Research on bipolar pulse current electroforming in precision molds and dies

Electroforming is a specialised electroplating process for the manufacture of precision metal parts and mold tooling. Because it can simplify technical process and shorten molding cycles, electroforming is also a rapid manufacturing technology. Compared with direct and unipolar pulse current, bipolar pulse current in electroforming can obtain fine structure and grain size as well as surface leveling, resulting in better precision and surface finish. In this paper, bipolar pulse current electroforming is introduced. The influencing parameters such as electrolyte parameter, additives, current density, pH, temperature, and pulse parameters have been studied by experiments. Experiments on nickel electroforming in molds and dies have been done. The results indicated that bipolar pulse current electroforming could improve the quality and precision further, while reducing internal stress.