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 We supply high-quality magnets in a range of materials, shapes and configurations:
Magnet Materials
- Neodymium Iron Boron (rare earth)
- Ferrite (ceramic)
- Cast Alnico
- Samarium cobalt (rare earth)
(available as part of a magnet assembly or made to order)
If you can't find the magnet you want in its material group it may be in:
Magnet Assemblies
- Magnet assemblies Magnets constructed from more than one material. Usually a metal housing is required to provide extra protection for the magnet material, or to add features which may be impossible to achieve using the magnet material alone e.g. if the magnet needs a tapped screw fitting.
Flexible Magnets
- Flexible magnets Strontium ferrite magnet bound into a flexible thermo-plastic which is then calendered into sheet or extruded into strip.
Neodymium Magnets (rare earth)
Neodymium iron boron (rare earth) is the highest strength magnet material available.
Use where space is it a premium or a very high level of magnetism is required.
The material itself is brittle and has poor corrosion resistance. To counter this it is usually coated or supplied as a magnetic assembly (the magnet material is contained in a metal 'pot' - see our Neodymium magnet assemblies.
Neodymium magnet features:
- High power
- Low maximum operating temperature - 100 degrees
Neodymium magnets are very brittle and must be handled with care. All are anisotropic (the magnet strength is strongest in one direction).
Alloys are available which increase maximum operating temperatures but at the expense of magnet strength. Please contact us for more information about this and custom sizes.
 Blocks
Neodymium block magnets
 Discs
Neodymium disc magnets
 Ring
Neodymium ring magnets
 Pemanent Magnet Handbook
Ferrite Magnets (ceramic)
Often called 'ceramic magnets' because they are hard and brittle like porcelain.
Ferrite magnets are the most widely used magnet type because of their low cost of manufacture and high coercive properties.
Features:
- 250 degrees C maximum temperature
(for higher temperature applications see cast alnico magnets )
- Economical
- High coercivity - do not lose their magnetic properties easily
- Hard and brittle
There are 2 main forms:
Sintered Ferrite
Produced from strontium and has anisotropic properties (the magnet is much stronger along one axis at the expense of other axes). Usually formed by wet pressing. Applications:
- Audio / television
- Holding / clamping
- Loud speakers
- Reed switches
- Security systems
- Sump plugs
- Water conditioners
Bonded Ferrite
Ferrite powders are mixed with polymer based resins. Cheaper to manufacture that sintered. Used for a wide range of electronic and small motors and used extensively in the automotive industry. Applications:
- Instrumentation
- Reed switches
- Sensor applications
- Blocks
- Discs
- Marker / planner (ceramic discs)
- Rings
Pemanent Magnet Handbook
Cast Alnico Magnets
Alnico is a family of materials based on the same mix of elements (ALuminium, NIckel, CObalt and iron).
Varieties of Alnico with different properties are made by mixing these elements in different proportions e.g. Alcomax III
Alnico magnets have the following features:
- High maximum temperature up to 550 degrees C. They are the most suitable magnets for high temperature applications
- Economical
- Very stable
- Good corrosion resistance
Alnico is the most suitable magnet material for complex custom shapes as it can be moulded. Once cast, however, it is so hard that it can only be machined by grinding.
 Bars - cylindrical
Alnico 5 (Alcomax 3) cylindrical magnets with a maximum operating temperature of 550 degrees C.- Bars - rectangular
Can be used in temperatures up to 550 degrees C. North pole indicated by a notch.
- Buttons
Alnico 2 magnets with a maximum temperature of 550 degrees C.
 Center Poles
Cylindrical magnets with central hole. Preferred magnet axis is from one flat face to the other (anistropic) giving more stored magnetic energy for the volume than other designs in the same material.- Channels
- Major
- Minor
 Pocket
Traditional horseshoe shape magnets. Alnico magnet material.- Power
Very powerful (up to 60kg maximum pull) range of magnets. Some with fixing hole / holes.
- Rotor
Multi-pole magnets. Used in synchronous motors, dynamos, air turbines and generators. Alnico 5 (Alcomax III) material with a maximum temperature of 550 degrees C.
Pemanent Magnet Handbook
 Magnet Assemblies
Magnet assemblies are constructed from more than one material.
Usually this consists of one of the above magnet material and a metal coating or housing.
This is to add protection to magnet materials and / or to allow a magnet to be constructed with a feature, such as a screw thread, which is not possible using the magnet material alone.
Pot Magnets
Most of our magnetic assemblies are pot magnets, where the metal housing is an essential part of the magnetic circuit.
The two magnetic poles are concentric and are both on the end face of the magnet.
Pot magnets are the most efficient design for gripping (other designs are preferable for lifting and attracting across air gaps).
Features:
- No stray flux as magnetism is retained in a closed circuit
- The pot screens the magnet material from de-magnetising effects
- Pot is machineable
- Can be inserted into or fitted to, steel without adverse effect (this cannot be done with unscreened magnets)
- The magnet itself is the most efficient magnet shape: plain cylinder magnetised lengthways
- Concentration of flux in the mild steel housing can be twice that of the magnet itself creating increased gripping power
- Distance of magnetic attraction lower than that of other magnets but grip in intimate contact is vastly superior to magnets of similar material and weight but different design.
- Neodymium Magnet Assemblies
Single bi-pole assembly neodymium iron boron magnet with pole pieces encased in an aluminium pot. Neodymium magnets can achieve equal or greater holding forces to larger conventional pot magnets.
 Alnico Deep Pots
Alnico magnet material (Alcomax III to be specific) in a steel pot, some with central tapped fixing hole thread. - Alnico Shallow Pots
Designed for applications where high grip magnets are needed but deep pots are just too deep. They provide good intimate contact grip but are not as stable as deep pots
- Ferrite Heavy Duty Pot
Heavy duty shallow pot magnets made from ferrite (ceramic) material inside a mild steel shell. Offers a high clamping force: the range starts with a magnet with a pull of 25kg. The magnets have a central M6 tapped fixing hole and a removable jacking screw for ease of release.
- Ferrite Magnet With Hook
Ferrite (ceramic) magnet assembly with central tapped fixing hole. Supplied with screw-in hook.
- Ferrite Pots
Ferrite (ceramic) magnet material in a zinc plated housing with central tapped fixing hole. Suitable for attracting, clamping and positioning.
 Ferrite Shallow Pot
Ferrite (ceramic) magnet material with central M6 fixing hole and supplied with removable hook. High clamping force even on painted surfaces and are especially suitable for clamping on thin sheet metal.- Samarium Cobalt
High power magnet assembly. Maxiumum temperature 200 degrees C.
Pemanent Magnet Handbook
 Flexible Magnets
Our flexible magnets are made by binding strontium ferrite magnet into a flexible thermo-plastic binder which is then calendered into sheet or extruded into strip.
Any colour can be achieved by laminating the material.
Colour faced sheet is laminated with a PVC film on the non-magnetic face.
The degree of flexibility depends on the cross section of the profile. All strips can be coiled around a 100mm diameter former without damage.
- Adhesive Backed Magnet
Adhesive backed items are laminated on the non-magnetic face with acrylic-type double sided adhesive and covered with siliconised release paper.
- Extrusion
- Magnetic Tape
- Sheet
Pemanent Magnet Handbook
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