For more than a century, laminated electrical steel has been the backbone of electric motor design. It’s familiar, reliable, and has powered everything from industrial machines to today’s EV traction motors, robotics actuators, and aerospace systems. But here’s the uncomfortable question: is electrical steel limiting the future of motor innovation?
When Nikola Tesla imagined the possibilities of electrification, he also believed that iron powder materials would someday enable motor designs far beyond what stacked laminations could ever achieve. He saw that magnetic materials would need to evolve for engineers to fully unlock geometry, efficiency, and performance freedom. More than a hundred years later, with soft magnetic composites (SMCs), we may finally be standing at that inflection point.
The Hidden Ceiling of Electrical Steel
Most engineers don’t think twice about designing with laminations — it’s the way things have always been done. But this default comes with tradeoffs that often feel invisible because we’ve lived with them so long.
- 2D design constraints: Laminations force motors into flat, radial flux geometries. This limits innovation to designs that can fit within the stamp-and-stack model rather than creating the best electromagnetic topology for the application.
- Loss mechanisms: As switching frequencies climb in high-speed motors, EV drives, and robotics, lamination losses become harder to engineer around. Cooling systems and coatings become band-aids rather than solutions.
- Supply chain risks: The global electrical steel supply chain is tangled, vulnerable to geopolitical pressures, and increasingly unsustainable.
The result? Designs that are shaped more by material limitations than engineering imagination.
Axial Flux and the Geometry Question
One of the clearest examples of these limits comes in the push toward axial flux motors, yokeless axial flux machines, and trapezoidal radial flux designs. Their compact form factors and power density advantages make them a natural fit for electric vehicles, humanoid robotics, and aerospace propulsion.
Yet, building them with laminations feels like trying to sculpt a sphere out of bricks. The topology demands curved, 3D magnetic flux paths—something electrical steel was never meant to do. The frustration many engineers face in trying to adapt laminations to axial flux isn’t a failure of their ingenuity. It’s a signal that the material is holding them back.
Soft Magnetic Composites: Tesla’s Hint Realized
This is where SMCs come into play. By compacting insulated iron powders into complex 3D forms, SMCs make it possible to design motors the way engineers wish they could—with freedom of shape, optimized flux paths, reduced core loss, and simplified manufacturing.
Tesla didn’t live to see it, but his intuition about iron powders was right: they offer a path to three-dimensional motor geometries that laminations can’t support. Imagine:
- Stators shaped to guide flux in natural curves rather than bent to fit laminated constraints
- Motors optimized for high frequency operation in robotics and electrified aerospace
- Compact axial flux machines that deliver higher torque density without multiplying parts
- Sustainable motor manufacturing with less scrap and easier recycling
This isn’t science fiction anymore. It’s a call for engineers to stop asking, How do I work within the lamination box? and start asking, What does the right magnetic geometry look like if the box doesn’t exist?
Time for Engineers to Push the Boundaries
The industry’s reliance on electrical steel has bred a kind of quiet complacency. But humanoid robotics, EV drivetrains, and electrified aerospace won’t be defined by incrementalism. They’ll be defined by breakthroughs in power density, motor efficiency, and manufacturability.
The tools to reach those breakthroughs exist today. SMCs and new motor topologies like axial flux and yokeless axial flux aren’t silver bullets. They require new design thinking, new testing, and a willingness to leave behind the comfort of the way it’s always been done. But isn’t that exactly what engineers are here to do—break the ceiling rather than just build taller walls beneath it?
The Provocation
Electrical steel built the motors that got us here. But it may not build the ones that take us where we need to go.
So the real question is, Will you keep designing within the constraints of yesterday’s electrical steel, or will you push yourself—and the industry—to design with the possibilities of tomorrow’s materials like SMCs?
