Carbon fiber reinforced polymer (CFRP) is a typical difficult–to–machining material. There are still some problems in its milling process

such as the poor surface quality and difficulty in fully characterizing the surface topography. In this article

slot–milling tests were carried out with different feed speeds

and the surface topography and machining mechanism of CFRP milling was studied. It was found that there was a big deficiency using two–dimensional surface roughness parameters

three–dimensional surface roughness can more comprehensively reflect the surface topography of CFRP milling. The surface topography of CFRP was jointly characterized by arithmetic mean height S

a

root mean square height S

q

skewness S

sk

and kurtosis S

ku

. With the increase of the feed speed

S

a

and S

q

increase gradually

but S

sk

and S

ku

decrease. In order to guarantee the machined surface quality

the down milling method is used

and the feed speed should be less than 1200mm/min.