Study On Dynamic Characteristics And Structure Optimization Of Disc Brake Disc

With the rapid development of technology and economy,the total number of cars in our country has increased year by year.At the same time,the safety and comfort of vehicles are also receiving public attention.Disc brakes are installed on many types of vehicles because of their relatively superior performance.However,the vibrations generated during vehicle braking not only reduce ride comfort,but can also lead to resonance of brake system components,which can lead to dangerous traffic accidents.Therefore,the study of the dynamics of automotive braking systems has important theoretical and practical significance for parking brake safety.Firstly,in order to study the non-linear dynamics of disc brakes during braking,a six-degree-of-freedom non-linear dynamics model is established and the kinetic equations are solved by the Runge-Kutta method using the Stribeck friction model and relevant parameters.The bifurcation diagram,Lyapunov diagram,time domain diagram,spectrum diagram and phase plane diagram of the brake pad and brake disc during friction braking were plotted,and the vibration characteristics of both under different braking pressure,braking speed,brake pad support stiffness and brake disc support stiffness were analysed.The results show that the braking pressure is an important factor in triggering the non-linear vibration;increasing the braking speed will increase the vibration amplitude,but will shorten the time to enter the steady motion state;increasing the supporting stiffness of brake pads and discs will reduce the vibration amplitude of the system.Then,the finite element model of the disc brake was established in Abaqus software,and the materials of the brake disc and the brake pads of three different materials were selected for thermal coupling analysis,and the temperature field cloud map and stress field cloud map of the brake disc under different braking pressure and different braking speed were drawn.The results show that the temperature in the contact area of the friction sub is greater than that in the non-contact area,which makes the brake disc experience a temperature gradient,thermal deformation and thermal stress,affecting the stability of the braking system.The factors affecting the stability of the braking system are analysed and verified.Finally,the Abaqus software was used to optimise the topology of the brake disc,and a comparative analysis of the modal,temperature and stress fields of the disc before and after optimisation was carried out to verify the rationality of the optimisation,and to provide an idea for the structural design of disc brakes.