What is EDM?
In contrast to cutting, which uses a machine tool such as a machining tool or lathe to cut metal, EDM is a method of processing hard metal using energy that emits electricity and acts as a tool. cut.
The discharge between the metal and the metal creates a discontinuous spark about 1000 to 100,000 times per second, and by releasing it, the metal surface is scraped by the heat and impact, changing shape little by little Let me do that.
The sparks produced between the metals reach 6000 degrees and are processed in pure water or oil to create sparks, cool the metal, disperse the molten metal and create an insulating state.
Unlike cutting, it is contactless, so it can be processed without imposing a load on the material, allowing for easy processing with high precision without deformation.
Types of electrical discharge processing
There are two types of EDM, wire EDM and sink EDM.
In wire discharge machining, an electrical wire made of brass with a diameter of about 0.02 to 0.35 mm is used as the electrode, and the metal is scraped with sparks from the discharge.
Can work with conductive materials, and it is suitable for very long shapes and thin cuts that are difficult to cut.
In addition, because the processing is carried out during continuous cooling, there is no thermal deformation and it is also used to process extremely thin metals.
Furthermore, if it is a current-carrying material, it can be processed regardless of its hardness and can be machined with precision, making it possible to machine cemented carbide.
Although it is possible to perform difficult machining with high cutting and machining precision, there is a part in cutting in terms of machining speed, so it is not suitable for mass production.
In submerged discharge machining, copper or graphite can be used as electrodes to process the metal by digging with sparks from the discharge, and the shape of the electrode can be transferred to the metal to be processed.
Unlike wire discharge machining, it uses a special electrode according to the machined shape and does not need to penetrate the wire electrode, so many different shapes can be transferred, and even a bag has a bottom that can be processed, thus having a high degree of freedom it can be processed into a shape that cannot be achieved by cutting.
Since there is a risk that the finished shape of the workpiece will be lost due to wear and tear during processing, when the electrodes have corners, it is necessary to prepare multiple electrodes and replace them to increase processing accuracy.
Materials suitable for electrical discharge machining
Can work on hard metal materials such as molybdenum, inconel, titanium and carbide, which are difficult to cut.
Unlike cutting, it uses sparks that use electrical discharges between metals instead of cutting blades, so it can handle shapes well regardless of hardness.
EDM Applications
It is also used in molds and stamping dies, such as molds for efficient and stable production objects commonly used in everyday products, as well as in nameplates, blades, models and aircraft parts.
It is used in a huge variety of applications, from tools and automobiles to new materials, semiconductors, aerospace and medical technology.
Surface roughness after ED
In wire discharge machining, the wire is strongly oscillated and the spark caused by the discharge is crushed by hitting the metal, so that the machined surface is finished in a rough surface such as a satin surface.
The finish of the machined surface depends on EDM conditions, wire speed, servo voltage, wire tension, etc., but it is finished with a surface roughness of about Ra18μm to Ra3μm.
To improve surface roughness requires careful and time-consuming treatment.
Even if you care about surface roughness, it is possible to complete the surface roughness and precision more precisely by grinding after wire discharge machining.
At Metal Speed, we can offer everything from material procurement to discharge machining, subsequent grinding and surface treatment.
Metal Speed supports various processes such as milling, machining and turning.
Please for metal machining, aluminum machining, stainless steel machining and metal machining for Metal Speed.
We supply high quality metal parts from Osaka and Tokyo nationwide with short delivery times.
