摘要 |
An apparatus for forming a generally planar metal plate into a dish with a three-dimensional pattern is provided. The apparatus comprises a mold having a forming surface with a contour corresponding to said three-dimensional pattern, and having edges corresponding to boundaries of the dish, which edges are defined by side walls essentially perpendicular to the forming plane; a forming device comprising a fluid basin and pairs of electric discharge members within the fluid and having an opening facing the mold to allow transmission of a pressure wave from the fluid to the metal plate; and an electric discharge circuitry for discharging a short and intense electric current through the pairs of electric discharge members generating an electric spark or breakdown within the fluid to yield formation of plasma, vapor or both. |