Microelectricaldischarge

Microelectricaldischarge is a micrometer-scale electrical discharge machining technique used to fabricate fine, complex features in conductive materials. It relies on controlled spark erosion between a shaped tool electrode and a workpiece immersed in a dielectric fluid. A short high-voltage pulse creates a plasma channel that transfers energy to the workpiece, causing localized melting and vaporization. Repeated pulses remove material and form the desired geometry. The process is non-contact and imposes minimal mechanical stress on the part.

Microelectricaldischarge includes micro-EDM milling, drilling, and finishing operations, enabling micro-scale holes, slots, and grooves with high accuracy. Tool electrodes are typically made of copper, tungsten, or composites, and electrode wear directly influences surface quality and dimensional fidelity. Precision in gap control and flushing is essential for stable operation.

Materials machined are generally electrically conductive metals and alloys, such as tool steels, carbide, nickel-based alloys, and certain conductive ceramics or composites. Non-conductive materials cannot be machined by standard EDM processes unless special conductive paths are provided.

Key process parameters include peak current, pulse duration, pulse frequency, and dielectric flushing. Tight control of the spark gap and electrode feed determines resolution, surface finish, and overcut. Micro-EDM seeks nanometer-to-micrometer surface finishes and often employs specialized, high-precision controllers.

Advantages include the ability to machine hard materials without mechanical forces and to create complex micro features. Limitations are relatively slow material removal, electrode wear, possible recast layers, and the requirement for precise machinery and suitable conductivity. Applications span MEMS, micro-tools, medical implants, and micro-fluidic components.