The invention relates to an electrode holder (1, 2, 14) for the multichannel electrical discharge machining in electrical discharge machines. It comprises a holding element (17), a central body (15) and an electrode mounting section (19). According to the invention, the electrode mounting section (19) includes at least two clamping sections (22) for clamping electrodes (9, 10), wherein each clamping section (22) is connected, preferably via a current feeder section (21), with an own current supplying circuit (20) leading from the periphery of the electrode holder (1, 2, 14) to the respective electrode clamping section (22). The current supply circuits (20) are electrically isolated from each other by one or more insulating elements (8, 12, 25, 26, 30). Preferably the current supplying circuits (20) are allocated in or at the central body (15) of the electrode holder (1, 2, 14).

A method of joining a first component and a second component includes providing the first component including a first surface; providing the second component including a second surface; creating a braze joint between the first and second surfaces using a sinker electrical discharge machining (EDM) device, where the first component is used as an electrode of the sinker EDM device and a voltage is generated between the first and second components such that the braze joint is created by spark erosion of at least one of the first component and the second component; and coupling the first and second components securely together along the braze joint.

An object is to provide a graphite-copper composite electrode material that is capable of reducing electrode wear to a practically usable level and to provide an electrical discharge machining electrode using the material. A graphite-copper composite electrode material includes a substrate comprising a graphite material and having pores, and copper impregnated in the pores of the substrate, the electrode material having an electrical resistivity of 2.5 m or less, preferably 1.5 m or less, more preferably 1.0 m or less. It is desirable that the substrate comprising the graphite material have an anisotropy ratio of 1.2 or less. It is desirable that an impregnation rate of the copper in the electrode material is 13% or greater. It is desirable that the substrate comprising the graphite material have a bulk density of from 1.40 Mg/m.sup.3 to 1.85 Mg/m.sup.3.