Research On The Machining Characteris Of Al₂O₃ Bioceramic Materials Based On The Discrete Element Methed

Al₂O₃ bioceramic has excellent chemical stability and biocompatibility,as well as high hardness and good wear resistance.It is widely used in artificial joints and is extremely stable in human body.However,the surface and subsurface damage of Al₂O₃bioceramics are easily produced during the process of processing,which leads to premature failure of artificial joints.Therefore,according to the processing characteristics of Al₂O₃bioceramic materials,selecting reasonable processing parameters,reducing the number and depth of cracks produced by ceramic materials in machining process is the key to improve the service life and machining accuracy.Based on discrete element method,the generation and propagation of cracks and the change of cutting force during dynamic processing are simulated.The number of cracks and the depth of cracks under different processing conditions are studied.The processing parameters of Al₂O₃ bioceramics are optimized based on the number of cracks and the depth of crack.The main work of this article is as follows:1,Based on the discrete element method,the BPM model of Al₂O₃ bioceramic material’s mechanical properties is established by comparing the simulation results and measured results of macroscopical properties of materials and modifying the microscopic parameters of particles.2,Establishing two-dimensional cutting model and 3D micro milling simulation model of Al₂O₃ bioceramic.Analysising the influence of different processing parameters on the number of cracks,the depth of crack and the cutting force during the cutting process of Al₂O₃ bioceramics,and a set of optimized process parameters is obtained.Analysising the influence of cutting factors on milling force Fx,Fy and Fz in three directions.3.The experiment of micromilling of Al₂O₃ bioceramics was carried out.Analysising the influence of micro milling parameters on milling force of Al₂O₃ bioceramic in milling process,and the simulation results and milling experimental results,observing the surface quality of workpiece after machining.Verifying the rationality of the three-dimensional discrete element model and cutting process of Al₂O₃ bioceramics.