Iscar T4-.120-ER54220X 4-Flute TiAlN Steel Roughing End Mill

The Iscar T4-.120-ER54220X is a new, steel roughing end mill from Iscar's ER (Roughing) series, manufactured in PM200 grade — a submicron tungsten steel grade designed for high-performance milling of steels, stainless steels, and heat-resistant alloys. The full part number decodes as follows: T4 = 4 flutes, .120 = 0.120 in corner radius (knuckle/wave tooth profile for roughing), ER = Roughing End Mill, 5 = series identifier, 4220 = 1-3/8 in (1.375 in) cutting diameter with 2-1/4 in length of cut and 1-3/8 in shank diameter, X = extended reach/length variant with TiAlN-based TINAMITE-X coating. The TiAlN-X coating (Iscar's TINAMITE-X) provides excellent oxidation resistance up to ~900 °C, making the tool well-suited for dry and semi-dry high-speed roughing applications. The serrated/wave-tooth (knuckle) cutting edge geometry breaks chips into short segments, reducing cutting forces and enabling aggressive material removal rates in ferrous materials on CNC machining centers. The shank features a Weldon flat for secure toolholder engagement in standard end mill holders.