Characterization and experiments on the friction catastrophe behaviors of brake material during emergency braking

• Friction Catastrophe (FC) was characterized by intensity, duration and starting time.
• Influences of initial braking velocity and braking pressure on FC were investigated.
• The influence of initial braking velocity on the FC starting time is more obvious.
• The braking pressure affects the FC intensity more intensely.
• The results provide a theoretical basis for reducing frictional failure of brakes.

Based on previous researches on the phenomena and mechanisms of Friction catastrophe (FC), the characterizing methods of the FC were established and the influences of braking conditions on the FC were investigated by experiments. It is found that the FC intensity, duration and starting time can be used for characterizing the FC, which reflects respectively the decreasing degree, velocity and critical time of the friction coefficient in FC. For short duration, the starting time is more practically valuable. With the increasing of initial braking velocity or braking pressure, the FC starting time becomes shorter while the FC intensity grows bigger. By comparison, the influence of initial braking velocity on the FC starting time is more obvious while the braking pressure affects the FC intensity more intensely. It is believed that the results must be valuable for further studies on the FC and can also provide a theoretical basis for reducing the occurrence of frictional failure of friction brakes.