Machining of low electrical conductive materials by wire electrical discharge machining (WEDM)

This theoretical and experimental study of WEDM of low conductive materials demonstrates that total electrical resistance between the workpiece and wire electrode vary during machining depending upon the clamping position. This change in resistance causes a change in material removal rate (MRR) and average surface roughness that leads to poor quality of products. A technique developed in this work minimizes the change in resistance offered by the workpiece material. A conductive silver coating is applied over the workpiece surface. Due to silver coating, the drop voltage in workpiece material is reduced; thereby decreasing energy loss in workpiece material. It was also observed that conductive silver coating not only minimizes the variation in resistance but also it increases the productivity of the process.