MANUFACTURING METHOD OF ZINC COATED ELECTRODE WIRE FOR ELECTRICAL DISCHARGE MACHINE USING HOT DIP GALVANIZING

摘要

PURPOSE: A manufacturing method of zinc coated electrode wire for electrical discharge machine using hot dip galvanizing is provided to uniformly coat molten zinc on the outer surface of the electrode wire for the electrical discharge machine by sequentially passing a work through a series of processing steps. CONSTITUTION: The manufacturing method comprises a work surface forming step of forming the outer surface of a wire rod shaped work(1) in the process of drawing the work through dies; a pre-coating step(20) of coating zinc on the outer surface of the formed work by passing the work passing through the work surface forming step into a molten zinc tank; a main coating step(30) of performing plating by staying the work passing through the pre-coating step in the molten zinc tank, and moving the work to the outside of the molten zinc tank so that the work passes through sizing dies preheated to 400 deg.C to obtain a certain coating thickness; a surface forming step(40) passing the work passing through the main coating step through the inside of a heated pipe so that the surface of the work reaches a certain temperature, and passing the heated work through dies having diameter that is about 5 to 10 μm less than diameter of the wire so that zinc(3) adhered to the surface of the work is flatly formed again uniformly on the circumference of the work; a homogenization heat treatment step(50) of evenly heating the work by circulating hot blast around the work after putting the work passing through the surface forming step into a sealed space; and a drawing step(60) of passing the work passing through the homogenization heat treatment step through dies(5), thereby smoothly forming the surface of the work to obtain thickness of the work corresponding to cross sectional area of 0.3 to 3 mm¬2 so that the work is drawn to a size of 4 to 80 times.