Research On The Removal Mechanism Of Roller Non-resonant Vibration-assisted Polishing

With the rapid development of today's society,medical instruments,aerospace vehicles,military and defense and other scientific and technological fields have higher and higher requirements for materials,such as silicon carbide,zirconia and other difficult-to-process materials with excellent material properties are widely used.Generally,difficult-to-machine materials require grinding and polishing as the final process to meet quality requirements.However,the traditional polishing process may produce irregular damage on the surface of the experimental workpiece,such as scratches,pits and microcracks.In summary,in order to comply with the application requirements of difficult-to-process materials in the national high-tech fields.This paper develops a set of decoupling vibration polishing device applied to the roller polishing method,establishes a mathematical model of polishing force and material removal rate,and conducts process parameter experiments to analyze the feasibility of the roller vibration assisted polishing method.The main research contents of the thesis include:(1)Computer-aided design of decoupling vibration polishing device.Based on pseudorigid body method,flexibility matrix method and Lagrangian method,the static performance and dynamic performance of the decoupled vibration polishing device are modeled respectively.In addition,the structural size of the decoupling vibration polishing device is optimized based on the gray wolf algorithm,and the purpose is to increase the stroke space of the decoupling vibration polishing device on the basis of maintaining the existing natural frequency of the decoupling vibration polishing device.(2)Based on the finite element analysis method,respectively simulate the dynamic and static performance of the decoupling vibration polishing device,including: stiffness performance,maximum stress,coupling rate,stroke space,natural frequency and mode shape.Then,the device test experiment is performed to determine the working performance of the decoupled vibration polishing device,including: resolution,natural frequency,stroke space,coupling rate,step performance and hysteresis performance.(3)Carry out the motion trajectory analysis and mechanical analysis of the polishing particles under the action of vibration,comprehensively integrate the material properties of the polishing particles and the polishing pad,and establish the polishing force model and the material removal rate model of the roller vibration assisted polishing respectively.The polishing force model mainly considers the contact state and interaction relationship between the polishing particles and the experimental workpiece;the material removal rate model mainly considers the penetration depth of the polishing particles,the movement speed and the number of active polishing particles.(4)Conduct variable load and constant load scratch experiments to analyze the material removal form of typical difficult-to-machine silicon carbide by polishing particles under different loads.Perform variable parameter processing experiments to modify the theoretical models of roller vibration-assisted polishing force and material removal rate and verify the effectiveness of the polishing force model and material removal rate model.The experimental results were tested,and the effectiveness of the decoupling vibration polishing device applied to the roller polishing method was discussed.