The role of the damping component deformation in improving the tribological behavior at the high-speed train braking interface

Abstract

Aiming to the issue of the unclear mechanism and lack of design basis for the influence of the deformation of the damping component installed in the brake pads of high-speed train, various perforated configurations were implemented on the damping component to obtain different typical deformation. The damping component was then installed on the back of the friction block and the tests on friction braking were performed using a test rig designed to assess high-speed train braking performance. A finite element model (FEM) was established for wear simulation to obtain block worn surfaces that closely matched the test results, succeeded by conducting both complex eigenvalue analysis (CEA) and implicit dynamic analysis (IDA). The findings indicate that the perforated configurations effectively provided damping components with different deformation capabilities, and increasing the deformation weakened its damping effect on vibration. The damping component deformation not only significantly affected the non-uniform wear on the block surface but also altered the wear patterns. Inappropriate deformation exacerbated the degree of non-uniform wear, leading to complex abrasive wear and adhesive wear, and added to the interface damage. Therefore, the damping component deformation significantly altered the friction-induced vibration and noise (FIVN) characteristics. Enhancing the deformation disrupted the continuity of FIVN but intensified its strength. The major reason is that the damping component deformation determined the time length of its compression and rebound, and inappropriate deformation significantly amplifying the oscillation intensity of contact area and friction force. This posed a challenge in establishing stable contact at the braking interface, ultimately leading to the generation of intense FIVN. Installation of damping components in brake pad to improve interface contact characteristics and suppress FIVN should carefully consider the structural of the braking system, and design damping components with appropriate deformation. Otherwise, it may lead to opposite effects.