Electrical Discharge Machining - EDM

With the Electro-Erosion μ-machining - EDM technology, material is removed from a workpiece by current discharges between electrode and anode.

About Electrical Discharge Machining - EDM

The use of the latest, integrated μ-EDM technology allows machining with high quality and efficiency, meeting the needs of mass production scenarios, especially in the automotive industry.


The process is based on the electro-erosion principle. Material is removed from the workpiece by a series of rapidly recurring current discharges between electrode and anode, separated by a dielectric liquid and subject to an electric voltage. One of the electrodes is called the tool-electrode, or simply the “electrode”, while the other is called the anode, or “workpiece.”

In order to machine high quality micro holes the Posalux EDM machines have a tilting head with deformation by pressure that allows to control the diameter and the shape of the hole, resulting in a run-out of the electrode. The electrode turns on a decentered axis, giving two different gaps, one where sparks erode the material and another, bigger one, allowing a better flushing of eroded materials. In combination with CNC driven axis and a high-speed interface to communicate with the micro EDM generator, perfect micro holes are the result.

What we can do with Electrical Discharge Machining - EDM
Electrical Discharge Machining - EDM

Drilling of GDI shim plate for the automotive industry

The complexity of designs, uniquely tailored to each engine, adds difficulty in maintaining consistency and quality throughout the shim plate milling process.
Electrical Discharge Machining - EDM

Stephole drilling of GDI valve seats for the automotive industry

The main challenge of step- and sprayhole micro-machining of GDI valve seats in the automotive industry is achieving consistent precision and accuracy in creating the intricate, small-scale features while ensuring durability under high-pressure combustion conditions, all without compromising the valve's efficiency and functionality.
Electrical Discharge Machining - EDM

Spray hole drilling in diesel injection nozzle for the automotive industry

Advanced micromachining equipment and techniques ensure the accuracy and quality of the holes, as even small deviations in size or shape can significantly impact the performance and efficiency of the engine.

Answering your questions about Electrical Discharge Machining - EDM

To find out if Electrical Discharge Machining - EDM technology is the right fit for your application, we answer your questions on the subject. More questions about Electrical Discharge Machining - EDM? Our team of experts is there for you!

What material can be micro-machined with EDM-Technology?

The EDM Technology integrated in Posalux tools micro-machine parts made of conductive materials.


  • Hardened metal
  • Hardened steel
  • Steel

Metal alloys

  • Aluminium
  • Brass
  • Bronze
  • Non ferrous metals
  • Stainless steel


  • Bio-compatible material
  • Nitinol

What are the micromachining capabilities of EDM-Technology ?

  • Hole diameter from 80 μm in production up to 1.6 mm (0.003 to 0.06 inch)
  • Tapered hole with reverse taper up to 150 μm/mm
  • Wall thickness / hole diameter ratio up to 12
  • All shapes (square, rectangle, oblong, …)
  • All conductive material
  • Without burr and material deposit, no micro-crack
  • Flow stability: +/- 3 % Cp 1.67
  • Smooth roughness: Ra < 0.3 μm ; Rz < 1 μm
  • 6 holes application diameter 150 μm , thickness 0.8 mm :
    Erosion time : 25 s / hole

How is the electrode managed?

  • The shifting and guiding collets precisely feed the smallest electrodes available in the market, down to 35 μm. 
  • The spindle rotation goes up to 3500 rpm for shortest erosion time and optimized material ablation.
  • The erosion z-axis with parallel deformation parallelogram type removes mechanical axis resonances.

What specific devices and solutions are included in the EDM Technology?

  • Automatic loading / unloading
  • Accurate clamping devices
  • Software features
  • Technical support in defining μ-EDM parameters
  • User interface options

Posalux machines featuring Electrical Discharge Machining - EDM Technology

Electrical Discharge Machining - EDM


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