Electrode wire for electro-discharge machining and method for manufacturing the same

A method of manufacturing an electrode wire for electro-discharge machining, the method comprising:

• preparing an intermediate wire rod, which includes a first metal, has one of phases α, α+β′, and β′ and has a first diameter, as a core wire;
• plating the core wire with a second metal;
• performing a heat treatment process to make the plated core wire representing tensile strength of about 500 N/mm2 or less and elongation percentage of 5 or more and to form a first alloy layer having a phase β′ in at least a boundary region between the core wire and the second metal due to mutual diffusion between the core wire and the second metal and to form a second alloy layer having a phase γ and/or a phase ε on an outer portion of the first alloy layer through diffusion of the first metal to the second metal;
• and
• forming a grain including at least a core wire material and a second alloy material on a surface of the electrode wire for electro-discharge machining by erupting the core wire material through a crack appearing on the second alloy layer when performing a fine wire process of making the electrode wire for electro-discharge machining which includes the first alloy layer, the second alloy layer, and the core wire and has a second diameter.

An electrode wire for electro-discharge machining, the electrode wire comprising:

• a core wire including a first metal and having one of phases α, α+β′, and β′;
• and
• an alloy layer formed due to mutual diffusion between the core wire and a second metal plated on an outer surface of the core wire and having one selected from among phases β′, γ, and ε,
• wherein the electrode wire for the electro-discharge machining comprising at least the core wire and the alloy layer is provided on a surface thereof with a crack, a core wire material is erupted through the crack formed in the alloy layer to form a plurality of grains, and the grain including at least the core wire material and an alloy material is distributed onto the surface of the electrode wire for electro-discharge machining.