The Effect Of Ultrasonic Cutting Of Honeycomb Composites On The Resonant Frequency And Amplitude Of Disc Cutter The Acoustic System

The Nomex honeycomb composites are widely used in aerospace manufacturing,national defense,industrial,manufacturing,packaging and other fields because of their advantages such as light weight,high strength,high rigidity,compression,stability,low cost and environmental protection.The Nomex honeycomb composite material is a porous honeycomb structure of the fiber material,compared with ordinary materials,it has complex and special structure,so its processing there will be some difficulty.The Nomex honeycomb composite material applied in high speed milling of traditional will cause the honeycomb fracture,collapse and other poor processing quality,low efficiency and other issues,and will produce large amounts of dust which is harmful to human body.Ultrasonic machining has the characteristics of small cutting force and high machining accuracy.The method of ultrasonic assisted cutting is applied to the processing of the Nomex honeycomb composite material,and it can effectively overcome the shortcomings of traditional high speed milling by using high frequency vibration.At present,the research on ultrasonic cutting technology for Nomex honeycomb composite materials is still in the initial stage,not yet mature,especially the aspect of the acoustic system.In order to improve the processing quality and processing efficiency of Nomex honeycomb composite materials,the ultrasonic acoustic system should be studied.In this paper,the ultrasonic disc ultrasonic cutting acoustic system is taken as the research object,to study the tool load,force load and cutting temperature on its impact.The main research contents and achievements are as follows:(1)In order to ensure that the acoustic system can work stably when the tool load changes,so the geometric parameters of the tool load are studied,to study the influence of the disc cutter geometric parameters(thickness,wedge angle and diameter)of the ultrasonic cutting disc on the acoustic resonance frequency and the amplitude.Firstly,the vibration mode of the disc cutter is determined by the graphite powder vibration experiment;secondly,the thickness of the disc cutter,the wedge Angle and diameter of the resonant frequency and the amplitude of acoustic system influence are studied through the simulation and experiment;thirdly,use taguchi method to analyze the disc cutter geometry parameters influence on the resonant frequency and the amplitude of the primary and secondary relations.Finally,through the data analysis,it is found that the geometric parameters of the disc cutter have a linear relationship with the resonance frequency,which provides theoretical guidance for the design of the disc cutter.(2)In order to study the influence of force loading on the ultrasonic acoustic system,the problems of amplitude reduction,poor cutting quality and even stoppage of vibration caused by ultrasonic cutting force load are studied.Firstly,the cutting force model of the disc cutter is established according to the ultrasonic cutting motion equation.Then,the cutting force under different cutting parameters is obtained by ultrasonic cutting experiment,the approximate range of cutting force is determined,and then force load impact on acoustic system experiment,using the push pull gauge on the disc cutter force in this range,study on force load effect on the acoustic parameters,get the force load and the resonant frequency and the amplitude of the trend,which can provide theoretical reference for the actual processing technology.(3)The long time continuous cutting of the Nomex honeycomb composites will cause the system temperature to rise,resulting in the acoustic system to be not resonant,and the processing quality will become worse.Therefore,the influence of temperature on resonance frequency and amplitude of ultrasonic cutting acoustic system is studied.Firstly,the causes of ultrasonic cutting heat are analyzed.Then,according to the knowledge of mechanics and frequency equation,the theoretical model of temperature and ultrasonic vibration of disc cutter is obtained.According to the displacement equation of disc cutter,the theoretical model of temperature and ultrasonic cutting of disc cutter amplitude is obtained.Finally,the influence of temperature on the resonant frequency and amplitude of acoustic system is studied experimentally.The results of the study and the experimental results are consistent with the theoretical results and provide support for improving the efficiency of continuous ultrasonic cutting.