Alloy powder cores are the preferred magnetic material for power inductors, PFC chokes and output filters where stable inductance under DC bias is critical. But with three main families—Sendust (Fe-Si-Al), Molypermalloy (MPP, Ni-Fe-Mo) and High Flux (Ni-Fe)—choosing the right one can be confusing.
This guide compares the three powder core families, their properties, cost and ideal applications, to help you select the right material for your inductor design.
Shaanxi SiRui Technology Co., Ltd. manufactures powder cores and wound inductors in Sendust, Kool Mμ and High Flux materials. Contact: sales@sirui-tech.com | Web: www.sirui-tech.com
1. Sendust (Fe-Si-Al / Kool Mμ)
Iron-silicon-aluminum alloy. Bsat ~1.0 T. Permeability 26–125. Moderate core loss. Lowest cost among powder cores. Best for PFC inductors, output filters and general power inductors.
2. MPP (Molypermalloy, Ni-Fe-Mo)
Nickel-iron-molybdenum alloy. Bsat ~0.75 T. Permeability 14–550. Lowest core loss of all powder cores. Highest cost. Best for high-Q resonant circuits, precision filters and audio applications.
3. High Flux (Ni-Fe)
Nickel-iron alloy. Bsat ~1.5 T (highest of the three). Permeability 14–200. Medium-high core loss. Best for high-current inductors where small size matters (EV, server, industrial).
4. Side-by-Side Comparison
| Property | Sendust | MPP | High Flux |
|---|---|---|---|
| Composition | Fe-Si-Al | Ni-Fe-Mo | Ni-Fe |
| Bsat (T) | 1.0 | 0.75 | 1.5 |
| Core loss | Medium | Lowest | Medium-High |
| DC bias | Good | Moderate | Best |
| Cost | Lowest | Highest | Medium-High |
5. When to Choose Which
- Sendust: cost-sensitive PFC/output inductors, general power supplies
- MPP: lowest loss, high-Q filters, premium applications
- High Flux: high current, small size, EV/server power
6. Sirui-Tech Powder Core Products
- Sendust (Kool Mμ) toroids: standard PFC and output inductors
- High Flux toroids: high-current, small-size applications
- MPP cores: high-Q precision applications
- Custom wound inductors: wound to your specs
Conclusion
Sendust is the cost-effective workhorse. High Flux wins for high current and small size. MPP is the premium low-loss choice. Match the material to your DC bias, frequency and cost target.
Need powder core inductors? Contact Sirui-Tech at sales@sirui-tech.com with your inductance, peak current and frequency.