Conditions for Bending of Thin Metal Sheet by Thermal Strain in Electrical Discharge Machining

AbstractThis paper deals with the conditions for bending of sheet metals by electrical discharge machining (EDM). The thermal strain caused by the tensile stress after EDM was used to bend a sheet metal. Plate and wedged electrode were used to bend the strips simply, and a pipe was used to form a convex shape. The negative electrode polarity was preferable to reduce the removal rate. The warp of the strip in the lateral direction disturbed the bending performance. The incremental forming by shifting the discharge position was also tried to avoid the influence of the warp