Process parameters effect on cutting forces and geometrical quality in thin wall micromilling

Micromilling is one of the most geometrically versatile tooling processes, in fact three-dimensional features can be effectively manufactured on molds and dies achieving a good accuracy performance. Typical and challenging features for these microcomponents are high aspect ratio thin walls. The present study evaluates the effect of wall thickness, milling strategy and tool path on cutting forces in 0.4% carbon steel (C40) thin wall micromilling. An experimental campaign has been designed in order to statistically analyse the cutting force responses and a proper technique (ANalysis of COVAriance) has been applied to remove the tool wear effect. Considerations drawn in the present paper on micromilling cutting forces have been coupled with previous knowledge of the same authors, regarding the process parameters direct link with the thin wall geometrical quality, in order to study the feasibility of a general approach able to meet tolerances by controlling forces.