Additive manufacturing of functional electromechanical systems has long promised new design freedom—but until recently, practical limitations in materials, processing compatibility, and reliability have constrained what could truly be built. A recently published study from Georgia Tech demonstrates how these barriers are beginning to fall, showcasing a fully additively manufactured, multilayer radial flux electric motor stator enabled in part by silver nanoparticle conductive inks from NovaCentrix.
From NovaCentrix’s perspective as a materials manufacturer, this work is an important example of how conductive inks are evolving from “printed traces” into load-bearing, high-power functional elements that enable entirely new classes of devices.
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Fully Additively Manufactured Multilayer Stator for Radial Flux Electric Motors
Why This Work Matters
Historically, most additively manufactured electric motors have been limited to planar or axial-flux geometries, primarily because conventional three-axis printing constrains conductive features to stacked 2D layers. This research overcomes that limitation by combining:
- Direct Ink Writing (DIW) of conductive silver nanoparticle inks
- Fused Filament Fabrication (FFF) of structural insulation
- A custom four-axis (rotary) additive manufacturing platform
The result is the first reported fully additively manufactured cylindrical radial flux stator, a geometry that more closely resembles conventional electric motors but is produced entirely through digital manufacturing.
For the printed electronics ecosystem, this is a critical milestone: it shows that additive manufacturing can move beyond demonstrations toward electrically, thermally, and mechanically functional machines.
Conductive Ink as a System-Level Enabler
A central challenge in printing high-power electromagnetic devices is the thermal and rheological compatibility between conductive materials and structural polymers. In this work, the researchers selected NovaCentrix HPS-FG77 silver nanoparticle ink, citing several key attributes that are increasingly important in advanced additive systems:
- High viscosity (~5000 cP) to prevent slumping, pooling, or trace distortion on vertical and curved surfaces
- Low sintering temperatures (120–225 °C) compatible with engineering thermoplastics
- Stable deposition for multilayer printing, including interlayer vias
These properties allowed the ink to be deposited directly onto a nylon–fiberglass composite substrate, forming five-layer coils capable of supporting currents above 5 A without catastrophic failure. Importantly, the sintering window remained below the heat deflection temperature of the printed insulation, enabling true multimaterial integration rather than post-assembly.
From a materials standpoint, this highlights a broader trend: ink performance must now be evaluated at the system level, not just by bulk conductivity or sheet resistance.
Multilayer Printing Meets Real-World Operation
Beyond fabrication, the study places strong emphasis on characterization and application relevance—an area where printed electronics often fall short.
Key demonstrated capabilities include:
- Continuous operation at up to 20.7 W input power
- Operating temperatures up to 150 °C
- Measured torque output of 0.51 N·mm/A
- Functional use case: drilling through foam using a fully printed motor
While the reported efficiency (~1%) is lower than traditional motors, this is consistent with the current state of printed electromagnetic devices and reflects known tradeoffs such as air gaps, trace resistivity, and coil density. More importantly, the work shows that printed conductive inks can survive real electrical, thermal, and mechanical loads—a critical requirement for future adoption.
Implications for Printed Electronics and Additive Manufacturing
From NovaCentrix’s perspective, this work reinforces several important directions for the industry:
- Conductive inks are becoming structural elements — Printed conductors are no longer just signal paths—they are coils, heaters, and power-handling components.
- Low-temperature sintering is a gateway technology — Compatibility with engineering polymers unlocks fully integrated, print-in-place systems.
- Multi-axis printing expands design space dramatically — As hardware evolves, materials must be ready to perform on curved, rotating, and nonplanar surfaces.
- Application-driven research accelerates adoption — Demonstrations like drilling—even in soft materials—move printed electronics closer to real products.
Looking Ahead
As additive manufacturing platforms mature and printing resolution improves, many of the current limitations identified in this work—such as air gaps, coil density, and efficiency—can be addressed. From the materials side, continued innovation in conductive ink formulations, sintering strategies, and reliability under cyclic loading will be essential.
This research represents exactly the type of collaboration needed to move printed electronics forward: materials scientists, machine builders, and system designers working together to redefine what can be manufactured.
At NovaCentrix, we are excited to see our conductive inks enabling this next generation of fully additively manufactured electromechanical systems—and we look forward to supporting the continued evolution of printed power electronics, motors, and actuators.