Experimental Study Cutting Performance Of Step Drill Drilling CFRP/Ti6Al4V Stacks

The use proportion of CFRP is getting higher and higher in the aircraft.In the process of aircraft assembly,commonly used bolts and rivets between Carbon Fiber Reinforced Polymer and titanium alloy together to enhance its mechanical properties.so large number of connection holes are need for CFRP/Ti6Al4 V laminated board.However,Carbon Fiber Reinforced Polymer and titanium alloy mechanical properties vary widely in the processing of CFRP/Ti6Al4 V laminated plate process,the Carbon Fiber Reinforced Polymer layer will appear many defects such as tearing,burning,stratification and hole wall scratches,so the quality of the processing hole is difficult to guarantee.Based on the defects in the process of making hole of the CFRP/Ti6Al4 V laminated plate,the drilling experiments of the Carbon Fiber Reinforced Polymer,the titanium alloy and the CFRP/Ti6Al4 V laminated plate were designed.In this paper,the drilling force,the hole outlet quality and the surface roughness of each hole under different cutting parameters were studied and compared with the ordinary twist drill bits,which provides some experimental basis for the research of the subsequent processing theory and process.The main work are as follows:(1)The drilling force of Carbon Fiber Reinforced Polymer was studied by using single-factor test method.The drilling force,hole export quality and hole wall surface roughness were studied under different cutting parameters.And contrast with ordinary twist drill bit.The effects of different diameters on the axial force of the drilling tool are analyzed.(2)The work ability of the titanium alloy was studied by using the four kinds of stepped drill and an ordinary twist drill.The drilling experiment was carried out and compared with the ordinary twist drill.The effects of different processing parameters on drilling force,pore size,hole surface roughness and hole entry and exit were studied.The effects of different diameters on the axial force of drilling were studied.(3)The drilling experiment of CFRP/Ti6Al4 V laminated board was carried outwith the preferred step drill and compared with ordinary twist drill.The effects of drilling force and titanium alloy chip shape on the quality of the hole were analyzed.The drilling force,pore size and the quality of the hole and inlet were studied under different processing parameters.Finally,through the tool wear test,studying the wear law of the step drill.