Research On Surface Residual Stress Of Cylindrical Vibrating Gyroscope

Cylindrical vibrating gyroscope is a new type of metal vibratory gyroscope developed in recent years.Due to its features of simple structure,low manufacturing cost and high accuracy,it has a broad application prospect in the fields of aerospace and weapon equipment.The core component of the cylindrical vibrating gyroscope is cylindrical resonator,which is a kind of high precision thin wall cylindrical structure,which is formed by precision turning.Because of the extrusion and friction on the machined surface of the cutter and the cylindrical resonator,the surface of the cylindrical resonator generates the residual stress.At present,many researches on the manufacture,modification,control and error analysis of cylindrical resonator are carried out at home and abroad,but little research has been done on the residual stress in the manufacture of cylindrical resonators.For this reason,this dissertation explores the formation mechanism,influencing factors and distribution law of the surface residual stress of cylindrical vibrating gyroscope,and proposes a specific method to eliminate the surface residual stress of cylindrical resonator.The main contents of this dissertation are as follows:1.The formation mechanism of the surface residual stress of cylindrical vibrating gyroscope is analyzed,and the effect of turning on the surface residual stress of cylindrical resonator is analyzed in detail.The effect of processing parameters on the surface residual stress of cylindrical resonator is investigated by simulations and experiments.2.The turning simulation model of cylindrical resonator is established,and the distribution law of surface residual stress of cylindrical resonator is analyzed by simulation.The variation law of the thickness of residual stress with machining parameters and the magnitude and distribution of axial residual stress and tangential residual stress on the surface of cylindrical resonator are obtained.3.Step mask corrosion,as a measurement method of stress,is proposed to measure the surface residual stress of cylindrical resonator.The principle and procedure of the step mask corrosion method are expounded.The method can efficiently analyze the surface residual stress layer of the cylindrical resonator layer by layer and then accurately measure the variation of residual stress in different orientations and depths by using X-ray diffraction method.4.An complex method based on chemical etching and electrolytic polishing is proposed to remove the surface residual stress of the cylindrical resonator.The principle and specific steps of removing surface residual stress are introduced in detail.the surface residual stress can be reduced from over 400 MPa to about 50 MPa by experiments.Finally,the variation of the important parameters such as frequency cracking and quality factor of the cylindrical resonator before and after the residual stress removal is compared by experimental analysis.