Wire and sinker electrical discharge machining (EDM) can perform high-precision micromachining of complex components in difficult-to-machine materials like hardened steels, high nickel alloys and carbide.
EDM offers highly accurate and repeatable capabilities while also providing superior surface finishes. This makes it perfect for high-precision applications including injection molds, stamping dies, medical implants, medical devices and aerospace components, just to name a few.
Electrode Design for Micromachining
For micro-scale features, EDM has the capability to use very small electrodes, with features that are sometimes smaller than 0.1mm / .004 in.
Electrodes are often made from graphite, copper or tungsten, which withstand repeated sparking and provide precision machining capabilities.
Control over Micromachining
High-frequency pulses and very low discharge energy levels are used to control the amount of material removed, achieving the fine, delicate machining necessary for micro-scale applications.
Precise CNC control and advanced software allow the EDM process to follow complex paths, resulting in intricate micro-features with tight tolerances.
Finishing and Precision
Due to the minimal force involved, EDM can create sharp edges, small holes, fine grooves and other intricate details without causing deformation.
Benefits of Wire EDM in Micromachining
High precision and accuracy: Wire EDM offers exceptional precision, which is crucial for machining applications where even minor deviations can be problematic. The process can achieve tolerances as tight as ±0.001 mm (1 micron) making it ideal for producing intricate components.
Ability to machine hard materials: Wire EDM is effective on hard materials such as carbide, titanium and hardened steel, which are challenging to machine with traditional cutting tools. This ability expands material options for micro-machined parts, especially in demanding applications for aerospace components and medical devices.
No mechanical stress on workpiece: As a non-contact process, wire EDM does not exert physical pressure on the workpiece, avoiding deformation and minimizing residual stresses. This is critical for delicate, thin or very small parts that could be damaged by conventional machining.
Ability to machine complex geometries: Wire EDM enables the creation of complex geometries, including sharp internal corners, intricate contours and precise angles, which are difficult or impossible to achieve with traditional cutting tools. This makes it ideal for micro-features required in mold making, precision tooling and electronics.
Ability to achieve fine surface finishes: Wire EDM achieves excellent surface finishes (up to Ra 0.1 µm) without additional finishing operations. This high-quality finish is essential in micromachining, where even small surface imperfections can affect component performance or assembly fit.
Minimal Heat-Affected Zone (HAZ): Wire EDM generates minimal heat, reducing the HAZ around the cut area. This is crucial in micromachining, where high temperatures could alter material properties or cause micro-cracks that compromise component integrity.
High reproducibility and repeatability: Wire EDM offers highly reproducible results, making it well-suited for high-precision production runs in micromachining. This ensures consistency across multiple parts, critical in industries like medical, automotive and electronics.
Low wire consumption: With the latest in EDM generator technology, the spark is controlled precisely during discharge. This reduces wear on the wire, keeping operating costs low.
Benefits of Sinker EDM in Micromachining
High precision and accuracy: Sinker EDM allows for high precision and complex geometries. It can achieve tight tolerances (down to a few microns) and sharp internal corners, which are challenging with conventional machining methods.
Ability to machine complex shapes and fine details: Sinker EDM can produce fine details and complex shapes, including deep cavities, intricate contours and thin walls, without the need for additional tooling. It is often used for creating molds, dies and parts with delicate features required in the medical, electronics and aerospace industries.
No mechanical stress on workpiece: As a non-contact process, sinker EDM does not exert physical force on the workpiece. This minimizes mechanical stress and makes it ideal for machining fragile, small parts that could otherwise deform. Non-contact machining also allows for handling materials that are difficult to machine using traditional methods, such as hard metals and superalloys.
High surface finish quality: Sinker EDM can produce a smooth surface finish with minimal post-processing. Finishing passes in EDM improve the surface quality to achieve mirror-like finishes, which are often required in micromachining.
Material flexibility: Sinker EDM can machine any conductive material, regardless of hardness, such as titanium, tungsten and carbide. This flexibility is advantageous when working with hard-to-machine metals.
Reduced tool wear: Since there is no direct contact between the tool and workpiece, tool wear is minimized. This is important in micromachining, where maintaining tool shape and accuracy is crucial for small-scale precision.
Ability to produce micro-features and small-diameter holes: Sinker EDM excels at producing micro-features, including small-diameter holes with high aspect ratios that conventional machining struggles to achieve. This capability is essential in applications such as medical device manufacturing, micro-electronics and precision molds.
Automated and repeatable: Sinker EDM can be automated, allowing for consistent, repeatable results in batch production, which is valuable for small, precise parts.