MPP Cores

MPP toroidal cores are manufactured from an alloy powder comprising 80% nickel, 2% molybdenum and the balance iron, utilizing distributed air gap technology. The alloy powder is produced by means of mechanical or chemical atomisation, prior to being mixed in an aqueous process with inorganic silicates and oxides so that each particle is coated with a layer to prevent electrical contact during and subsequent to the compacting process. The powder is dried and stored in a controlled atmosphere.

The compacting process produces the required shape and size of component by pressing calculated amounts of powder in a die at considerable mechanical pressures, resulting in component densities of 7-8g/cm3. Further processing, which includes heat treatment and radius forming, produces the highly controlled physical and magnetic properties this material exhibits. The toroidal cores are then painted with an epoxy resin which forms a resilient moisture- and solvent-fast finish, having excellent dielectric properties.

The result is a product offered in a range of sizes and permeabilities with a high saturation flux density (up to 0.7 tesla), high curie temperature, good thermal stability and low hysterisis and eddy current loss. It also exhibits excellent magnetic stability to DC magnetisation.

  • Typical applications include:-
    • Low and band pass filters
    • SMPS transformers
    • Loading coils
    • RFI filters

High Flux Cores

The High Flux (H grade) follows a similar manufacture and process route to the MPP grade material, except that the composition is 50% nickel and 50% iron. This variation results in a material suitable for high saturation flux density applications (up to 1.5 tesla), whilst still maintaining a considerably lower core loss than that of powdered iron. A further advantage over powdered iron is less change of permeability due to AC excitation, DC bias and temperature.

  • Typical applications include:
    • SMPS energy storage filter inductors
    • RFI suppression filters
    • Noise filter

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