We manufacture and supply Rare Earth Magnets which are offered to our clients at highly competitive prices. These are called "Rare Earth" Magnets because the elements of neodymulum and samarlum are classified in the lanthanides section of the Periodic Table of the Elements. These rare earth magnets are extremely strong for their shapes as rings, blocks and discs.

Neodymium:

Attributes of Neodymium:

• Very high resistance to demagnetization
• High energy for size
• Good in ambient temperature
• High priced
• Material is corrosive and should be coated for long term maximum energy out put
• Low working temperature for heat applications

Application of Neodymium:

• Magnetic separator
• Linear actuators
• Microphone assemblies
• Servomotors
• DC motors (automotive starters)
• Computer rigid disc drives
• Hammer bank printers
• Speakers

Samarium:

Attributes of Samarium:

• High resistance to demagnetization
• High energy (magnetic strength is strong for its size)
• Good temperature stability
• Expensive material (cobalt is market price sensitive)

Applications of Samarium:

• Computer disc drives
• Sensors
• Traveling wave tubes
• Linear actuators
• Satellite systems
• Motors where temporary stability is vital

Rare Earth Tolerances:

For as pressed material, tolerance on the thickness (direction of magnetization) is +/-.127mm. Other Dimensions are +/-2.5% or +/-.254mm, which is greater. As per the Magnet Materials Producers Association (MMPA) standards, visual imperfections such as hairline cracks, porosity and minor chips are commonly found in sintered metallic magnets. A chipped edge is considered acceptable if less than 10% of the surface is missing. Cracks are acceptable as long as they do not extend across more then 50% of pole surface.

Rare Earth Magnetizing and Handling:

As these are brittle and magnetically strong, these can be crucial to handle the magnets with extreme care to avoid personal injury and damage to the magnets. Fingers can be severely pinched between attracting magnets. Magnets can be chip if allowed to “Jump at” an attracting object. It is highly recommended that when constructing rare earth magnetic assemblies, they be magnetized after assembly.

Rare Earth Machining:

As the Rare Earth Magnet material is prone to chipping and cracking, it does not lend itself to conventional machining methods. Moreover, it can be abrasively ground, but only with the use of liberal amounts of coolant. The coolant minimizes heat fracturing and the risk of fires caused by oxidized grinding dust.

Our company manufactures Ferrite Magnet by using strontium carbonate and iron oxide. These ferrite magnets are charcoal gray in color and usually appear in the forms of discs, rings, blocks, cylinders, and sometimes arcs for motors.

Attributes of Ferrite Magnets:

• High intrinsic coercive force
• Tooling is expensive
• Least expensive material compared to alnico and rare earth magnets
• Limited to simple shapes due to manufacturing process
• Lower service temperature than Alnico, greater than rare earth
• Finishing requires diamond cutting or grinding wheel
• Lower energy product than alnico and rare earth magnets
• Most common grades of ferrite are 1,5 and 8 (1-8 possible)
• Grade 8 is the strongest ferrite material available

Applications:

• Speaker magnets
• DC brush less motors
• Magnetic Resonance Imaging (MRI)
• Magnetos used on lawnmowers, and outboard motors
• DC permanent magnet motors (used in cars)
• Separators (Separate ferrous material from non-ferrous)
• Used in magnetic assemblies designed for lifting, holding, retrieving and separating

Tolerances:

• Pressed dimensions are either +/- 2% or +/- 0.5mm whichever is greater
• Cut dimension are either +/- 3% or +/-0.5mm, whichever is greater
• Thickness tolerances are normally ground to +/- 0.1mm
• Visual imperfections such as cracks, porosity, voids, surface finish (commonly found in sintered ceramic magnets) do not constitute cause for rejection.

Magnetizing and Handling:

• Material of Ferrite Magnet is extremely brittle and can chip or breakable if dropped on a hard surface, or if allowed to “Jump at” on attracting object
• The weakest grade of ceramic material is grade 1, which is typically non-oriented
• Grades 5 and 8 are oriented ceramic material
• Grade 8 is the strongest ceramic magnet material available
• When making magnetic assemblies with ferrite, it is typically easier for production purposes to magnetize the product after assembly.

Machining:

Since ferrite material is so brittle, it requires special machining techniques and equipment. We are fully equipped to cut and grind ceramic material to customers’ specifications.

We are engaged in manufacturing Alnico Magnets by using aluminum, nickel, cobalt, copper, iron and sometimes titanium. These alnico magnets can be either cast or sintered and are available at market leading prices.

Cast Alnico:

Cast Alnico is melted and poured into a mold for solidifying. Once solidified, the material is rough ground and then heat-treated and cooled, sometimes in a magnetic field. The magnet is called anisotropic when it is treated in the presence of a magnetic field.

The material is oriented by this to take on maximum magnetization and allows a higher gauss level. Whereas, the cast magnet that is not heat-treated in a magnetic field is called Isotropic. The material can be ground to specific tolerances and then magnetized after heat treatment and cooling

Sintered Alnico:

Sintered Alnico is made from a powdered mixture of ingredients which are pressed into a die under tons of pressure, sintered in a hydrogen atmosphere and then cooled either within a magnetic field or without (anisotropic Vs Isotropic).

Attributes of both Cast and Sintered Alnico:

• Very temperature stable, great for high heat applications.
• Maximum working temperature 525 C -550 C
• May be ground to size
• Does not lend itself to conventional machining (Hard and Brittle)
• High residual induction and energy product compared to Ferrite material
• Low coercive force compared to Ferrite and rare earth materials (more subject to demagnetization)
• Most common grades of Alnico are 5 and 8

Applications:

• Magnetos
• Separators
• Sensors
• Electron tubes
• Traveling wave tubes
• Radar
• Holding magnets
• Coin acceptors
• Clutches and bearings
• Motors
• Distributors
• Relays
• Controls
• Generators
• Receivers
• Telephones
• Microphones
• Bell ringers
• Guitar pickups
• Loudspeakers
• Security systems
• Cow magnets

Magnetizing and Handling:

Magnetizing is done after the magnet has been machined to the correct tolerances. The Alnico material is brittle and can chip or break if dropped on a hard surface. Also, because it has a low resistance to demagnetization and will lose power if it is stored improperly (poles repelling each other). For best results, store magnetized Alnico so that pieces are attracting each other, or with a steel keeper.

Machining:

Being a hard and brittle material, it does not lend itself to conventional machining.