To obtain mould cavity using electroforming is a new technology to make mould cavity.

<1> Electroforming principle：
We are very familiar with electroplating: Using electroplating, we can deposit metal or plastic materials with good anti-corrosion performance such as nickel, chromium, zinc, copper etc. onto the surface of another electric conductive part. For electroforming of plastic mould: Put a master mould with high dimension precision matched with mould cavity into coating batch as cathode, then put metal to be electroplated as anode into the coating bath, then connect with DC current, then the metal will turn into metallic ions into the electrolyte then deposit on to the master mould, after certain period of time, master mould surface will be applies with a metallic layer of certain thickness which is called galvanized layer. According to different electroplating materials, there are two electroplating methods: Iron-electroplating, Copper-electroplating, Nickel-electroplating. And Nickel-electroplating is the most widely used methods because it has higher mechanical strength and higher hardness with lower surface roughness. However it requires long electroplating time and higher cost. Copper-electroplating provides high speed and low price, but its mechanical property is relatively low, and shows a lower wear prevention performance than that of Nickel.
<2> Characteristics of electroforming
Electroforming is a kind of forming methods greatly different from common forming method by mechanical cutting. Its main characteristics are as follows:
1) Electroformed part has high degree matching with master mould. And the electroformed part can meet requirements as long as the master mould is manufacture precisely. Its surface roughness Ra can reach 0.1μm.
2）Since electroforming adopts depositing method in forming, thus it can achieve good effect no matter how complicated structure is of the part. Electroforming can also be used to form cavities which is difficult or even impossible to form by mechanical machining.
3) Nickel-electroplating can provide high mechanical strength which can be put into use directly without any heat treatment.
4）Fabrication of master mould is very simple. And it is not limited to metallic materials, non-metallic material can also be used for electroplating after certain treatment. Sometimes product parts can even be used directly as the master die. <3> Disadvantages of electro deposited mould：
Fabrication period of electroformed parts, for example, Nickel-electroplating part requires several days, and high-precision parts such as navigation keys of mobile phone requires 10-15 days. And it is difficult to get uniform thickness of deposited layer; Electroformed part has large internal stress which requires appropriate heat treatment. The price of electroformed part is high, e.g. side keys or navigation keys of mobile phone cost 800-1200 yuan RMB individually. Electroformed plants in Shenzhen are mostly of small scale, fabrication precision of which can not reach satisfied effect.