Milling cutting speed refers to the instantaneous speed of a selected point on the cutter relative to the corresponding point on the workpiece.
Vc = πDN/1000
Vc: Cutting speed (m/min)
N: Cutter rotational speed (r/min)
D: Milling cutter diameter (mm)
Cutting speed is influenced by factors such as cutter material, workpiece material, the rigidity of machine tool components, and cutting fluids. Lower cutting speeds are typically used for machining hard or tough metals-a process known as heavy-duty cutting-to reduce cutter wear and extend tool life. Higher cutting speeds are generally used for machining softer materials to achieve superior surface finish quality. High cutting speeds may also be employed when using small-diameter cutters for micro-machining operations on brittle materials or precision components. For example, when using high-speed steel (HSS) cutters, the cutting speed is 91–244 m/min for aluminum and 20–40 m/min for bronze.