Comparative Research On Cutting Performance Of Multi-edge Milling Cutters With Different Micro-tooth Shape In Machining CFRP

Carbon fiber reinforced polymer(CFRP),a very typical high-strength and light-weight material,has high specific strength and high specific stiffness and its material properties can be parameterized according to the actual application requirements.In order to satisfy the assembly requirements,secondary operations such as milling are needed after complex parts are directly realized through near-net shape.With the increasing use of CFRP in various fields,higher and higher requirements are put forward for milling cutter structure.Milling cutter structure is an important factor affecting its cutting performance.In the machining of CFRP,the machining efficiency of the multi-edge and micro-tooth milling cutters is greatly improved compared with the integral edge milling cutters,and the application of the multi-edge and micro-tooth milling cutters is becoming more and more extensive.The main purpose of this thesis is to establish a prediction model for milling force of multi-edge and micro-tooth milling cutter milling CFRP multi-directional laminates.Based on comparison results of cutting performance differences between multi-edge and micro-tooth milling cutter and integral edge milling cutter in milling force,burr,surface topography and surface roughness,we change the geometric structure of the multi-edge and micro-tooth milling cutter to improve the cutting performance.The main work of this thesis includes the following points:(1)A prediction model of milling force is established for cutting CFRP multi-directional laminates with multi-edge and micro-tooth milling cutter.The model is based on the instantaneous rigid force model,considering the problem of different micro teeth of multi-edge and micro-tooth milling cutter correspond to a different fiber angle layers which have different cutting force coefficients.(2)Milling experiments using differents milling cutters with different cutting edge shapes and cutting edge circumflex on four typical fiber angle uni-directional laminates and multidirectional laminates were carried out under the same cutting parameters.(3)The cutting performance of different micro tooth shapes of multi-edge and micro-tooth milling cutters is compared.The micro tooth shape is changed by changing the angle of the helix of the chip groove and the cross section shape of the chip groove.By comparing the cutting performance of multi-edge and micro-tooth milling cutters with different angles of the helix of the chip groove,the optimal angle of the helix of the chip groove is obtained when the other geometric parameters of the cutters are constant.By comparing the cutting performance of multi-edge and micro-tooth milling cutters with different cross section shapes of the chip grooves,a better cross section shape of the chip grooves suitable for cutting is obtained.