Study Of Mechanism Of Single Point Diamond Cutting Of Cerium

Cerium has become an important surrogate in nuclear field because of its similar physical and chemical properties with Plutonium.It is of great importance to improve the corrosion resistance ability of this kind of materials in the application of nuclear field.High-quality surface can significantly improve the corrosion resistance of the material.However,it is challenge to obtain the smooth surface due to the unique physical and chemical properties of cerium.Therefore,in this paper we perform molecular dynamics simulation of diamond cutting of single crystal cerium,bicrystal cerium and polycrystalline cerium and preliminary experimental study to investigate the mechanisms of single point diamond cutting of cerium.The molecular dynamics modeling of diamond cutting of cerium is first introduced,especially focusing on boundary conditions,empirical potentials and the ensembles.The structure and properties of different phases of cerium are evaluated by molecular dynamics modeling,and dislocation analysis and phase transformation analysis in the cutting process are studied,which are used to identify the internal defects and phase transition of the workpiece..The deformation mechanisms of single crystal cerium,bicrystal cerium and polycrystalline cerium under diamond cutting processes are studied by using molecular dynamics simulations,with an emphasis on the internal defect structure formation and the phase transition occurred in the cutting process.Simulation results indicate that the mechanisms of single crystal cerium,bicrystal cerium and polycrystalline cerium with different internal microstructures are significantly different from each other,in particular for the internal plastic deformation and phase transitionThe processing parameter has a great impact on the diamond cutting of cerium.Therefore,molecular dynamics simulations are performed to address the influence of processing parameters on the cutting process,including the influence of the tool rake angle,the crystal orientation and the tool geometry on the cutting of single crystal cerium,the influence of grain boundary type and the angle of grain boundary on the cutting of bicrystal cerium,the influence of cutting depth and the size of polycrystalline cerium on the cutting of polycrystalline cerium.Based on the simulation results,the influence of different processing parameters on the diamond cutting of cerium is obtained.Finally,we carry out preliminary experimental study of single point diamond cutting of cerium.First,anti-oxidation storage experiments are carried out prior to cutting.Then,diamond cutting experiments with different cutting depths are carried out by using a home-made ultra-precision machining lathe.After the completion of cutting,cerium is subjected to profilometer detection,atomic force microscope detection,metallographic microscope detection,oxide film thickness detection.The qualitative comparison between molecular dynamics simulation and experimens of diamond cutting of cerium is conducted in terms of cutting depth-dependent cutting status.