Check this thread frequently. I keep adding new links to existing messages.
================================================================

New thread to hold all those references that are scattered throughout the forum. I'll start things off with a few things I found. Please contribute anything else you think is relevant.

Let's make this thread into something we would all want to come back to, day after day. Just the relevant information.

Here's some college-level materials
==============================

COLLEGE COURSES and MATERIALS

MIT Magic Of Magnets
http://ocw.mit.edu/OcwWeb/Materials-Science-and-Engineering/3-A08Fall-2005/CourseHome/index.htm

MIT Magnetic Materials
http://ocw.mit.edu/OcwWeb/Materials-Science-and-Engineering/3-45Spring2004/CourseHome/index.htm

MIT Electromagnetic Theory (2002)
http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-630Electromagnetic-TheoryFall2002/CourseHome/index.htm

MIT Electromagnetic Theory (2005)
http://ocw.mit.edu/OcwWeb/Physics/8-02TSpring-2005/CourseHome/index.htm

MIT Electromagnetic Wave Theory
http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-632Electromagnetic-Wave-TheorySpring2003/CourseHome/index.htm

MIT Advanced Electromagnetism
http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-635Advanced-ElectromagnetismSpring2003/CourseHome/index.htm

MIT Electricity and Magnetism
http://ocw.mit.edu/OcwWeb/Physics/8-02TSpring-2005/CourseHome/index.htm

MIT Electricity and Magnetism II
http://ocw.mit.edu/OcwWeb/Physics/8-022Fall-2004/CourseHome/index.htm

MIT Electricity and Magnetism II: with Experimental Focus
http://ocw.mit.edu/OcwWeb/Physics/8-02XSpring-2005/CourseHome/index.htm

MIT Electromagnetic Fields, Forces, and Motion
http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-641Spring-2005/CourseHome/index.htm

MIT Superconducting Magnets
http://ocw.mit.edu/OcwWeb/Nuclear-Engineering/22-68JSpring2003/CourseHome/index.htm

MIT Electromagnetic Interactions
http://ocw.mit.edu/OcwWeb/Nuclear-Engineering/22-105Electromagnetic-InteractionsFall1998/CourseHome/index.htm


Work from Magnetic Hysteresis Curves
http://ocw.mit.edu/NR/rdonlyres/Materials-Science-and-Engineering/3-014Fall-2005/1949B24F-E76F-40BE-B22E-A79CFB72DFE9/0/b3.pdf

Magnetic Work
http://ocw.mit.edu/NR/rdonlyres/Materials-Science-and-Engineering/3-014Fall-2005/5E25DE90-B7BE-4202-85F3-A26FA6E51782/0/a1_mag_work.pdf

Magnetic Fundamentals
http://ocw.mit.edu/NR/rdonlyres/Materials-Science-and-Engineering/3-15Fall2003/8AE95115-7CD1-4F6A-951F-D74A31FFA5D4/0/ho9_magnetic_fundamentals.pdf

BASIC MAGNETISM REFERENCES
===========================

Magnet Applet (animation)
http://web.mit.edu/jbelcher/www/java/lev_mag/lev_mag.html

Fundamentals of Magnetism & Hysteresis Simulation
http://www.allegromicro.com/techpub2/dexter/science.htm

Magnetic Phenomena in Ferromagnetic Materials
http://physics-animations.com/Physics/English/mag_txt.htm

Hysteresis Calculation
http://www.bama.ua.edu/~tmewes/Java/Reversal/reversal.shtml

Ferromagnetism
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/ferro.html

Hysteresis
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/hyst.html

Permanent Magnet Materials - Standards
http://www.intl-magnetics.org/pdfs/0100-00.pdf

Magnet University
http://www.rare-earth-magnets.com/magnet_university/magnet_university.htm

Magnetic Materials
http://www.aacg.bham.ac.uk/magnetic_materials/

Permanent Magnet Design Guide
http://www.magnetsales.com/Design/DesignG.htm

Magnetics Technology Center
http://www.arnoldmagnetics.com/mtc/mtc_applications.htm

Magnetism and Electromagnetism
http://www.ibiblio.org/obp/electricCircuits/DC/DC_14.html

