Research On Turning Machinable Ceramics Simulation And Tool Wear Model

Machinable ceramics have many excellent comprehensive properties that are widely used in industry,semiconductor,medical and other fields.But it belongs to the hard to machine material,and the tool wear is serious.In the process of machining,the path of crushing has certain randomness and the cutting force fluctuates greatly.The research focus in this field is to analyze the crushing mechanism of ceramic materials and prevent the tool from excessive wear and passivation.In the process of turning ceramic materials,it is difficult to capture the fracture process by using high-speed camera technology because the crack growth speed is too fast.Based on the theoretical analysis,this thesis divides the machinable ceramics into three areas:small-scale crushing,large-scale crushing and residual stress.JH-2 constitutive model is selected as ceramic material model,and finite element simulation is carried out in ls-dyna software environment.Study the influence of machining parameters on cutting force.The influence of machining parameters on cutting force is studied.The thesis analyzes the wear mechanism of machinable ceramic cutting tools.The tool wear is regarded as the three body wear form of workpiece chip tool.Based on Hertz contact theory,the main form of tool wear is fatigue wear.Based on the mechanism of fatigue wear and the equation of tool tip movement path,the theoretical model of tool wear is established by considering the factors of machining process parameters,tool material parameters and ceramic chip particle radius.The single factor machining experiment was carried out,and the reasonable model parameters were obtained by measuring the ceramic chip radius.The experimentally measured cutting force and tool wear were compared with the simulated cutting force and wear model predicted tool wear,respectively.The validity of the finite element simulation and the theoretical model of tool wear is verified.