It comes standard on Makino's S-series machines, which sell at a slight premium to standard EDMs. Adoption of HQSF in the rest of Asia, meanwhile, is minimal. This is attributed to inexpensive manual labor as well as operator insecurity. The only additional operational task is the monitoring of dielectric performance in the additive. The additive can also be filtered to allow the HQSF-equipped EDM machine to be used conventionally.
Additive powders act as a bridge between the electrode and workpiece.
In effect, they diffuse a large spark emanating from the electrode into smaller sparks impinging on the workpiece. Attaining a fine surface finish requires the electrode to be in close proximity with the workpiece. In large graphite electrodes, grain size limits how close the electrode can get to the workpiece. But the powders' bridging effect enables a wider spark gap. The principle of using powder additives such as silicon in the dielectric fluid to enhance surface finish and accelerate machining has been around for more than 30 years, but it hasn't taken off in the tooling industry.