Magnetic Domains
http://units.aps.org/units/dmp/gallery/domains.cfm

Magnetic Materials
http://www.phys.unsw.edu.au/PHYS2939/pdf/Magnetic_Materials.pdf

Ferromagnetic Materials
http://www.phys.unsw.edu.au/PHYS2939/pdf/Ferromagnetic_Mats.pdf

Magnetic Circuits
http://www1.gantep.edu.tr/~koc/EP331Lecture/lec13.pdf

Hysteresis
http://www.lassp.cornell.edu/sethna/hysteresis/hysteresis.html

Permanent Magnet Guidelines
http://www.duramag.com/pdfs/MMPA_PMG-88.pdf

Permanenjt Magnet Design
http://www.magnetweb.com/design2.htm

Bar Magnet Calculator
http://www.integratedsoft.com/papers/benchmark/bar_magnet/calculator.asp


(edit: added a few more links)

MAGNETIC VISCOSITY

Magnetic Viscosity
http://depts.washington.edu/kkgroup/publications/PDF/2001_Krish_NdFeB_alloys.pdf

Magnetic Viscosity
http://rsnz.natlib.govt.nz/volume/rsnz_28/rsnz_28_00_001320.pdf

Some Magnetic references within a good basic on physics:

http://theory.uwinnipeg.ca/mod_tech/tech.html


excellent thread, and thanks for those links.

Google Video links to some good physics lectures..
http://video.google.com/videosearch?q=owner%3Aucberkeley+physics+10&page=1&so=2

what a good idea...thanks

Sean or anyone from Steorn.. any chance of making this a sticky.

Ta!

Free MIT OpenCourseWare

6.013 / ESD.013J Electromagnetics and Applications, Fall 2005

http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-013Fall-2005/CourseHome/index.htm

Magnetics Software

MagNet
http://www.integratedsoft.com/papers/benchmark/bar_magnet/calculator.asp

FEMM
http://femm.foster-miller.net/wiki/HomePage

QuickField
http://www.quickfield.com/free_soft.htm

Flux (free 60 day evaluation)
http://www.magsoft-flux.com/Products/Flux/

Vizimag Software
http://www.vizimag.com/ordering.htm for visualizing magnetic fields (30 day free trial)
---------------------------------------------
There's also a book (with v1 source code) available explaining how it works (seems expensive at £60 new, but it does come with source code).

Good links on the calculator page (scroll down)
----------------------------------------------
(thanks for this thread overconfident )

Good idea and useful resources.

Make it sticky please.

excellentover confident

THEORIES and PAPERS:

(Following links submitted by Emeraldsong in Kinetica thread)
Theory of spin-transfer torques in magnetic nanostructures
http://www.physics.nist.gov/Divisions/Div841/Gp3/Projects/Theory/theory_transfer.html

Statistical Properties of Pinning Fields
http://arxiv.org/PS_cache/cond-mat/pdf/0605/0605340.pdf

Domain Nucleation and Annihiliation
http://arxiv.org/ftp/cond-mat/papers/0612/0612383.pdf

Magnetic Reconnection
http://en.wikipedia.org/wiki/Magnetic_reconnection

======================================================

Magnetization Reversal Dynamics
(contributed by vibrator - German web page, but paper is in english)
http://www.diss.fu-berlin.de/2005/309/


=============================================================

Introduction to EMR
(link contributed by boomerang)
http://www.mariner.connectfree.co.uk/html/emr.htm

=============================================================

Magnetic Materials
(contributed by jcims and capeguy)
http://www.aacg.bham.ac.uk/magnetic_materials/

=============================================================

Magnetic Viscosity
http://depts.washington.edu/kkgroup/publications/PDF/2001_Krish_NdFeB_alloys.pdf

Magnetic Viscosity
http://rsnz.natlib.govt.nz/volume/rsnz_28/rsnz_28_00_001320.pdf

Effects of Stacking Faults on Magnetic Viscosity
http://www-ssrl.slac.stanford.edu/materialscatter/pubs/jappl_phys_85_2775.pdf

Magnetic Field Instabilities
http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1984ApJ...277..312S&data_type=PDF_HIGH&type=PRINTER&filetype=.pdf

Activation Entropy, Activation Energy, and Magnetic Viscosity
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1007&context=physics_kirby

