Improved Wear Resistance
EDMing Carbides can be a rough business. Literally. Determining the right set of parameters for job success can require time, attention, and careful fine tuning. And unless you have an excellent working relationship with your machine supplier support team, you’ll have little luck there–especially if you’re working against the clock.So, we thought we’d make things a bit easier. In this Blog Series on EDM Electrode Materials, we’ll discuss 5 ways that you can improve your Carbide EDMing processes with a Copper Tungsten electrode.
What is Wear Resistance?
Now it’s fairly common knowledge that EDMing Carbides is slow going, and as such wear rates can be abysmal. So, it’s crucial to know the wear resistance of your electrode material. Before we discuss the wear resistance of Copper Tungsten, let’s first define how we measure wear. Determining wear resistance primarily means measuring end wear and corner wear.
- End wear is the amount of material burned away from the bottom of the material to the depth of the electrode to the cavity.
- Corner wear is a measure of the length lost of the 90-degree external corner of an electrode to the corresponding internal corner. Together these measurements dictate how successfully a material will perform throughout the duration of use.
What Copper Tungsten Properties Improve Wear Resistance?
Because EDM is a thermal process, the higher the melting point of the material, the better it can withstand the inherently high temperatures of the process. At 6,191°F, Tungsten has the highest melting point of any metal and as such it offers truly unmatched thermal resistivity. Ultimately this translates to better corner wear rates. For applications where sharp corners and detailed cavities are a must, the composition can be adjusted to include more Tungsten to improve performance. (But be mindful that less copper means slower cut rates).The structural integrity of Copper makes it highly resistant to DC arcing in poor flushing conditions, where it can still produce very fine surface finishes. For smoother burning and better surface finish, material composition can include more Copper.
Combining the thermal resistivity of Tungsten with Copper’s resistance to DC arcing makes for an electrode that can hold up in sharp corners and help prevent pitting for EDMing carbides. By using a Copper Tungsten electrode for your carbide EDMing applications, you can ensure production efficiency and cost savings resulting from the improved wear ratio of electrode to workpiece material.
For more on Copper Tungsten blanks for Sinker EDM applications, download our free whitepaper!