Mechanism And Experimental Study On Hole Cutting Processing Of CFRP

Carbon Fiber Reinforced Plastic，CFRP，being characterized by excellentcombination property，such as greater performance than traditional materials ofstrength, stiffness, anti-vibrating, shock absorption, heat-resistant, programmability,have broad application prospects in aviation, aerospace, national defense, automobile.However, the mechanical processing of CFRP is difficult, especially the fact that a lotof hole processing is needed. Therefore the focus on improving the quality of CFRPhole processing is made hole is of great significance.First of all, a review is made about cutting processing, cutting tools, FEM, andthe main processing defects. The main processing defects include Tear, burrs,delamination in import and export, crack, delamination, poor integrity of hole wall.Secondly，binary cutting model of unidirectional CFRP is made. It turns out thata high integrity of hole wall can be achieved when, the angle of cutting speed andparallel to fiber layer, is0, and a poor integrity can be achieved when=135°for apositive rake angle and0°<<90°for a negative rake angle. Analysis is made aboutdrill process and influence factor and ways to thrust force. Critical thrust forces ofdifferent tool that can lead delamination are calculated and a introduction of helicalmill.At last, influence is analyzed in detail of cutting tools and parameters on thrustforce, process defects and tool wear through both FE (ABAQUS) and experimentalmethod.The result shows that the defect in export is more serious than import and microcracks and delamination can be observed on the hole wall. Twist drill with a high rakeangle, helical milling, step drill and brad drill perform better than traditional twist drillreducing the defects. Axial force, hole defects and surface roughness of hole wall are increased with the increase of feed, and decreased with the increase of spindle speed.Furthermore, feed influents axial force and hole defects more than spindle speed, andthe latter influents surface roughness of hole wall more than the former. The maindefects of cemented carbide tool in hole process are abrasive wear, edge chipping andchip adhesion.