What is the principle of wire EDM?

Wire EDM.

The machine belongs to the category of electrical machining, which was developed by the former Soviet Union.

When Mr. and Mrs. Lazarinko studied the phenomenon and causes of spark discharge corrosion damage to switch contacts, they found that the instantaneous high temperature of electric sparks can melt and oxidize local metals and corrode them, thus creating and inventing the EDM method. The wire cutting machine was also invented in the former Soviet Union in 1960, and China was the first country to use it for industrial production.

The principle of wire EDM: free positive ions.

and electrons accumulate in the field, soon forming a conductive channel that is ionized. At this stage, an electric current is formed between the two plates. As a result, numerous collisions between the particles form a plasma region, which soon rises to a high temperature of 8,000 to 12,000 degrees, instantly melting some material on the surface of the two conductors, and at the same time, due to the vaporization of the electrode and the dielectric liquid, a bubble is formed, and its pressure rises regularly until it is very high.

Then the current is interrupted and the temperature drops suddenly, causing the bubbles to turn inward**, and the resulting power throws the melted material out of the crater, and then the corroded material re-condenses into small spheres in the dielectric solution and is discharged by the dielectric solution. Then through the monitoring and control of NC control, the servo mechanism is executed to make this discharge phenomenon uniform and consistent.

Its basic working principle is to use a continuously moving thin metal wire (called electrode wire) as an electrode to carry out pulse spark discharge on the workpiece to abrode the metal and cut the forming.

Wire EDM Technology Principle:

Wire EDM is the processing of parts by the principle of electrical discharge of electric sparks. The workpiece is connected to the positive electrode of the pulse power supply, molybdenum wire or copper wire is used as the cutting wire, and the metal wire is connected to the negative electrode of the high-frequency pulse power supply as the tool electrode, and the spark discharge is used to cut the machined parts.

The pulsed power supply provides the processing energy, and a special wire-cut working fluid is used to remove the debris generated during the machining process. Under the action of the electric field, the surface of the cathode and anode is bombarded by the electron flow and ion flow respectively, which causes the instantaneous high-temperature heat source to form in the electrode gap to melt and vaporize the local metal.

After vaporization, the working fluid and the steam of the workpiece material expand rapidly instantaneously, and under the combined action of this thermal expansion and the stamping of the working fluid, the melted and gasified workpiece material is thrown out of the discharge channel, so as to complete a spark discharge process.

In EDM, the tool electrode and the workpiece are connected to the two poles of the pulse power supply and immersed in the working fluid, or the working fluid is charged into the discharge gap. When the gap between the two electrodes reaches a certain distance, the pulse voltage applied on the two electrodes breaks down the working fluid and produces spark discharge.

A large amount of heat energy is instantaneously concentrated in the microscopic channel of discharge, the temperature can be as high as more than 10,000 degrees Celsius, and the pressure also changes sharply, so that the local trace metal materials on the working surface are immediately melted and vaporized, and splashed into the working liquid, rapidly condensed, forming solid metal particles, which are taken away by the working liquid. At this time, a small pit trace is left on the surface of the workpiece, the discharge is stopped for a short time, and the working fluid between the two electrodes is restored to the insulating state.

Immediately after that, the next impulse voltage breaks down at another point where the two electrodes are relatively close together, resulting in a spark discharge, and the process is repeated. In this way, although the amount of metal abroded by each pulse discharge is very small, because there are thousands of pulse discharges per second, a large amount of metal can be ablated, and there is a certain productivity. Under the condition of maintaining a constant discharge gap between the tool electrode and the workpiece, the metal of the workpiece is eroded, and the tool electrode is continuously fed to the workpiece, and finally the shape corresponding to the shape of the tool electrode is processed.

Therefore, by changing the shape of the tool electrode and the relative movement between the tool electrode and the workpiece, a variety of complex profiles can be machined.

Tool electrodes are commonly used with electrocorrosion-resistant materials with good conductivity, high melting point and easy processing, such as copper, graphite, copper-tungsten alloy and molybdenum. During machining, the tool electrode also has losses, but it is less than the amount of metal removal from the workpiece, or even close to no loss.

As a discharge medium, the working fluid also plays a role in cooling and chip removal during processing. Commonly used working fluids are media with low viscosity, high flash point and stable properties, such as kerosene, deionized water and emulsion.

Summary. 1. When CNC wire cutting machine tool processing, the electrode wire is connected to the negative electrode of the pulse power supply, and the workpiece is connected to the positive electrode. 2. In daily life, it is often seen that electrical appliances produce sparks at the moment of opening and closing or disconnecting, and the high temperature generated by the sparks melts on the contacts and appears uneven spots, which is the phenomenon of electrical corrosion.

It can cause the switch to have poor contact and eventually damage, which is the harmful side of the phenomenon of electrical corrosion. 3. EDM wire cutting is referred to as "wire cutting". It uses electrode wire (molybdenum wire, tungsten molybdenum wire, etc.) as the tool electrode, under the action of pulse power supply, a spark discharge is formed between the tool electrode and the processed workpiece, and the spark channel instantly generates a large amount of heat, so that the surface of the workpiece is melted or even vaporized.

1. When CNC wire cutting machine tool processing, the electrode wire is connected to the negative electrode of the pulse power supply, and the workpiece is connected to the positive electrode. 2. In daily life, it is often seen that electrical appliances produce sparks at the moment of opening and closing or disconnecting, and the high temperature generated by the sparks melts on the contacts and appears uneven spots, which is the phenomenon of electrical corrosion. It can cause the switch to have poor contact and eventually damage, which is the harmful side of the phenomenon of electrical corrosion.

3. Wire cutting processing is referred to as "wire cutting". It is the use of electrode wire (molybdenum wire, tungsten molybdenum wire, etc.) as the tool electrode, under the action of pulse power supply, the spark discharge is formed between the tool electrode and the machining workpiece, and the spark channel instantly generates a large amount of heat, so that the surface of the piece melts or even vaporizes.

Direct copy-paste?? Cow.

Because the principle of EDM wire cutting is the same as the basic principle of EDM wire cutting and EDM forming, both are based on the principle of vertical EDM hand-sensitive corrosion when pulse discharge between electrodes is realized to realize the processing of parts.

Not a cavity rock concept. EDM machine tools are specifically divided into EDM forming machine tools and EDM wire cutting machine tools. The processing principle of the two is the same, both of which use the current positive and negative electrode contact discharge to produce high temperature to melt the metal, so as to achieve the purpose of cutting.

Wire cutting machine tools are divided into fast wire walking and slow wire walking. As the name suggests, it is distinguished by the speed of the electrode wire movement. Fast walking wire is generally used as an electrode wire for recycling. The processing efficiency is relatively high, and the accuracy is low.

The slow wire uses copper wire as the slag electrode wire, which has low processing efficiency and high precision, and generally needs to be cut 3-4 times. High processing costs. Wire EDM uses electrode wires to reciprocate and cut parts like a saw. The disadvantage is that only parts that are connected up and down can be machined.