| Electroforming, which possesses the merit of high manufacturing precision, is a manufacture technology that is based on principle of cathodic metal deposit. But it is impossible for the traditional electroforming to be widely used due to the long processing time, the poor metal distribution and some default easily emerging in deposition layer.In this paper, a new electroforming technique, numerical control jet electroforming, was proposed. The theoretic and experimental research on the new technique was carried out.Some important conclusions are presented with a great deal of foundational experiments based on theory of electrochemistry and growth method of electro-deposit.1) Results show that limiting current density of electroforming will be improved from 10~20A/dm2 to 390A/dm2 due to high mass transfer velocity and small diffusion layer thickness.2) Locality of electroforming is determined by electric field distribution and strength. It's closely relevant with voltage. The more voltage is, the higher electric field strength and distribution area. Other parameters of electroforming have an indirect influence on locality through strength and area of electric field.3) Good surface quality can be obtained by selecting optional current density and improving scanning velocity and jet flux.Initial experimental study is done about electroforming process and fluid model is set up. Electric field distribution is found to be nearly normal. When jet height is less than jet diameter, electric field strength will be decreased and locality will be improved.Finally, some problems faced by electroforming recently are further researched, included dendrite growth, online-controlling, crystal growth like pyramid. Side-sweeping transformation process is put forward too.
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