Contact behaviour and vibrational response of a high-speed train brake friction block

Brake experiments were conducted on a typical kind of friction blocks of a high-speed train. The friction and wear, interfacial temperature, vibration, and noise generated at or by the brake interface were investigated, and the interrelationship between the vibration response and the contact behaviour of interface was analysed. The results showed the friction coefficient, vibration energy, and noise intensity were lower when the block surface experiences less wear; the friction coefficient and contact angle of the block were important factors affecting the vibration characteristics of the brake system. Moreover, the contact inclination angle increased with the increase in the friction coefficient, and mode coupling of the brake system occurred; as a result, the vibration intensity increased, and squeal occurred. •The contact conditions and vibration characteristics were conducted by a series of brake tests.•A contact inclination angle between the block surface and the disc surface was observed.•The cause-effect correlations between contact behavior and vibrational response were discussed.•The contact inclination angle significantly influences on the stability of the brake system.