Surface profile texture characterization of trimmed laminated composite in the stacking sequence direction

• Novel surface profile characterization technique for laminated composite.
• New filtration technique for composites in the transverse direction.
• Proposition of removing profile valleys caused by −45° plies.
• Reduction of the dispersion results and better surface check.
• Use for trimming and drilling surface inspections.

The surface texture characterization of laminate composites is complex due to its heterogeneous structure and to the different stratified surface properties. Profile roughness parameters are highly impacted by those different layer properties, and their distributions are relatively spread out. A new filtering technique is proposed to improve the surface roughness parameter efficiency. To present issues from current filtering methods and to highlight this new approach, profile surface roughness taken from trimmed carbon fibre reinforced plastics samples are inspected in the composite stacking sequence using a contact profilometer. For each measurement, several roughness parameters are calculated. The efficiency of different filtering techniques is investigated through the roughness parameters distribution, calculated for up- and down-milling and for different tool wear. The new proposed technique, based on the separate characterization of plateaus and large deep valleys of the composite surface profiles, is found to be particularly efficient on the down-milling face.