Coercivity Analysis (discusses Barbier Plot)
http://www.physics.udel.edu/~yzhang/published%20paer/MICHELL_PHYSTASOL_193.pdf

Investigation of the Magnetic Viscosity Parameter (Barbier Plot)
http://ftp.physics.uwa.edu.au/pub/Theses/PhD/1997_Crew_600dpi.pdf

The Influence of Magnetic Viscosity (Barbier Plot)
http://joam.infim.ro/JOAM/pdf6_2/Grossinger.pdf

Relaxation of Thermo-Remanent Magnetization
http://arxiv.org/PS_cache/cond-mat/pdf/0505/0505145.pdf

Connection between Hysteresis and Thermal Relaxation
http://arxiv.org/PS_cache/cond-mat/pdf/9910/9910108.pdf

Anomalous Magnetic Viscosity
http://www.physics.nus.edu.sg/~phyfyp/reprint/ypf9907.pdf

Giant Magnetic Viscosity in SmCo
http://magnet.atp.tuwien.ac.at/publications/jap/tellez_1999_86_5157.pdf

Activation Volumes in Thin Film and Particulate Systems
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1005&context=physics_kirby

Time-Temperature Relations in Magnetization
http://www.nature.com/nature/journal/v286/n5770/pdf/286245a0.pdf

Subatomic Movements of a Domain Wall
http://www.nature.com/nature/journal/v426/n6968/pdf/nature02180.pdf

Magnetism of Nanometer-Scale Iron Particles Array
http://dns.ntu-ccms.ntu.edu.tw/references/J_APPL_PHYS-85-5249-1999.pdf

Magnetic Ordering and Anisotropies of Atomically Layered FeAu
http://kluedo.ub.uni-kl.de/volltexte/1999/964/pdf/no_series_69.pdf

Magnetic Field Scaling of Relaxation Curves in Small Particle Systems
http://arxiv.org/PS_cache/cond-mat/pdf/0106/0106167v1.pdf

Magnetic Particles
http://arxiv.org/PS_cache/cond-mat/pdf/9806/9806082.pdf

Sweep Rate and Magnetic Viscosity Dynamics
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1004&context=physics_kirby

Viscosity in Hard Magnetic Materials
http://www.ifp.tuwien.ac.at/forschung/alfa/reports/vienna_report/viscosityrg.pdf

Initial and Four-Quadrant BH Curve of Soft Magnetic Materials
http://www.walkerldjscientific.com/Products/Product_Lines/Magnetic_Analysis/Hysteresisgraphs/Initial-4-Quadrant.pdf

Metallic Magnetic Heterostructures
http://www.dspace.cam.ac.uk/bitstream/1810/34608/1/thesis.pdf

Saturation in Textured Soft Magnetic Materials
http://mimp.materials.cmu.edu/papers/2001_28.pdf

Time Dependent Entropy Evolution ... Electromagnetic Relaxation
http://boulder.nist.gov/div818/81801/properties/Publications/Baker-Jarvis%20PR%2005.pdf

Magnetic Systems
http://www.atp.ruhr-uni-bochum.de/rt1/currentcourse/node116.html

Nonlocal Magnetization Dynamics
http://www.tn.tudelft.nl/tn/Lectures/Meso/TserkovnyakRMP.pdf

Comments on Energy Stored in Permanent Magnets
http://www.magnequench.com/tech_resources/tech_center/reference/papers/comments_energy_in_mag.pdf

(Max size reached - continued in another message below)

Mechanics (A Review) - in a Physics Forum.. excellent general reference.
http://forum.physorg.com/index.php?showtopic=3761

Edit: The Magnetics section is near the bottom of the first page.

Giant Magneteoresistance and Ohms Law (this is where its at)

http://www.trt.thalesgroup.com/ump-cnrs-thales/umr-0137/oral/transport_course_2005-1.pdf

Books concerning same

http://www.trt.thalesgroup.com/ump-cnrs-thales/umr-0137/oral/transport_course_2005-1.pdf

a very basic introduction to Magnet Therapy & Acupuncture

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160066653148&ssPageName=ADME:B:EOIBSA:UK:11

www.rareearth.org great information



http://www.rareearth.org/permeability_and_saturation.htm

This link currently APPEARS to answer the question that had many of us tearing our hair out for a week or so.



