Optimization Of Milling Process Parameters For Aviation Carbon Fiber Reinforced Ploymer Resin Matrix Composites

Carbon fibre reinforced resin matrix composites have excellent mechanical properties such as high specific strength,high specific modulus,high temperature resistance and corrosion resistance.Therefore it is widely used in aerospace,military,automotive track,sports and leisure and other fields.However,due to the anisotropic,imhomogeneous and high hardness characteristics of the material,it is prone to causing severe tool wear,poor machining quality,delamination and tearing damage if the cutting parameters are not selected properly during mechanical processing.Therefore,it is necessary to carry out research on the milling process of carbon fibre reinforced resin matrix composites and select suitable milling process parameters to improve the processing efficiency and processing quality,in order to provide a basis for the selection of milling process parameters for carbon fibre composites.Taking carbon fibre composite unidirectional laminates as the research object,a combination of finite element simulation and milling experiments is used to study the influence of milling parameters on cutting force and surface roughness.Finally the milling parameters are optimised by multi-objective optimisation considering both surface roughness and machining efficiency.The main contents are as follows.(1)In terms of finite element simulation model,the constitutive relationship and failure criterion of carbon fibre composite unidirectional laminates are analysed.Based on the mechanical model of orthotropic materials,a macroscopic model for milling of carbon fibre composites was established.The cutting state,stress distribution,tool temperature and cutting force variation laws during the milling process were discussed.(2)In terms of milling experiments,a three-factor and three-level orthogonal milling experiment for carbon fibre composite unidirectional laminates was carried out in Beijing Jingdiao high-speed machining centre to analyse the effects of milling parameters on cutting forces and surface roughness during high-speed milling cutting.The established finite element simulation model was verified to be accurate and reliable,and the empirical formulas of cutting force and surface roughness were fitted using the experimental data.The experiments show that the use of high-speed cutting can effectively improve the cutting efficiency and surface quality for the difficult-to-cut material such as carbon fibre composites.(3)In terms of process parameter optimisation,the multi-objective evolutionary algorithm based on decomposition(MOEA/D)was used to carry out multi-objective optimisation of carbon fibre composite milling parameters.With minimum surface roughness and maximum material removal rate as the optimisation objectives and spindle speed,feed speed and radial feed as the design variables,the MOEA/D algorithm was used to carry out multi-objective optimisation.The Pareto front with uniform distribution was finally obtained and different positions on the frontier represent different emphases on the two optimization objectives.Finally,the optimised process parameters were verified by experiments.In this paper,the optimization of the milling process parameters of carbon fiber reinforced resin matrix composites is analyzed,and the experimental analysis of the milling process is carried out using high speed cutting technology for carbon fiber composites,a difficult material to machine.The proposed milling process and process parameter optimization scheme for carbon fiber composites can provide reference for future research related to the milling of carbon fiber composites,and the optimized cutting process parameters can provide reference for production practice.