Exploring Entegris POCO Materials EDM-1® Graphite
There are a variety of options available when choosing electrode material for sinker electrical discharge machining (EDM), but how can you decide which material will provide the best performance at the best price? In this piece, we’ll be discussing Entegris POCO Materials EDM-1®, one of our most economical Ultrafine graphite grades.
Although this is a budget-friendly option, that’s seldom a good reason for choosing an electrode material. Instead, let’s look at the characteristics of this material and learn why it may be a good fit for some specific applications.
What is EDM-1?
EDM-1 is a grade offered in the Ultrafine class that is a top choice for many electrode designs and mold and die applications. This five-micron grade provides a combination of speed, low electrode wear, and a good surface finish. It offers high performance at a lower cost which reduces overall job cost.
EDM-1 graphite is an efficient material for electrical discharge machining due to its uniform structure, strength, and machinability. Its unique properties enable precise and efficient material removal, resulting in high-quality finished products. Whether it be for mold making or tool and die applications, EDM-1 is very effective in achieving accurate and intricate shapes in the EDM process.
Why Choose EDM-1?
One reason you might choose EDM-1 is due to its uniform material structure, which lends itself to several benefits. If you need speed in the burn, the material creates less debris which allows for better flushing conditions and results in fewer secondary discharges. Its lower Shore hardness means that it is easier to machine and produce complex shapes. This grade is suitable for both rough and finishing electrodes, allowing you to achieve the desired results without needing different materials for each process. This approach minimizes potential errors and reduces overall cost.
What to Look For When Selecting Electrode Materials
EDM-1 is suitable for a wide range of applications, but it’s not a universal fit. When assessing electrode materials for EDM, you’ll need to understand five different factors. Here’s how these factors relate to EDM-1:
- Work Metal Type
EDM-1 performs best in applications that benefit from using positive polarity and longer on-time. Common applications include:- Tool Steels such as H13, S7, D2, P20, and 4140
- Stainless Steels such as 410, 420, and 440
These metals take advantage of EDM-1 graphite’s ability to produce fine details and fine surface finish while maintaining electrode integrity and wear resistance. However, you may run into difficulties if you change the work metal type. For example, if you’re working on an exotic material such as tungsten carbide or a copper alloy, you’ll find that EDM-1 is not the best-performing choice. That’s because it experiences higher electrode wear compared to a copper-impregnated graphite such as EDM-C3®, which has a lower electrical resistivity.
- Electrode Detail and Size
With an average particle size of less than 5 microns, EDM-1 provides both strength and resistance to damage. Due to its lower Shore hardness, this material can be machined into more intricate shapes. However, in applications where thin cross sections and high flexural strength are required, you’ll likely need to upgrade to a higher strength Entegris POCO Materials grade of graphite. - EDM Performance
EDM-1 is a 5-micron material produced by Entegris POCO Materials, so users benefit from the same consistency and wear performance expected from all of our EDM grades. It has excellent end wear performance, consistently below 1%, resulting in better electrode life. Lastly, EDM-1 can create surface finishes down to 18 VDI. - Cost
EDM-1 offers additional cost benefits. Its excellent wear resistance extends electrode life, reducing the number of electrodes needed to produce the detail which allows for lower consumable costs and machine time both in electrode fabrication and sinker EDM. EDM-1 graphite’s strength and consistent structure enable faster machining speeds and better surface finishes, leading to shorter production times and lower labor costs. - Physical Characteristics
In addition to its uniform material structure, EDM-1 offers a typical flexural strength of 9700 psi and 69 Shore hardness. This is beneficial when fabricating electrodes with good detail. The uniform structure of the material, plus its strength and low hardness range, allows for the fabrication of electrodes in configurations where other materials tend to chip or break completely. Examples of this include ribs, posts, or other fine details. Entegris POCO Materials users can optimize machine settings in fabrication and EDM, enabling the operator to be more aggressive.
Work with Entegris POCO Materials to Find the Best Electrode Materials for Your Application
Graphite is a top performer in multiple sinker EDM applications because of its ease of machinability, performance, and lower cost. Entegris POCO Materials offers excellent graphite material for EDM sinker applications and has been a standard in the industry for over 50 years.
Using graphite from Entegris POCO Materials means that you’ve joined a partnership that’s dedicated to helping you succeed. In addition to free virtual and in-person training, we also offer application support that can help you dial in program settings for optimized performance. Contact an applications specialist and learn how you can excel with graphite from Entegris POCO Materials.