< http://www.mariner.connectfree.co.uk/html/emr.htm >

Energy stored on Permanent magnets

http://www.magnequench.com/tech_resources/tech_center/reference/papers/comments_energy_in_mag.pdf



Cogging Torque Reduction in a Permanent Magnet Wind Turbine


http://www.nrel.gov/docs/fy02osti/30768.pdf


Fun With Magnets

http://www.magma.ca/~dougdela/physics/magnets04.pdf



and for the disbelievers

http://my.execpc.com/%7Erhoadley/magfree.htm

Almost 1,000 links for magnetism

http://del.icio.us/search/?fr=del_icio_us&p=magnetism&type=all&setcount=100

I'm only a twentieth of the way reading through all this stuff! When is the exam?

A simple visualization on how magnetic "shields" work.
The term "shield" is somewhat misleading. A magnetic shield, neither stops nor bounces magnetism.
Rather, a magnetic shield concentrates magnetic field lines from the surrounding area and redirect them along/through the shield's body. Shield effectiveness for a specific application is ofc dependent, on its physical dimensions, and its magnetoelectric properties.

Couple of demonstrative pics:

< http://tpub.com/neets/book1/chapter1/1j.htm >

... continued:
THEORIES and PAPERS:

Larmour Precession
(contributed by Kent767)
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/larmor.html

Coercivity Analysis in Magnets with Abnormal Temperature Behavior
(contributed by sb2020)
http://www.physics.udel.edu/~yzhang/published%20paer/MICHELL_PHYSTASOL_193.pdf

Magnetic Dipoles, Hysteresis, and Core Losses
(contributed by mo)
http://www.ep2000.com/Templates/white%20papers/MagneticDipolesEP.pdf

Possibly Spurious Signals from Magnetic Viscosity
(contributed by boomerang)
http://www.elcometer.com/international%20index%20pages/international/Concrete/technical%20notes/A10.htm

Forty Years of Magnetism
(contributed by boomerang)
http://hal.archives-ouvertes.fr/docs/00/05/39/82/PDF/Neel40years_English.pdf

Hitchhikers Guide to Magnetism
(pinestone contributed a couple sections, this is the whole guide in PDF)
http://www.irm.umn.edu/hg2m/hg2m.pdf

Applications of Maxwell's Equations

url/ http://www.sfu.ca/physics/associate/emeriti/cochran/MAX.pdf \url

B. Van Waeyenberge et al.,
Magnetic vortex core reversal by excitation with short bursts of an [very weak] alternating field.
http://www.nature.com/nature/journal/v444/n7118/full/nature05240.html
http://www.mf.mpg.de/de/abteilungen/schuetz/index.php?content=groups&type=specific&name=agstoll

Design and preparation of a bulk magnet exhibiting an inverted hysteresis loop
http://prola.aps.org/abstract/PRB/v64/i13/e132404

very interesting
[url]http://www.tf.uni-kiel.de/matwis/amat/elmat_en/index.html[/url]

nephry,
I can't afford to buy the article on the magnet with the reverse hysteresis loop that you referenced above. Could you give a brief summary?

Bluebeard23:nephry,
I can't afford to buy the article on the magnet with the reverse hysteresis loop that you referenced above. Could you give a brief summary?

I didn't have any problem, it was free: here's a little of it:

"What happens if we apply an external field to a ferromagnet with its equilibrium domain structure?
The domains oriented most closely in the direction of the external field will gain in energy, the other ones loose; always following the basic equation for the energy of a dipole in a field.
Minimizing the total energy of the system thus calls for increasing the size of favorably oriented domains and decreasing the size of unfavorably oriented ones. Stray field considerations still apply, but now we have an external field anyway and the stray field energy looses in importance.
We must expect that the most favorably oriented domain will win for large external fields and all other domains will disappear.
If we increase the external field beyond the point where we are left with only one domain, it may now even become favorable, to orient the atomic dipoles off their "easy" crystal direction and into the field.
After that has happened, all atomic dipoles are in field direction - more we cannot do. The magnetization than reaches a saturation value that cannot be increased anymore."

"...the most favorably oriented domain will win...

WTF does that mean?

