Investigation of thermo-structural behavior of disc brake

Abstract Over decades, disc brakes have gained popularity and have been progressively used across many vehicle types, from light motorbikes to huge road trucks and trains. A prolonged and repetitive braking may still induce brake fade, so compromising the efficacy of a disc brake due to alterations in friction characteristics resulting from elevated temperatures and overheating of brake components. Overheated components may result in further problem, including thermal cracks, plastic deformation, and a reduced lifespan of the disc brake. Therefore, accurately predicting the temperature rise in a disc brake system is of great importance in the early design stage. Yet, owing to the interactions of several physical phenomena, the evaluation of disc brake performance is highly complicated. This paper presents the thermal behavior of the solid and ventilated brake discs of the vehicles and a transient analysis for temperature evolution caused by mutual sliding of two members of the thermo-elastic disc brake system based on three-dimensional modelling techniques. A driving cycle of repeated braking process of three successive braking, in the form of saw tooth is taken to investigate the thermos-mechanical behavior of disc brake.Operation conditions, thermo-physical properties of materials and dimensions of the brake system were adopted from the real representation of the braking process of the railroad vehicle. We performed thermal and structural stress, deformation and temperature analyses on a ventilated disk brake as well as solid disc brake with numerical method. The stress analysis was used to determine the maximal von-Mises stress generation where the fatigue crack were simulated on a vented disc brake of a railroad vehicle. The result show that the highest temperature value at solid brake disc reaches to 291.14 °C, the temperature of inner edge reaches 73.13°C and that of ventilated disc brake was 260.12°C maximum temperature and 69.76°C minimum temperature. The corresponding effective stress distribution of the disc is calculated with maximum braking time becausethe thermal cycling stress is larger than the threshold stress.