Vibration Friction And Thermal-structure Coupling Of Brake’s Rotating Joint Surface

High-speed spinning disk parts can be seen in various mechanical structures. The friction existed in the joint surface can cause the problem of vibration and noise. Then the contact condition may be worsened in this condition. In this case, the precision and life of the machine will reduce and even more accidents will occur if the mechanical structures failure. The dynamic characteristics of vibration friction of the rotary joint surface are studied in this paper. It not only can get further acknowledge about the essential of vibration friction but also provide basic theory for improve the reliability and life of the rotating parts.The braking system consists of disk and pad is taken as study object. This article studies the effect of the vibration friction on the stability and dynamic characteristics of the braking system during the braking. The effect of the joint surface parameters on the stability of braking system and the effect of the thermal-structure coupling on the disk vibration are mainly studied. Theory guidance is provided for choosing material and designing and optimizing the brake by the above study.The major research contents of this article are as follows:(1) Based on extensive literature review, this article sums up the current state and existing problem of vibration friction and thermal-structure of the disk study, and then provides the aim and significance of the study of combing the vibration friction and thermal vibration.(2) The vibration friction model and its dynamic equation are built in this paper. Then the effect of parameters of the braking system on the stability of the system is studied by the MATLAB/Simulink, and the methods improving the stability of the system are provided..(3) The finite element analysis model is built by ABAQUS, and the temperature, stress and disk vibration are analyzed by this model. The distribution and change characteristics of the temperature and stress are achieved. The reason of the thermal vibration and the instability of the disk during braking are analyzed, then the resonance frequency and the range of velocity and the time and velocity of instability of the disk during braking are achieved.(4) The prestress modal analysis of the disk is taken to compare with the result of the modal test. Then the natural frequency and vibrational modes of the disk are obtained.The study shows that:slip-stick vibration appears at low braking speed, the ill vibration can be reduced by improving the system damping or reducing the brake pressure and system stiffness; the distribution of temperature and stress of the brake system is not evenly; the disk and pad will be warped by the coupling effect of the temperature and stress, and it introduces the thermal vibration; the resonance phenomenon appears at the beginning of braking, the resonance frequency is 5500Hz compare to the modal analysis result.