Experimental Analysis On Micro Cutting Of Polycrystalline Metals And Experimental System Development

Micro cutting has the advantages of high efficiency,high precision and low machining cost,and it's not limited by processing materials,Micro-cutting has become an important direction in the field of micro-manufacturing.The research of micro cutting experiment and mechanism is significant to optimize micro cutting process and improve surface machining quality.In the micro-cutting process,the radius of the micro-tool edge is in the same order of magnitude as the depth of cut and the grain size of the workpiece material,so the radius of the edge of the tool has a significant effect on the micro-cutting process.In order to study the micro-cutting process deformation mechanism and the effect of microstructure on the formation of micro-chip,a micro-cutting experimental system was designed and developed.A series of micro-cutting experiments were carried out for polycrystalline metals.The experimental system is mainly composed of feed module,observation module,test module,control module and clamping module,which can realize the orthogonal cutting of small metal sample,the cutting speed can reach 25 mm / s,Observation module can observe and record the micro-cutting process,while enabling rapid cutting tool adjusting.The dynamic characteristics of the system are analyzed by finite element method,the vibration characteristics of the system were evaluated by Doppler vibrometer,the analysis results show that the system has good stiffness and anti-vibration performance.The reliability of the system was verified by testing the surface roughness of micro-machined specimens.Further improvement and design scheme are put forward.Polycrystalline metals(SUS304,Cu,Al and Tc4)cutting experiments were carried out to study the deformation of grain structure,the change of chip,and the grain size of the metal cutting process,study the grain crystal in the process of metal cutting deformation and chip root change,grain refinement etc,as well as the influence of different process parameters on cutting force,work hardening and surface roughness,and provide experimental data support for the future micro-cutting theory and process research.