Fe16N2 in the rotor. Fe4N in the stator.
Iron and nitrogen – the fourth and second most abundant elements in the Earth's crust and atmosphere – arranged into two crystal structures that together outperform every rare-earth-based generator material on the market. This page is the technical brief.
What we're actually swapping out.
The base generator is Bill Mercer's patented split-rotor multiphase architecture – a machine that separates the rotor into segmented sections carrying the permanent-magnet flux and links them through a carbon-fiber compression sleeve. In the legacy configuration, the rotor magnets are neodymium-iron-boron (NdFeB) and the stator laminations are grain-oriented silicon steel.
Our substitution replaces two things and only two things:
- Rotor magnets: NdFeB → α''-Fe16N2.
- Stator core: laminated silicon steel → sintered γ'-Fe4N.
Everything else – the winding topology, the bearing geometry, the inverter frame, the cooling loop – carries over from the underlying patent unchanged. This is why we can move fast: the mechanical package is already engineered.
The two components. Nothing else.
Every design gain flows from the two component swaps. Fewer moving parts, fewer new tolerances, fewer supply-chain unknowns. The machine that Bill's patent describes still spins; it just doesn't need a Chinese-refined magnet to do it.
What carries over
Segmented rotor + carbon-fiber compression sleeve. Multiphase winding topology. Bearing geometry. Cooling loop. Inverter frame. Every one is unchanged from the reference architecture.
Why iron-nitride beats neodymium.
Saturation magnetization – the raw magnetic strength
Fe16N2 has a theoretical Msat of ~2.4 T, with strained-film measurements reaching 2.8–3.1 T. NdFeB tops out around 1.6 T. Higher Msat means less magnet material for the same air-gap flux – roughly 63% less by volume at equivalent generator performance.
Energy product (BH)max – useful work per unit volume
Fe16N2 is projected to hit ~143 MGOe versus NdFeB's 56 MGOe. That's a 2.5× improvement in the fundamental figure of merit for permanent-magnet generators.
Curie temperature – the failure mode under heat
Fe16N2 holds magnetization from ~361 °C through as high as 540 °C depending on preparation. NdFeB falls apart at 315 °C. Higher Curie means a safer, longer, more forgiving thermal envelope inside a running generator.
Fe4N stator – the eddy-current killer
γ'-Fe4N sintered solid has electrical resistivity up to 200× that of nanocrystalline soft-iron alloys. At 100 kHz switching frequency the core loss drops from 4,048 MW/m³ (0.35 mm laminated silicon steel) to 1,297 MW/m³ – a ~68% loss reduction without the manufacturing complexity of laminated cores.
Mechanical – the segmented rotor
A monolithic Fe-N rotor would fail from centrifugal stress around 4,750 RPM. Our design segments the rotor and wraps it in a carbon-fiber compression sleeve, which keeps every segment compressive through 12,000 RPM – well past the design point of every unit in the product ladder.
| Metric | Fe16N2 (ours) | NdFeB (legacy) |
|---|---|---|
| Msat | 2.4 T (up to 3.1 T strained) | 1.6 T |
| (BH)max | ~143 MGOe | 56 MGOe |
| Curie temperature | 361 – 540 °C | 315 °C |
| Volume at equivalent flux | -63% | 1.00× |
| Fe4N core loss @ 100 kHz | 1,297 MW/m³ | 4,048 MW/m³ |
| Feedstock supply | Iron ore + N (domestic) | Nd (~95% China) |
Iron and nitrogen. Both domestic. Both abundant.
Iron is the fourth most abundant element in the Earth's crust and the U.S. has significant proven reserves. Nitrogen is 78% of the atmosphere. Extraction is 70–90% cleaner than neodymium refining on greenhouse gases, water consumption, and chemical waste. And every stage – ore, powder, sintering, magnetization, assembly – can happen inside the United States.
We're sourcing Fe16N2 powder from Niron Magnetics (the commercial pioneer of the material) and qualifying two alternate suppliers in parallel so the supply chain isn't single-vendor at any point.
Open research threads
- Ternary alloy tuning (Co / Mo / W ratios) to push (BH)max further
- Second-source Fe16N2 powder qualification
- Fe-N electrode candidate screening for graphene & Na-ion-graphene cells
- Super-capacitor pilot cell chemistry
Filed as a provisional. Owned by Business Development LLC.
The Fe16N2 rotor + Fe4N stator substitution on the split-rotor multiphase generator is being filed as a U.S. provisional patent, joining the ROSE-001, SonicBrief, XODIAK, Okari GX, and UQCTA provisional cluster held by Bill's operating entity, Business Development LLC.
Filing establishes a priority date and unlocks the "patent pending" designation for institutional conversations, government-contract submissions, and pilot RFPs.