10 Magnetization ............................................... 41
3.11 Imposed Field Alignments ................................. 41
3.12 Field Intensity ............................................... 43
3.13 Microenvironment .......................................... 44
3.14 Self-Alignment .............................................. 45
3.15 Individual Opposition ....................................... 46
3.16 Individual Skewed Opposition ............................. 47
3.17 Group Opposition ........................................... 48
3.18 Domain Walls ............................................... 49
3.19 Crystal Restrictions ......................................... 50
3.20 Multiple Domains ........................................... 51
3.21 Phase Transitions ........................................... 52
3.22 Double Lattice .............................................. 53
3.23 Magnetic Anisotropism ..................................... 54
3.24 Susceptance Variations ..................................... 55
3.25 Flux Refraction ............................................. 55
3.26 Spin Waves .................................................. 55
3.27 Magneto-Electric Effect .................................... 57
4. Magnetic Hysteresis ................................................ 60
4.1 Domain Matrix ............................................... 60
4.2 Weak Magnetic Fields ....................................... 61
4.3 Medium Magnetic Fields .................................... 62
4.4 Strong Magnetic Fields ...................................... 63
4.5 Hysteresis Loop.............................................. 63
4.6 Barkhausen Effect ........................................... 65
4.7 Energy Loss .................................................. 66
4.8 Rotational Hysteresis ........................................ 67
4.9 Ancillary Effects ............................................. 67
CONTENTS xi
5. Thermal Effects ..................................................... 69
5.1 Chemical Potential ........................................... 70
5.2 Nerst Effect .................................................. 71
5.3 Magneton Alignments ........................................ 72
5.4 Thermoferromagnetic Effect ................................ 72
5.5 Cabrera-Torroja Effect ...................................... 74
5.6 Thermoferrimagnetic Effect ................................. 75
5.7 Ferromagnetic-Thermoelectric Effect....................... 76
5.8 Decalesence .................................................. 76
5.9 Magnetic Semiconductor Effect ............................. 77
6. Mechanical Effects .................................................. 79
6.1 Ampere's Forces ............................................. 79
6.2 Pinch Effect .................................................. 80
6.3 Magnetic Rigidity ............................................ 80
6.4 Dimensional Changes ........................................ 81
6.5 Ferromagnetic Stiffening .................................... 82
6.6 Mechanical Forcing Fields .................................. 82
6.7 Barnett Effect ................................................ 82
6.8 Maxwell Effect ............................................... 83
6.9 Paramagnetic Tension ....................................... 84
6.10 Havens Balance ............................................. 86
6.11 Paramagnetic Levitation .................................... 86
6. 12 Magno-Therm Effect ....................................... 87
6.13 Ferromagnetic Fluid ........................................ 88
6.14 Relay ......................................................... 89
6.15 Fluid Actuator .............................................. 90
6.16 Ferrofluid ................................................... . 91
6.17 Magnetic Suspension 93
7. Magnetic Measurements ............................................ 94
7. I Field Direction ............................................... 96
7.2 Oscillating Magnet ........................................... 96
7.3 Permanent Magnet "Gauss Meter" ......................... 97
7.4 Gradiometer .................................................. 98
7.5 Vibrating Sample Magnetometer ............................ 99
7.6 Bozorth Configuration ...................................... 100
7.7 Gouy Method ................................................ 101