Applying Foil Queue Microelectrode with Tapered Structure in Micro-EDM to Eliminate the Step Effect on the 3D...

Area of Science:

• Manufacturing Engineering
• Materials Science
• Surface Metrology

Background:

• Micro electrical discharge machining (micro-EDM) enables the fabrication of complex 3D microstructures by stacking processed results from foil queue microelectrodes (FQ-microelectrodes).
• A significant challenge in this process is the 'step effect' on the surface of 3D microstructures, which degrades surface quality and dimensional accuracy.

Purpose of the Study:

• To address the step effect in 3D microstructures fabricated by micro-EDM using FQ-microelectrodes.
• To investigate the efficacy of tapered FQ-microelectrodes in mitigating or eliminating the step effect.
• To analyze the influence of taper angle and the number of FQ-microelectrodes on surface quality and shape accuracy.

Main Methods:

• Fabrication of tapered FQ-microelectrodes from 300 μm copper foil using a low-speed wire electrical discharge machine.
• Systematic investigation of the effects of varying taper angles and the number of FQ-microelectrodes on the resulting 3D microstructures.
• Micro-EDM experiments conducted using optimized parameters (120 V, 1 μs pulse width, 10 μs pulse interval).

Main Results:

• Tapered FQ-microelectrodes effectively reduce and can essentially eliminate the step effect on 3D microstructures.
• An increase in taper angle and the number of FQ-microelectrodes leads to a less pronounced step effect.
• Optimized processing with a 10° taper angle FQ-microelectrode (40 electrodes) yielded 3D microstructures with excellent surface quality and minimal step effect.

Conclusions:

• Tapered FQ-microelectrodes are a viable solution for improving the surface quality and dimensional accuracy of 3D microstructures produced by micro-EDM.
• The proposed method offers a significant advancement in fabricating high-precision 3D microstructures, overcoming limitations of previous techniques.
• Further research can explore wider applications and optimization of taper geometries for diverse microfabrication needs.