OTHER: Electrical - Motor - Rotor - Permanent Magnet

• See; Permanent Magnet Motor Technology, Chapter 2 - Permanent Magnet Materials and Circuits.

Br is the measure of its residual magnetic flux density in Gauss, which is the maximum flux the magnet is able to produce. ( 1Gauss is like 6.45 lines/sq in) (1 gauss is equivalent to 10^-4 T), Gauss is an obsolete term.
Hc is the measure of the coercive magnetic field strength in Oersted, or the point at which the magnet becomes demagnetized by an external field. ( 1Oersted is like 2.02 ampere-turns/inch)
BHmax is a term of overall energy density. The higher the number, the more powerful the magnet.
Tcoef of Br is the temperature coefficient of Br in terms of % per degree Centigrade. This tells you how the magnetic flux changes with respect to temperature. -0.20 means that if the temperature increases by 100 degrees Centigrade, its magnetic flux will decrease by 20%!
Tmax is the maximum temperature the magnet should be operated at. After the temperature drops below this value, it will still behave as it did before it reached that temperature (it is recoverable).
Tcurie is the Curie temperature at which the magnet will become demagnetized. After the temperature drops below this value, it will not behave as it did before it reached that temperature. If the magnet is heated between Tmax and Tcurie, it will recover somewhat, but not fully (it is not recoverable).
(please note that this data is from www.magnetsales.com)

• PROPERTIES OF MAGNETIC MATERIALS http://www.astro.uvic.ca/~tatum/elmag/em12.pdf
• Diamagnetic, Paramagnetic, and Ferromagnetic Materials http://www.ndt-ed.org/EducationResources/CommunityCollege/MagParticle/Physics/MagneticMatls.htm
• Ferromagnetism http://en.wikipedia.org/wiki/Ferromagnetic
• FERROMAGNETIC MATERIALS http://www.phys.unsw.edu.au/PHYS2939/pdf/Ferromagnetic_Mats.pdf
• In ferromagnetic materials, small regions with a particular overall spin orientation are termed domains.
• This strong (large) spin alignment leads to huge permeabilities:
• Material Relative Permeability μ_r
• Nickel 250
• Cobalt 600
• Iron (pure) 4,000
• Mumetal 100,000 (aka μ-metal) is an alloy of iron (~25%) and nickel (~75%) + small % of other elements.)
• Paramagnetic metal:
• Aluminium ≈1
• Ferromagnetic Materials http://www.tf.uni-kiel.de/matwis/amat/elmat_en/kap_4/advanced/t4_1_3.html
• MAGNETIC PHENOMENA IN FERROMAGNETIC MATERIALS http://physics-animations.com/Physics/English/mag_txt.htm

• Halbach magnet array; ~
• http://www.tip.csiro.au/Machines/papers/iwscem/index.html
• Build a Halbach array; http://www.matchrockets.com/ether/halbach.html - http://www.otherpower.com/danf/halbach.html
• MAGNETIC FORCES INSIDE PERMANENT MAGNET ASSEMBLIES ~ http://www-sldnt.slac.stanford.edu/nlc/notes/Bowden_Eng/ABC_TechNote-067_2.pdf Have hard copy.
• The Aurora - Solar-powered electric vehicle had an ironless air-gap winding.
• Definition;~ http://en.wikipedia.org/wiki/Halbach_array Have hard copy.
• http://www.gaussboys.com/pages.php?pageid=6
• Halbach array has the following advantages: from [Source ~ AFPM p.111]
• The fundamental field is stronger by a factor of 1.4 than in a conventional PM array, and thus the power efficiency of the machine is doubled.
• The array of PM,s does not require any backing steel magnetic circuit ....
• The magnetic field is more sinusoidal...
• Halbach array has very low back-side fields.
• http://www.cip.csiro.au/Machines/papers/DesignOfAnInWheelMotorForASolarPoweredElectricVehicle(IEE).pdf#search=%22%22laminated%20core%22%20%22permanent%20magnet%22%20layer%20stator%20%22axial%20flux%22%22
• Design and Analysis of High Speed Slotless PM Machine with Halbach Array ~ High speed???
• RC Groups ~ Discussion - Axial flux bldc motor - Looks interesting.

• Stanford Magnets Company.
• China Rare Earth Permanent Magnet Ltd.
• Permanent Magnet Products; http://www.stanfordmagnets.com/magnet.html
• NdFeB: (Neodymium, Iron and Boron) http://www.magnetsales.com/Neo/Neoprops.htm
• Supermagnete

• See; Permanent Magnet Motor Technology, Chapter 2 - Permanent Magnet Materials and Circuits.

• Electrotor-SloMo - Motor - Rotor - Permanent Magnet
• AeroVantage ~ Motor - Transverse Flux - Rotor - Halbach Array

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