Abstract:The material parameters of pad have important effects on the tribological properties of the friction pairs and the brake disc temperature distribution. Based on ADINA software, a 3D thermo-mechanical coupling model for brake disc and pad was established. The effect of thermal expansion coefficient, elastic modulus and thermal conductivity of pad material on brake disc temperature distribution and contact pressure at the interface was investigated under the brake conditions that the initial velocity was 100 km/h, brake pressure was 0.538 MPa and the inertia was 23 kg·m². The results show that when the thermal expansion coefficient of the pad increases from 0.5×10^-5 K^-1 to 2.5×10^-5 K^-1, the disc peak temperature rises by 8.4%, the maximum contact pressure increases by 47% at the same time. With the increase of the thermal expansion coefficient, the contact pressure distribution becomes more uneven, which makes the disc temperature change significantly. The elastic modulus increases by 9 times, the distribution of contact pressure is not sensitive to the elastic modulus of pad material, and the elastic modulus has little influence on the temperature of brake disc. The thermal conductivity increases by 7 times, the peak temperature can be reduced by 4.3%, the increase of thermal conductivity promotes the heat diffusion rate, which can reduce the disc peak temperature. The research results can provide references for the development of high-speed train pad materials.

Key words: disc brake; temperature field; contact pressure; thermo-mechanical coupling