Uncoated High-Speed Steel—Use uncoated end mills for general purpose milling and short production runs.

Titanium Nitride (TiN)-Coated High-Speed Steel—Titanium nitride (TiN)-coated end mills create less friction than uncoated end mills, which means they last longer when run at similar speeds. Use coated end mills for demanding, high-speed jobs in hard material as well as for longer production runs. They’re more wear resistant than uncoated end mills.

Titanium Carbon Nitride (TiCN)-Coated High-Speed Steel—Titanium carbon nitride (TiCN)-coated end mills have a hard, smooth finish that resists chipping and wear and prevents material from accumulating on the cutting edge. They’re especially good for use on aluminum. Use coated end mills for demanding, high-speed jobs in hard material as well as for longer production runs. They’re more wear resistant than uncoated end mills.

Titanium Aluminum Nitride (TiAlN)-Coated High-Speed Steel—Titanium aluminum nitride (TiAIN)-coated end mills dissipate heat better than other end mills, especially at high speeds. At high temperatures, the coating creates a layer of aluminum oxide that transfers heat to the chips, keeping the tool cool, even when used without lubrication. Use coated end mills for demanding, high-speed jobs in hard material as well as for longer production runs. They’re more wear resistant than uncoated end mills.

2 Flutes—End mills with two flutes provide better chip clearance for high-volume, high-speed plunge, slotting, and roughing cuts.

4 Flutes—End mills with four flutes provide a finer finish and operate with less vibration when run at high speeds.