Effect of the perforated structure of friction block on the tribological behavior of a high-speed train brake interface in sandy environments

Abstract

The structural characteristics of friction blocks significantly impact braking performance, with perforated designs being favored for their superior heat dissipation capabilities. However, the influence of perforated friction block structures on high-speed train brake interfaces, especially in challenging environments, remains unclear. In this study, two customized friction blocks were examined using a self-designed sand-feeding device to assess the impact of perforated structures. Emphasis was placed on wear behavior, interface temperature, as well as vibration and noise characteristics. Furthermore, the evolution of tribological behavior was analyzed at various experimental stages. The experimental results revealed that the friction block with a hole trapped numerous sand particles, with some actively participating in the friction process. This led to destructive wear on the block's surface and created uneven thermal distribution at the interface. In contrast, the unperforated block experienced relatively mild wear, nevertheless, severe wear was still observed on its contact plateaus, resulting in concentrated contact pressure on specific plateaus, and consequently, higher levels of vibration energy and sound pressure compared to the perforated block.