Research On NC Milling Process Simulation And Integrated Optimization Of Complex Curved Surface

With the development of science and improvement of economic level,Complex surface parts are used more and more widely in the field of mold,tool,energy,transportation,aerospace,navigation,etc.Common complex curved surface parts are sculptured surface parts,ruled surface parts,covering parts and composite surface parts,ect.Such parts own complex shape,large curvature,high spatial distortion degree,and thin wall structure,the processing of which are very difficult.Multi axis NC milling machining equipment and its technology provide an effective processing method of complex curved surface parts.The common complex surface machining methods mainly include the modeling of complex surface,milling method,cutter axis attitude control,tool path calculation,post-processing technology,NC machining process simulation,optimization and so on.However,the current researches on NC milling of complex curved surface parts are lack of integrated optimization methods for multi process parameters,multiple optimization objectives.A process simulation and integrated optimization platform that can support the CAD-CAM-CNC data link model has not been built yet.Taking the turbine blade as an example,the characteristics of complex free-form surface and the difficulties to predict the quality of NC Milling are analysised,based on which the cutting quality analysis method according to the simulation of milling process and integrated optimization is proposed.Firstly the main process parameters,milling behavior,performance quality and influence relationship of the complex surface multi axis milling are analysised.The digital model of turbine blade is established,the NC milling process planning scheme is put forward,based on which tool path calculation is done and multi axis milling simulation model is founded.Then the integrated framework of multi axis NC milling process simulation and multi axis milling process system integration interface are built based on the multidisciplinary optimization platform:OPTIMUS,and an integrated data link model for multi axis milling of complex surface is established.Finally,the surface milling quality and cutting force of the turbine blade are taken as the optimization objective.The cutting speed,feed rate and cutting depth data are used as input files,based on which the 455 groups of integration simulation data are calculated.The experimental design of simulation data for milling process simulation is given as the basis of that the response surface model of milling parameters and milling optimization objectives is established.Finally,optimum process parameters for multi axis milling are put out under the simulation environment of this paper.The variation rule of process parameters in multi axis milling of complex surface is exposed.The influence of different processing parameters on the milling quality of complex curved surface is analyzed quantitatively.The timely feedback and adjustment of process information are realized.Simulation time is shortened and the accuracy of surface milling quality analysis is improved.To sum up the research is of great theoretical significance and application value to improve the NC milling quality of complex curved surface parts.