Features for EDM Graphite

 

EDM(Electrical discharge machining) Technology is playing a more and more important role in precision mold processing. The selection of EDM electrode materials was also attracted great attention.

 

Graphite is a important material to EDM because using graphite as a conductive material result. As we all know, the selections of the electrode materials are electrolytic copper, copper tungsten, silver tungsten, the traditional graphite etc. Hog in longer-lasting EDM electrodes and remove metal more quickly. However, for the comprehensive consideration of the quality, cost and efficiency, most of the mold manufacturers choose the electrolytic copper as the common electrode materials. But with the development of the industry and technology. Higher quality, lower cost and faster delivery become the constant theme among the mold- making plants. The new graphite material attracts the mold manufacturing engineers sight at a proper time, in addition, its high quality, great efficiency and the low cost also meet the engineers pursuit in a almost perfect way.

 

Many engineers who are entered in to the mold processing industry earlier and contacted the graphite material had a general impression: dirty, easy to fall slag, poor machining accuracy, low efficiency, and etc. At that time, only when worse comes to worst or the demand of the mold manufacture quality is not high that people would consider it.

 

However, with the upgrade of the technology, a new graphite material-isostatic graphite leaves a different impression for people. Its high strength and high density such processing characteristics can be used in extraordinary precision parts and also can be used in the process of complex shapes oversize parts. Its processing speed is amazing. This is what we saw: The isostatic graphite materials are wildly used as the electrode materials in Auto mold, household appliances and cell phone mold. The quick test of the high quality mold and quantity production for the mold factories comes true. It enhance the competitiveness of the mold manufactures.

 

http://www.topgrafit.sk/en/graphite-products/electrical-discharge-machining-edm-/

Advantages of Graphite Electrode
Weight of graphite is 4-5times lower	r=1,80g/cm3(graphite) vs. r=8,93g/cm3(cooper)
Easier Machining Properties	The mechanical processing speed for graphite electrode is 2-3 times than copper electrode..
Low Thermal Expansion	The melting point of copper is 1080°C while graphite is 3650°C. CTE is 1/30 less than Copper.
Stable and Affordable Price	The copper electrode is priced much lower than graphite.
Higher Removal Rate	1.5-3 times higher than utilizing Cu Electrodes.

 

Features

 

Stable and Affordable Price

The graphite material price only takes 15% of the copper electrode with the same volume. Graphite has become a popular material for EDM application. Graphite material cost is lower and more stable.

 

Good Machinability

Graphite has excellent mechanical machining properties. The mechanical processing speed for graphite electrode is 2-3 times than copper electrode and no burr after processing. 

 

Low Coefficient of Thermal Expansion

The melting point of copper is 1080°C while graphite is 3650°C. CTE is 1/30 less than Copper. It is stable even under ultra high temperature. It has an obvious advantage on the platinum electrode process. 

 

Light Weight and Low Density

The density for graphite is normally 1.7-1.9g/cm3 (4-5 times less than copper). Compared with copper electrode, graphite electrode will reduce the mechanical load during the process. It's more suitable for application for large mould.

 

Good Machinability

Compared with metallic materials, the bulk design of graphite is lower. It has excellent mechanical machining properties.

 

Good bonding effect

The broken graphite can be stuck by adhesive and it saves time and material costs.

 

Excellent Electrical Resistivity

Electrical Resistivity(ER) determines the material's resistance to the flow of an electrical current. With lower ER, which means better conductivity.

 

High Purity Molded Graphite also has other good characteristics for EDM applications such as:

 

• Average Grain Size
• Flexural Strength
• Hardness
• Excellent Anti-corrosion,

Properties Data

 

Our EWD Graphite with a grain size ranging from a few microns to about 20 microns. XRD Graphite has a good range of properties and performance characteristics of the various EDM material. This enables you to choose most suitable grade for your application. For properties of popular XRD sizes please see table below: