Effects of brake pressure and temperature on squeal noise

Brake squeal noise has been an important issue for the automotive industry. This phenomenon is related to the modal coupling of the rotor and the pads of a brake system. When a mode of the pad matches with a mode of the rotor, the system becomes unstable. The consequence is the generation of additional vibration energy that cannot be dissipated by the system. In this manner, a solution is to improve the damping capacity of the brake system. This is accomplished by use of metal and viscoelastic materials laminates, where some of the vibrational energy is dissipated by shearing or extending the viscoelastic layer. Since the dynamic behavior of brake systems is a function of frequency, temperature, and brake pressure (friction force), it is of utmost importance to verify the influence of such parameters in order to design and select a proper multilayer treatment. This work presents a procedure to verify the influence of these parameters in the coupling of rotor and pads modes. Different conditions of pressure and temperature are applied on a brake system and the dynamic of the system related to squeal noise is evaluated.