Study On Cutting Temperature In Elliptical Vibration Cutting

Elliptical Vibration Cutting(EVC)is an efficient special cutting machining method.The elliptical vibration signal drives the tool holder so that the tool moves in accordance with the elliptical trajectory,thereby realizing high-frequency intermittent vibration cutting,which can effectively improve the cutting processing.It is applied to ultra-precision machining of hard-to-cut material(HCM).Although the predecessors have already made a lot of research on EVC technology,the cutting temperature in the machining process has not yet been clearly revealed,which affects the research on residual stress,tool wear and service life,surface quality and performance after machining,etc.On this basis,this paper studies the EVC cutting temperature from theoretical models,simulation analysis and elliptical vibration assisted turning experiments.First,the EVC process is discretized in one cycle,and the relationship between cutting velocity,shear velocity,and chip flow velocity as well as the shear force and the rake face friction force in the EVC process is revealed by real-time changing cutting depth,tool rake angle,and shear angle.For the characteristics of intermittent cutting and friction reversal in the EVC process,the heat generated per unit time is regarded as the plastic deformation work of the shear surface and the friction work on the rake face.Based on this,the temperature rise and the heat distribution ratio of the cutting tools,workpieces and chips are discussed.Secondly,under the environment of finite element simulation software ABAQUS,the cutting process of TC4 titanium alloy with carbide tools was simulated,and the finite element simulation model of EVC was established to simulate the changing process of cutting temperature.The simulation analysis results show that the X-direction amplitude is negatively correlated with the cutting temperature;Y direction amplitude,cutting depth,tool nominal rake angle are positively correlated with the cutting temperature;With the increase of cutting speed,the variation of cutting temperature rise and fall also increases.A comparative analysis of the tool wear rate model for wear patterns such as abrasive wear,adhesive wear,and diffuse wear.The secondary development language Python was used to extract the parameter variables such as temperature,stress,and blade-to-chip relative slip speed in the EVC simulation model in the ABAQUS software environment.They were applied to the calculation of total tool wear and fed back to the simulation model.This simulates the tool wear profile under certain cutting conditions.Finally,an experimental system was set up on the Nanoform 250 ultra-precision lathe to conduct elliptical vibration assisted turning temperature experiments.The aluminum round bar stock and TC4 titanium alloy bar stock are processed.Using an infrared camera to collect real-time cutting temperature data,compare the cutting temperature of different materials and cutting conditions.The depth of field of the tool after different cutting lengths was observed using an ultra-deep-depth microscope system.Collation and comparison with the simulation prediction model verify the correctness of the theory and simulation model.Through the research of this paper,it can provide theoretical basis for studying the elliptical vibration cutting residual stress and tool wear.