The Use of Thermoplastic Composites in Electric Motors
This page offers a brief overview of the application of thermoplastic composites in rotor and stator sleeves. For more information on the types of electric motor, design considerations and scaling for high-volume production, download the complete document.
Why Material Selection Matters in Electric Motor Design
As industries transition toward high-efficiency, high-voltage electric motors, material selection for key components is becoming a decisive factor in performance. Rotor and stator sleeves are critical elements in modern motor design, influencing mechanical stability, efficiency, and thermal management. While traditional materials like metals and thermoset composites have dominated the market, thermoplastic composites offer new advantages that make them an ideal alternative for next-generation electric motors.
How Rotor & Stator Sleeves Benefit from Thermoplastic Composites
Rotor Sleeves: Strength, Speed, and Stability
Rotors in electric motors operate at high speeds, subjecting their components to extreme centrifugal forces and thermal stresses. Rotor sleeves play an essential role in ensuring:
• Magnet Retention – Preventing magnet displacement in surface-mounted and embedded magnet configurations.
• Structural reinforcement – Enables thinner steel bridges and reduces electromagnetic losses.
• Dimensional Stability – Maintaining a precise air gap between the rotor and stator, which directly impacts motor efficiency.
Challenges of Current Materials:
• Metals add weight and create eddy current losses.
• Thermoset composites require complex manufacturing processes and are difficult to recycle.
✅ Why Thermoplastics Composites?
• Lightweight and high-strength, reducing rotor inertia while maintaining structural integrity.
• Reduce eddy current losses, improving motor efficiency compared to metal sleeves.
• Thin-walled design, allowing for compact and high-speed rotor configurations.
• Highly durable, resisting fatigue and stress cracking even at extreme rotational speeds.
Stator Sleeves: Improved Thermal Management & Efficiency
Thermal regulation is a key challenge in high-performance electric motors, especially in EVs, industrial applications, and aerospace systems. Stator sleeves help optimize heat dissipation while ensuring the rotor remains dry, preventing unnecessary fluid friction.
In actively cooled motors, a stator sleeve allows for:
• Improved thermal efficiency, by sealing the cooling system from the rotor.
• Better structural integrity, reinforcing the stator without compromising its electromagnetic properties.
• Customizable insulation properties, depending on the fiber/polymer combination used.
Challenges of Current Materials:
• Metals, while effective in heat dissipation, are prone to corrosion and require additional insulation layers to prevent electrical interference.
• Thermoset composites, are more complex to manufacture to meet requirements.
✅ Why Thermoplastics Composites?
• Superior heat resistance, ensuring long-term stability at high operating temperatures.
• Customizable thermal and electrical properties, depending on fiber layup and polymer choice.
• High-precision manufacturing, allowing for tight tolerances in stator cooling systems.
• No need for additional surface treatments, reducing overall processing steps.
The Seven Key Advantages of Thermoplastic Composite Sleeves
1. Lightweight & Strong – Enables high-speed motor designs without adding unnecessary mass.
2. Better Electrical Insulation – Resistant against eddy current losses, increasing motor efficiency.
3. Superior Thermal Stability – Ensures dimensional accuracy and structural integrity under extreme conditions.
4. Thinner Sleeves – Achieves necessary mechanical properties with reduced material usage.
5. Automated & Scalable Manufacturing – Produced with laser-assisted tape winding (LATW) for consistent quality.
6. Room Temperature Processing – Direct winding onto permanent magnets without the risk of demagnetization.
7. Environmentally friendly & recyclable – Fully recyclable, lower carbon footprint and free from harsh chemicals.
Download the Full White Paper
This white paper is designed for electric motor engineers and thermoplastic composite specialists, providing valuable insights into:
• Material comparisons: Metals, thermosets, and thermoplastics in e-motor applications
• Key design considerations: Wall thickness, fiber orientation, tape tension, and assembly methods
• Manufacturing scalability: How automation makes thermoplastic composites a viable industry solution