Flexible Magnets


General Information Machining
Manufacturing Methods Magnetizing and Handling
Shapes, Sizes and Grades Available Common Applications for Flexible Magnets
Assemblies Temperature Effects
Surface Treatments Properties of Flexible Magnets

 

Standard Stock Flexible Magnets

Strip

Sheet

 

 

 

General Information

Flexible materials offer the product designer a uniquely desirable combination of properties at lower cost than other magnet materials. The flexibility and machinability of these materials permit design innovations and automated manufacturing techniques not possible with rigid or brittle materials.

Flexible materials can be bent, twisted, coiled, punched, and otherwise machined into almost any shape without loss of magnetic energy.

Higher energy flexible materials may sometimes replace Ceramic 1 materials, if close tolerances are not required, and if operating temperatures are below about 250F. Standard grades of flexible materials have energy products from 0.6 MGOe to 1.6 MGOe.


Manufacturing Methods

Extrusion: to produce materials in strip form (from about 1/4" to 10" wide)

   
Calendering: to produce materials in sheet form (up to about 24" wide)

For both methods, the first step is to form a "compound", which is a wet slurry of powder in the binder material.

Extrusion involves squeezing heated compound through a shaped die, cooling the shaped material as it exits the die, and magnetizing the material. The standard grade materials are only magnetic on one side.

Calendering involves squeezing the compound between rollers to compress and flatten it to form a sheet. The sheet is fed through sets of rollers several times until it reaches the desired thickness. It is then slit to the desired width and magnetized. The standard grade materials are only magnetic on one side.


Shapes, Sizes, and Grades Available

Standard stocked shapes include strip and sheet in the lower energy grades, strip and a variety of punched parts in ring, disc, and bar shapes in the higher energy grades. Non-standard shapes and sizes can be fabricated to blueprint specifications from raw stock. Non-standard profiles of the 0.6 MGOe material can be extruded by fabricating special dies.


Assemblies

Assemblies using metal or other components and magnets can be fabricated by adhering magnets with adhesives to suit a range of environments, by mechanically fastening magnets, or by a combination of these methods. We are able to laminate a variety of standard pressure sensitive adhesives to magnetic strip. Standard adhesives are type "A", for general purpose indoor use, and type "T", for general purpose outdoor use. Type "T" adhesives are formulated for greater resistance to UV effects.


Surface Treatments

No surface treatments are required to protect against corrosion. We are able to laminate a variety of decorative facings to magnetic strip.


Machining

Flexible materials are relatively easy to fabricate: they may be cut, scored, punched, slit, or die cut to shape. We are equipped to fabricate these materials to specification.


Magnetizing and Handling

Low energy flexible magnets are magnetized with multiple poles on one surface to give greater holding force. Higher energy flexible magnets are magnetized either multiple pole, or single pole on one surface. No special handling precautions have to be taken with flexible magnets since they are relatively weak magnetically, and are not brittle.


Temperature Effects

Magnetic properties of flexible magnets degrade linearly with temperature in the same way as Ceramic magnets. However, the limiting factor for flexible magnets are the binder materials used to render them flexible: these begin to flow at temperatures of about 250F.


Common Applications for Flexible Magnets

Flexible magnets are used in a variety of applications from labeling, holding, door gaskets, and signs, to micromotors and CRT focusing. Typical applications: crafts, toys, games, magnetic signs, displays, production control (or visual aid) systems, warehouse shelf labeling, door gaskets, door and cabinet closures, small tool and instrument holders, movable markers, advertising premiums, magnetic business cards, architectural planning layouts, etc.


 

© 2000 Magnet Sales & Manufacturing Company, Inc.