Plastic-Bound Magnets

Tridelta Magnetsysteme

In addition to these magnets, Tridelta also offers flexible magnetic rubber.

Magnetsystem - Magnetsysteme - Hysteresebremse - hysteresebremse drehmoment - Magnetkupplung
 

Product Description

Plastic-bound magnets can be made with narrow geometric tolerances without cost-intensive post-processing. A wide range of forms allow new technical solutions due to the enormous constructive freedom of design.

properties/advantages

  • End dimension-generation manufacture
  • High variety of forms
  • Good corrosion resistance

magical production

Plastic-bound magnets are produced by a press procedure in which the alloy powder is mixed with synthetic resin, pressed and then hardened at approx. 150 ° C. A special process achieves high levels of filling with good mechanical strength despite the lowest plastic components.

Another possibility of making plastic-bound magnets is to compound the powder with plastics and the subsequent spraying. With this method, the heat treatment process is skipped. When casting, the magnetic powder is mixed in a container and poured in the same way as plastic. High tool costs can arise for this manufacturing process, but allows for complicated forms and close tolerances. Compared to sintered magnets, the magnetic values are lower in this process.

Finally, a coating as corrosion protection can be attached in both procedures.

The strand press enables unlimited magnetic lengths. However, the energy product is flexible magnets under the sintered magnets.


magnetic forms

In the case of pressed magnets, all shapes that can be manufactured can be realized: cuboids, cylinders, rings, segments and other molded parts are available. Bores, depressions, grooves, etc. can also be carried out when they run parallel to the press direction.

For sprayed magnets, all forms that can be formable injection technically can be produced. The dimensional tolerances achievable here are very tight, so that rework can be eliminated. For example, waves can be pressed in in tightly tolerated holes. With this magnetic form process, it is also possible to incorporate foreign parts such as magnetic recess parts, etc.


application areas

Extract from the numerous applications:

  • sealing lips, for example for refrigerators and shower
  • magnet tablets/display boards
  • advertising foils, magnetic signs
  • toys, electronics and sensor technology
  • automotive production
  • automation
  • communication technology
  • in machine tools for controlling magnetic switch
  • position recording, angle or path length measurements
  • household appliances
  • electrical industry

temperature behavior

As with the pure varieties of materials, in the case of plastic-bound magnets, temperature influences cause a changed magnetic behavior that depends on the magnetic material.

The maximum operating temperature also depends on the magnetic material and the binder used.


chemical and mechanical properties

The chemical and mechanical properties are determined by the choice of plastic and the plastic content. The density depends on the level of filling. Since the mechanical strength essentially determines the plastic framework, a low plastic content with higher magnetic powder content is synonymous with low strengths with high residual magnetizations. A compromise must often be found between the magnetic and mechanical values, depending on the form.


magnetic properties

Plastic-bound magnets have lower magnetic values than the pure types of materials with which they are mixed, but in some cases significantly wider shape options. In addition, filler orientation and filler shares influence the magnetic properties.

Werkstoff1)HerstellungMax. magnet. Energiedichte
(BH)max
[kJ/m3]
>
Remanenz- flussdichte
Br
[mT]
>
Koerzitiv-
feldstärke

HcB
[kA/m]
>
Koerzitiv-
feldstärke

HcJ
[kA/m]
>
Rel. perm.
Permeabilität

µp
[-]
>
Einsatztemp.2)
Tmax
[°C]

Temp.-
koeff.
TK(BR)
[%/K]

Temp.-
koeff.
TK(HcJ)
[%/K]

Sättigungs-
feldstärke

Hs
[kA/m]
Hartferrit 5/18 pi51751101801,0580-0,20,41000
Hartferrit 7/14 pi6,51951001401,0580-0,20,41000
Hartferrit 11/22 pi112401502201,0580-0,20,41000
Neolit SP 280i284203006501,15110-0,130,4>3000
Neolit SP 445i44,55303507201,15120-0,13-0.4>3000
Neolit NQ 1Ap7063042512001,15110-0,13-0.4>3000
Neolit NQ 1Bp837204557601,22110-0,12-0.4>2800
Neolit NQ 1Cp6463042014501,15125-0,08-0.4>3500
Neolit NQ 1Dp736704459201,22110-0,08-0.4>3000

1) Description based on DIN 17410/IEC 60404-8-1
2) The maximum possible operating temperature depends on the dimensioning of the system.
i = (injection) injected, p = (pressed) pressed, hardferrit 11/22 p and neolit sp 445 = anisotrop