Apparatus for electrochemically treating in particular selectively a conducting workpiece

A device is claimed for the electrochemical treatment, notably localised, of a conducting substrate. The device comprises: (a) an envelope (1) provided with an opening (4) and defining a space (5); (b) an electrode (6) arranged in this space (5) and designed to be connected to one of the terminals of an electric current source with the conducting substrate being connected to the other terminal of the electric current source; (c) an electrolyte supply pipe (10,12); and (d) an electrolyte outlet pipe (13,15). The device also incorporates a body (16) in an absorbent material which is in contact with the electrode (6) and closes the opening (4) and some means of creating a depression are provided. The absorbent material is flexible, electrically non-conducting and permeable to gas and liquids.