The more domains there are, the more domain walls there are. The overall domain wall "surface" area increases exponentially. If you rapidly vary the external field between enough field strength to reduce the magnet to one domain and low enough field strength to devolve into many domains what happens to the difference between more PE in the multidomain state and less PE in the single domain state? You know, walking it around the hysteresis loop? The frequency of the field switching would be dependent on the lag time of the magnetic material.

The domain that is already pointed most closely in alignment with the field takes the least amount of energy to move is the one that will increase in size, the domains that are furthest from alignment will decrease in size. But if that's the case, what happens if the magnet is spinning and the domains are constantly changing their alignment?

Magnetization Simulation
http://simscience.org/crackling/Advanced/Magnets/MagnetSimulation.html

Permanent Magnet Theory (several documents including the one below)
http://www.permagsoft.com/english/html/theory.html

Demagnetization Curve (BH Curve)
http://www.permagsoft.com/english/assets/applets/DemagnetisingCurve.pdf

Magnetic Principles Course
http://www.consult-g2.com/course.html

Design of Basic Electro-Mechanical Devices
http://www.me.berkeley.edu/ME229/

Hall Effect Sensors (magnetic field sensors)
http://content.honeywell.com/sensing/prodinfo/solidstate/technical/hallbook.pdf

Properties of Permanent Magnet Materials
http://www.magtech.com.hk/rare_earth.htm

interesting use of magnets. (adsitt ramp)
http://www.theverylastpageoftheinternet.com/magneticExp/adsitt/adsittindex.htm
http://www.theverylastpageoftheinternet.com/menu/adsitt.htm

History of magnets from my old university:

http://www.tcd.ie/Physics/Schools/what/materials/magnetism/two.html

Interesting topic
a suggestion from Dr. Mike

"Unlike forces due to the pressure of an ideal gas, an area element in the electromagnetic field also feels a force in a direction that is not normal to the element. This shear (rather than pressure) is given by the off-diagonal elements of the stress tensor." -wiki

http://en.wikipedia.org/wiki/Maxwell_stress_tensor

http://www.nhn.ou.edu/~shaferry/41832005_files/l4.pdf

pinestone:

Bluebeard23:nephry,
I can't afford to buy the article on the magnet with the reverse hysteresis loop that you referenced above. Could you give a brief summary?

I didn't have any problem, it was free: here's a little of it:

"What happens if we apply an external field to a ferromagnet with its equilibrium domain structure?
The domains oriented most closely in the direction of the external field will gain in energy, the other ones loose; always following the basic equation for the energy of a dipole in a field. ....."

pinestone, the quote you give is not part of the article
"Design and preparation of a bulk magnet exhibiting an inverted hysteresis loop".

Here is one excerpt:

"The objective of the present study is to design a magnet
exhibiting an anomalous magnetic hysteresis loop. Usually,
magnets possess positive values of a remanent magnetization
and a coercive field. Recently, however, a negative remanent
magnetization [i.e. the remaining magnetization is opposed to the original inducing field, comment nephry] was observed in specific exchange-coupled
multilayers such as Co/Pt/Gd/Pt and in epitaxial Fe films on
W(001). These hysteresis loops are called inverted magnetic
hysteresis loops. In these materials, their thin film
forms play an important role in the origin of the unusual
hysteresis loops, and hence, one has considered that these
phenomena are limited to thin-film-type of magnetic materials.

In the present study, however, we try to obtain a bulk
magnet showing such an inverted magnetic hysteresis loop.
The key to designing this unusual magnet is to utilize a
competing effect between the sublattice magnetization
rotation due to the spin-flip transition and the trapping
effect due to the uniaxial magnetic anisotropy"

And of course they succeeded, as:

"... the magnetization became negative in the decreasing part
when the applied field was still positive, while the magnetization
became positive in the increasing part when the
applied field was still negative. The inverted magnetic hysteresis
loops were thus observed in these compositions.
[at a temperature of 2K !, comment nephry] ...
This experimental hysteresis loop qualitatively corresponds
to the calculated hysteresis loop, ..."

