Material-Combined Vehicle Brake Disc Design for Enhanced Cooling Performance

The improvement of heat dissipation performance of ventilated brake discs is vital of braking safety. The usual technical approaches shall be material optimization or structural improvement. In this paper, a simulation model of the heat transfer of brake discs is established using STAR-CCM+ software. Cast iron, aluminum metal matrix composite (Al-MMC) and carbon-ceramic composite materials (C-SiC) are compared. The results show that: Al-MMC have better thermal conductivity so that a more uniform temperature gradient distribution shall be formed; C-SiC have poorer heat capacity yet better thermal stability; cast iron performs better with convective heat transfer rate, which enhances the heat transfer between the surface and surrounding flow field. Based on the results, this paper proposes four types of material combined brake disc using different friction materials and geometry structures. At the level of material application, Al-MMC and C-SiC friction layer are compared. At the level of geometric structure, 3mm and 5mm are chosen to be the thickness and the different results of simulation are discussed. For material selection, the material-combined discs have lower friction surface temperatures compared to the use of single materials, and the overall temperature gradient distribution is more uniform; for the selection of the friction layer thickness, the use of the 3mm composite friction layer scheme, regardless of the Al-MMC or C-SiC, has a lower friction surface temperature than the 5mm friction layer scheme. For different friction layer thickness, using 3mm friction layer have lower friction surface temperature than 5mm regardless of the materials, and the temperature distribution is more uniform. However, due to the increased cast iron content, the 3mm solution is less lightweight than the 5mm solution. Overall, the material combination approaches can offer a significant performance improvement over the single material discs, which contributes to the safety of automotive braking.