TUNGSTEN CARBIDE END MILLS ARE USED IN MANY APPLICATIONS FOR MACHINING NONFERROUS MATERIALS, SUCH AS HIGH SILICON ALUMINUM, GRAPHITE COMPOSITES, OR WOOD. END MILLS MADE WITH STANDARD OR FLAT PCD HAVE HAD LIMITED SUCCESS IN THESE APPLICATIONS BECAUSE THE TOOL GEOMETRY ALLOWS SEVERE INTERRUPTED CUTTING. THIS RESULTS IN A POOR SURFACE FINISH OF THE PART AND A CHIPPED PCD CUTTING EDGE. A HELICAL PCD END MILL HAS BEEN DEVELOPED TO PROVIDE A MORE NATURAL CUTTING GEOMETRY FOR MILLING OPERATIONS. TEST RESULTS SHOW THAT HIGH CUTTING SPEEDS AND FEEDS, AS WELL AS SURFACE FINISH, CAN BE ACHIEVED WITH A HELICAL PCD END MILL.