The Effect of Tool Structure and Milling Parameters on the Milling Quality of CFRP Based on 3D Surface Roughness

As the performance potential of composite materials continues to be explored, CFRP has gradually become an important candidate material in various fields. However, CFRP is a typical difficult-to-process material because of its anisotropy and inhomogeneity. Inappropriate tool structure or parameters will lead to substandard surface quality. For this reason, a series of experiments are designed in this paper, including tool structure optimization experiment, milling parameter single factor experiment, and milling parameter orthogonal experiment. And because of the complexity of the composite surface, the surface roughness Ra commonly used in metal cutting is not used, but a series of 3D surface roughness indexes are used to evaluate the surface. The effect of process parameters on the processing quality was explored by single variable analysis, range analysis and grey relational analysis. It is concluded that better surface quality can be obtained by using multi-blade cutters with moderate helix angle. Furthermore, Medium feed per tooth is more beneficial to the surface quality. The small depth of cut can effectively reduce the milling force, but when the depth of cut is less than the thickness of CFRP single layer, the surface quality will decline sharply.