The Coefficient of Magnetic Viscosity
http://gita.grainger.uiuc.edu/IOPText/0305-4608/14/8/005/jfv14i8pL155.pdf

Coefficient of Magnetic Viscosity II
http://gita.grainger.uiuc.edu/IOPText/0305-4608/16/7/006/jfv16i7pL145.pdf

A Study of Magnetic Viscosity
http://gita.grainger.uiuc.edu/IOPText/0370-1298/62/9/303/prav62i9p562.pdf

Ferromagnetic After-Effect in Mumetal
http://gita.grainger.uiuc.edu/IOPText/0508-3443/10/3/308/bjv10i3p142.pdf

Single Domain Inclusion Theory of Magnetic Hysteresis
http://gita.grainger.uiuc.edu/IOPText/0370-1328/73/3/420/prv73i3p517.pdf

Magnetic Processes in Weak and Moderate Fields
http://gita.grainger.uiuc.edu/IOPText/0370-1328/84/5/301/prv84i5p625.pdf

Ferromagnetism and Hysteresis
http://gita.grainger.uiuc.edu/IOPText/0959-5309/42/5/301/prv42i5p355.pdf

Common Misapprehension of the Theory of Induced Magnetism
http://gita.grainger.uiuc.edu/IOPText/0959-5309/45/1/308/prv45i1p82.pdf

A New Treatment of Electric and Magnetic Induction
http://gita.grainger.uiuc.edu/IOPText/0959-5309/52/5/301/prv52i5p577.pdf

Adiabatic Temperature Changes Accompanying Magnetization of Iron
http://gita.grainger.uiuc.edu/IOPText/0959-5309/55/3/303/prv55i3p188.pdf

Lines of Force Through Neutral Points in a Magnetic Field
http://gita.grainger.uiuc.edu/IOPText/0959-5309/59/1/303/prv59i1p14.pdf

High Frequency Permeability of Ferromagnetic Materials
http://gita.grainger.uiuc.edu/IOPText/0370-1301/63/10/306/prbv63i10p783.pdf

Magnetic Viscosity in Platinum Cobalt
http://gita.grainger.uiuc.edu/IOPText/0370-1301/66/9/411/prbv66i9p805.pdf

Mathematical Models of Hysteresis
http://www.osti.gov/bridge/servlets/purl/639798-0Imed8/webviewable/639798.pdf

Mathematical Models of Hysteresis (progress report)
http://www.osti.gov/bridge/servlets/purl/10117474-FLJj7W/native/10117474.pdf

Reptation Model for Magnetic Materials
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A443997&Location=U2&doc=GetTRDoc.pdf

High Performance Soft Magnetic Laminates
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A430916&Location=U2&doc=GetTRDoc.pdf

Magnetic Materials - Novel Phenomena and Advanced Characterization
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A418228&Location=U2&doc=GetTRDoc.pdf

Magnetic Materials (1985)
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A154679&Location=U2&doc=GetTRDoc.pdf

Mathematical Models for Electrical and Magnetic Fields
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=0670961&Location=U2&doc=GetTRDoc.pdf

High Temp High Performance Permanent Magnet Materials
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A382940&Location=U2&doc=GetTRDoc.pdf

Permanent Magnet Circuit Design Primer (magnetic circuits)
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=A311457&Location=U2&doc=GetTRDoc.pdf

http://www.magnet.fsu.edu

Modification of Electric and Magnetic Fields by Materials

url/ http://www.fieldp.com/cpa/cpa02.pdf \url

http://www.educypedia.be/electronics/electricitymagneticmat.htm

Reference and Design Manuel....magnets

url/ http://www.dextermag.com/uploadedFiles/Reference_Design_Manual.pdf \url

WHY DO MAGNETIC FORCES DEPEND ON WHO MEASURES THEM?
David N. Jamieson PhD.
School of Physics
University of Melbourne


[url]http://www.ph.unimelb.edu.au/~dnj/teaching/160mag/160mag.htm[/url]


Snipped from a paragraph at the bottom of the article

[color=green][i]In a copper wire with a cross sectional area of 1 square millimetre and carrying a current of 10 Amps the formula for v given above shows that the electron velocity is only 0.7 millimetres per second. This is an extremely small velocity! The Lorentz contraction for such a small velocity differs from 1 by only 3´10-24. This unimaginably small contraction is nevertheless sufficient to cause a slight imbalance in the positive and negative charge densities of the wire that causes moving charged particles to feel a magnetic force. [/i]

