POCO Graphite, Inc. (Decatur, TX) introduces EDM-4 graphite for EDM electrodes, which is now the premium material in the Ultrafine classification, offering improved wear and surface finishes during finishing operations. For mold shops that need higher performance, POCO developed EDM-4 with a smaller grain size and higher strength than EDM-3. EDM-4 is ideal for applications with extreme tolerances in medical, automotive, semiconductor and aerospace industries. In some cases, end users report 10 to 15 percent improvement in wear on finishing electrodes with improvements in surface finishes. EDM-4 electrodes can improve the EDM performance when producing thin, deep slots and critical features or tight tolerances in cavities or parts.
For all-purpose mold work, the material EDM-3 is a popular graphite grade in the Ultrafine (1 to 5 micron) classifications for plastic injection mold cavities. It has the performance characteristics of high strength, uniform microstructure and small particle size to provide outstanding electrode and fine surface finishes.