Micromanufacturing Process of Complex 3D FeCo Core Microwindings for Magnetic Flux Modulation in Micromotors

Area of Science:

• Materials Science
• Electrical Engineering
• Mechanical Engineering

Background:

• High-torque axial-flux Vernier micromotors require advanced flux modulation.
• Conventional micromanufacturing methods are insufficient for complex 3D micro-components.

Purpose of the Study:

• To design, fabricate, and characterize a 3D FeCo-based flux-modulator microwinding.
• To enable the integration of this component into high-torque micromotors.
• To establish a viable micromanufacturing workflow for complex 3D microwindings.

Main Methods:

• Femtosecond laser-machining for fabricating 3D FeCo parts (250 μm OD, 355 μm height).
• Development of a magnetic clamping fixture for multilayer microwinding with 20 μm copper wire.
• Geometric and magnetic characterization to validate simulation models.

Main Results:

• Successful fabrication of a 17-turn inductor with a 60.6% fill factor, the highest reported for this scale.
• Demonstration of preserved surfaces and minimal heat-affected zones using femtosecond laser machining.
• Validation of the simulation model through geometric and magnetic characterization, showing accurate field distribution.

Conclusions:

• A viable micromanufacturing workflow for complex 3D FeCo microwindings has been established.
• The developed flux-modulator microwinding supports the advancement of next-generation high-performance MEMS micromotors.
• This work paves the way for novel micro-motor designs with enhanced torque capabilities.