These mills are more appropriate for high-speed machining (HSM) processes on harder materials like steelsaver 4140 steel, which can have a hardness of as much as 50 HRC, mainly because of their rotary cutting tools which are made with carbide flutes. The milling cutters (also referred to as end mills) are configured from 2 to 6 flutes and have an additional 30 to 45 degree cutting helix angle which further improves the ejection of chips and flakes, as well as corner contours ranging from radii 0.2mm to 5mm. The cutting edges of aluminum alloys compatible with the aerospace industry withstand temperatures up to 1200 degrees celsius and allow feeding up to 3000 mm/min when using 2 to 4 micron thick AlTiN coated tools.
