Blunting and deburring

The technology of electrolyte-plasma polishing allows not only to polish a workpiece surface, but also to make deburring. Metal polishing duration is 2–5 minutes, that of deburring is just 5–20 seconds. By electrolyte-plasma polishing, pulsed electrical discharges are running on all work surface and are most active while running protuberances. Joint exposure of a workpiece to chemically active medium and electrical discharges can lead to simultaneous effect of polishing, deburring and blunting.

Fig. 1. Electric motor commutator a — before processing: burrs and sharp edges are seen in slots; b — after processing for 5 minutes: burrs are removed, sharp edges are flattened

Often blunting and polishing of a workpiece are carried out jointly (see fig.1), however, the technology makes it possible work out special electrolytes for deburring and depot fat removal without polishing. For instance, aluminum and its alloys, titan and steel Р6В5 were tested.

Jet processing is advanced direction leading to processing optimization and energy intensity reduction. The technology allows to remove local burrs and saves time and resources. Electrolyte jet is turned under pressure through a nozzle on a cut. Burning between an electrolyte jet and a blank, discharge plasma have an electrochemical effect on a work material. The electrolyte function reduces mainly to current supply, processing products removal and control of exposure area. It is stated that removal of burrs with a height of up to 16.10-7m by the use of energized electrolyte jet can provide deburring rate up to 0,01 m/min. .

Among the applications of this method is the use of electrolyte flow directed in products with deep cavities. The electrolyte is supplied with a hose to a long-length workpiece, fixes above the electrolyte level in operating cell. The product itself is not in contact with the electrolyte and has a positive polarity. The additional metal electrode is located within a product's cavity, and the electric circuit is closed by the motion of the electrolyte through the cavity and holes. At the same time, the electrolyte flow within the cavity performs the function of cooling the cathode and delivers a reagent into the processing zone. This type of jet is used for removal of burrs, formed after drilling in long-length cavities, e.g. in aluminum or steel injection ramps of a motor engine.

The given method can find its own niche in a production string of metal blanks' processing in up-to-date processes of manual and automated cleaning of parts' edges and that of deburring.