Research on the Influence of Floating Brake Pad Structure on the Friction Interface Performance of Disk Brake

Abstract

The friction contact state of the brake friction interface of high-speed trains in the braking process affects the braking efficiency, which in turn affects the braking safety and the service life of the components. This article focuses on the heat and stress distribution at the friction interface under the action of a floating brake pad structure. A floating brake pad structure comprising two sets of spherical joint structure is introduced. The multibody structure and rigid–flexible coupling effects of the floating brake pad are considered. Furthermore, a full reproduction flexible thermomechanical coupling braking model in the floating brake pad structure is constructed. The accuracy of the model is validated by conducting tests on a 1:1-scale high-speed train brake test bench. The temperature and stress distribution of the fixed/floating brake pad structure at 80 km/h are studied accordingly. The results show that in accordance with the temperature outcomes derived from the simulation model, the observed temperature variations in the test results demonstrate an average error of 8.93%. The action of the floating brake pad resulted in a significant reduction of 36.99% in the maximum surface temperature of the brake pad, as well as a reduction of 30.91% in the maximum stress. The temperature of the brake disk surface is decreased by 32.01%, while the maximum stress experienced a decrease of 30.65%. The contact area of the friction interface is increased by 100%. The floating brake pad demonstrates a more uniform distribution and consistent gradient of temperature and stress across its friction interface in comparison to the fixed brake pad.