Electrical processing method instead of using cutting tool processing, the electrode will be between the tool and the workpiece through current, use electricity to the workpieces into required shape processing method called electrical processing method can be broadly divided into two kinds of chemical method and physical method.
The shape of the electrical discharge machining with discharge phenomenon as figure 19 as in the processing liquid make between workpiece and electrode generate continuous discharge and electrode by a high fever and discharge pressure processing, again a little removed workpiece surface trace and made into the shape of the processing method. It has following numerous features:
Can be difficult to cut, can not be processed in the processing of super hard alloy and other materials for the complex shape of the processing;
Because the electrode and the workpiece can not be contact (interval 0.02 - 0.2mm), so it can be carried out in the cutting process due to the impact of the cutting force and the deformation of the shape of the part of the processing and the processing of soft metal;
After the quenching parts, the machining of the parts can be more accurate;
The unmanned operation and complex shape parts processing requirements can be automatically processed for accuracy;
The fine processing and easily machined surface roughness as well.
Used in electrical discharge machining electrode material, copper, graphite, tungsten copper, silver, tungsten, steel and so on. Electrode scheduling of automatic processing transfer. In addition, the electrode due to the discharge loss. Electrode processing method from the shape, quantity consider again from the cutting, casting, electroforming, flaming spraying selected. Working fluid from the machining efficiency, the general use of kerosene, but also useful for water and emulsified oil.
The feeding mechanism is the gap between the work piece and the electrode, which is caused by the thread or the oil pressure, so the servo feed mechanism is adopted.
Because the power is generally easy to set the processing conditions, so the use of efficient processing of the transistor vibration mode.
Wire cut EDM machine is in the workpiece and electrode line (mainly brass wire 0.02 - 0.2 mm), produced 1000 one ten thousandth of seconds to one hundred thousandth of seconds of continuous pulse discharge, thus melting workpiece will blow it into the required shape, and a non-contact processing machine of this shape. Processing method is loaded workpiece worktable of X, Y direction at the same time, the two axis control, to continuously feed copper to cutting.
Now in order to corresponding automatization, after starting hole inserting wires, processing if there is broken wires, but also with automatic wire feeding device of the aircraft, it can automatically remove broken wires and cables with new and start working.
Electrochemical machining and electroplating on the contrary, it is by electrolytic removal method for processing surface of the wires. As shown in Figure 20. In the wire and electrode between the high-voltage electrolyte flow and make both energized, the workpiece will be closest to the electrode from the start bit by bit is processed into the same and electrode shape. Electrochemical machining and spark machining to to carry on the processing of difficult cutting material surface with complex shape. Compared with EDM. It has the following characteristics:
Because there is no high fever, so it will not have a bad effect because of heat;
Machining speed is much faster than electric discharge machining;
Without loss of a point electrode
Although there are so many advantages, but on the other hand, it also has its disadvantages:
Precision no EDM machining;
It is difficult to make the processing fluid equal to the flow;
The processing fluid is easy to corrosion metal, and so on.
The electrodes are made of copper, brass, graphite, steel and so on. It is mainly used for salt water and soda solution.
Electrolytic grinding it is a and mechanical grinding machining to remove generated by electrolytic grinding workpiece surface membrane of composite processing method. Cast iron used in pole, copper, brass, lead the friction law, using sand method. Electrolyte is harmless to the human body but can easily become matter, mainly uses is with corrosion resistance of nitrite soda but some of its main features are:
The most suitable for soft materials and super hard alloy and so on the processing of heat sensitive materials
Second, even with a soft material processing does not produce burr
The surface roughness is also very good because of the deterioration of the machining process.
The electrolytic grinding efficiency is better compared to dozens of times