Investigation of the Impact of Groove Angle on the Fatigue Life of Grooved Brake Discs

The purpose of this study is to explore the effect of groove angle on the fatigue life of high-speed train brake discs. A thermal-mechanical coupling model of high-speed train brake discs with different angles (0°, 22.5°, 45°, 67.5°, and 90°) was designed and established. The effects of different groove angles on temperature and stress were studied and analyzed. Experimental specimens were prepared using special processing methods, and friction and wear characteristics experiments were carried out to further verify the simulation results. At the same time, based on the above results, life models of brake discs with different groove angles were established to study the effect of the angle on their fatigue life. Stress has a direct impact on the crack initiation life of groove brake discs, and temperature changes affect the material properties of brake discs, thereby affecting the crack initiation time. The crack growth life of 0° groove brake discs is longer, while the crack growth life of brake discs with other groove angles decreases as the groove angle decreases. Compared with the 0° groove angle, the crack propagation life of the 45° groove angle accounts for approximately 84.7%, while that of the 22.5° groove angle accounts for approximately 80.4%. These research results provide a theoretical basis and numerical research methods for the design of brake disc structures.