NOTE: When these UIUC links were posted, they were freely accessible. It appears they have now been secured and a university account is required now. I have checked my download archives and I apparently did not save copies while I had free access. Sorry. (3/22/07)

A Note on Magnetic Viscosity in Alnico
http://gita.grainger.uiuc.edu/IOPText/0370-1301/62/2/108/prbv62i2p141.pdf

Time Decrease of Magnetic Permeability in Alnico
http://gita.grainger.uiuc.edu/IOPText/0370-1301/63/7/305/prbv63i7p509.pdf

Torque Curves and Other Magnetic Properties of Alcomax
http://gita.grainger.uiuc.edu/IOPText/0370-1301/64/7/302/prbv64i7p549.pdf

Torque Curves and Other Properties of Permanent Magnet Alloys
http://gita.grainger.uiuc.edu/IOPText/0370-1301/65/3/309/prbv65i3p229.pdf

Influence of Heat Treatment on Magnetic Viscosity in Permanent Magnet Alloys
http://gita.grainger.uiuc.edu/IOPText/0370-1301/65/6/115/prbv65i6p461.pdf

Magnetic Viscosity under Discontinuously and Continuously Variable Field Conditions
http://gita.grainger.uiuc.edu/IOPText/0370-1301/65/9/305/prbv65i9p679.pdf

Influence of Temperature on Magnetic Viscosity
http://gita.grainger.uiuc.edu/IOPText/0370-1301/68/6/303/prbv68i6p345.pdf

Comparison of Magnetic Viscosity in Isotropic and Anisotropic High Coercivity Alloys
http://gita.grainger.uiuc.edu/IOPText/0370-1301/69/12/302/prbv69i12p1189.pdf

Unusual Magnetic Properties of Quenched Alcomax III
http://gita.grainger.uiuc.edu/IOPText/0370-1301/70/9/302/prbv70i9p823.pdf

http://www.consult-g2.com/course/chapter1/chapter.html

minor loops:
'On the other hand, if H had been increased negatively somewhat more, moving the B-H point around the knee of the curve, then when H returns toward zero the line does not follow the major loop, but instead moves inward, along a line with the same slope as the major loop, that is, at the recoil permeability slope. The B-H point is now inside the main curve, on what is called a minor loop.'

normal and intrinsic BH curves:
'The set of curves described so far are the so-called normal curves. These are the curves to be used for magnetics design. Another set, called the intrinsic curves, are usually published along with them and are used for scientific purposes (Figure 1.10).'

http://www.aacg.bham.ac.uk/magnetic_materials/hysteresis.htm

from a HK comment:

reference to the conservation of mechanical energy here:

http://www.glenbrook.k12.il.us/gbssci/phys/CLass/energy/u5l2bb.html

Remember Sean talking about the roller coaster?
I bet crank would remember what the amusement park is called

pinestone beat me to that one...

I've used glenbrook's website for a lot of stuff. Being geared for K-12 it's written in VERY approachable langauge and examples.

There is a ton of stuff other than just that page, a whole series of physics atuf for the "beginner" as it were...I love it...lol

http://www.lightandmatter.com/

For general physics to ~1st year undergrad level. Better written than some 'real' textbooks.

The roller coaster is a great analogy. Did anyone see the FEMM animation that Sveintune posted yesterday showing a path Through the fields of four magnets that results in OU?

The magnets were arranged:

# #
# # # (take the bottom right and bottom left magnets and
superimpose them on each other to twist it around
into a circle.)

The magnet on the rotor has to be on a hinged stalk or on the end of a piece of antenna wire or something so that it has a little bit of vertical axis as well as the horizontal circular axis to operate in.

It is repelled by the first magnet up to the second magnet where it is attracted, reaches saturation and is then repelled down to the third, repelled up and etc. all the way around. Works in theory according to Sveintune. I'm going to try and make a model this weekend and experiment to see what speed it needs to go to achieve a self-sustaining cycle.

Note how this cycle produces a roller coaster motion.

Sorry about the formatting. The top magnets are supposed to be in the spaces in between the bottom 3 magnets.

Antiferromagnetic exchange spring:

http://www-als.lbl.gov/als/science/sci_archive/91antiferromagnetic.html