T-Axel Magnet Wires in Hall Thrusters

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A Hall-effect thruster is a type of electrical thruster in which the propellant is accelerated by an electrical field. The electric field is generated by a series of outer and inner coils.

 

Although the thrust generated by electrical engines pale in comparison to traditional chemical engines, they have advantages that make them very desirable depending on mission requirements. Ideal missions for ion engines involve long intervals where significant thrust/acceleration is not required (altitude correction in low earth orbits, transfers, fine adjustments, deep space probes).

Improving Efficiency & Reducing Weight

T-Axel offers pure copper for a conductor in our ceramic coated magnet wires. Pure copper has a resistivity of roughly 25% lower relative to nickel-plated copper wiring. The low resistivity compared to nickel-plated copper wire or pure nickel copper wire not only reduces weight without compromising performance, but it also allows for overall higher efficiency as the coils require less voltage to achieve the same performance. By cutting down weight in magnetic coils, spacecraft can be outfitted with greater payloads.

 

Cersion® comes in an extremely wide range of wire gauges ranging from 18-44. This versatility allows for applications in hall-effect thrusters of multiple sizes.

High Temperatures

Cersion® has an operating temperature of 600° C, making it ideal for operating in hall-effect thrusters. Even with such capabilities, the insulation layer is extremely thin (7 to 30 µm) on a wire that ranges from 0.05mm to 1.024mm.

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Advantages to Other Types of Wires

High-Temperature magnet wires include ceramic coated wires, Mica tape with glass fiber braided wires, and mineral-insulated cables.

 

The downside to mineral-insulated cables is the bulk, as they require a steel sheath on top of the insulating MgO. Although in standard operations, this would not be an issue, the lightweight requirements of spacecraft make mineral-insulated cables less than ideal.

 

Mica tape and glass fiber braided wires, although lighter than mineral-insulated cables, has a lower operating lifetime. Furthermore, mica wires do not offer small wire gauges due to technical difficulty. Larger wires mean fewer turns and more current to achieve the same field strength, meaning more weight. The lower operating lifetime would also be a detriment to the hall-effect thruster, an engine designed with long periods of operation due to low thrust.

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Ceramic coated wires present themselves as the ideal candidate - lightweight, long operating lifetimes, a wide range of gauges - with the one drawback that most manufacturers do not offer pure copper due to manufacturing difficulty. However, T-Axel offers pure copper as a conductor, overcoming this difficulty.