1093 / 2023-03-01 19:17:05

The friction-wear properties of copper-based friction discs enhanced by silicon carbide nanoparticles under different clutch conditions

To study the influence of nano-additives on the friction-wear characteristics of friction materials, the nano-sized silicon carbide particles are considered to add in composite to form the modified friction material. The influence of the silicon carbide nanoparticles (SCN) on the friction-wear characteristics of copper-based friction materials (CBFM) is investigated via the SAE-Ⅱ clutch bench with the applied pressure, rotating speed, and automatic transmission fluid (ATF) temperature taken into account. Moreover, the variations of friction torque and temperature are considered to evaluate the friction performance, and the variable coefficient is employed to describe the friction stability. The wear characteristics of friction materials are investigated by the disc changes in thickness and micro-morphology. The results show that the CBFM enhanced by SCN can provide a higher friction torque, which increased by 30% to 50% compared with CBFM. The variable coefficient of CBFM enhanced by SCN changes from 674 to 52 with the rotating speed raised from 600rpm to 3000rpm, which shows that the friction stability is relatively worse. Furthermore, the micro-morphology shows that the CBFM enhanced by SCN has lower porosity and surface roughness, which increases the microscopic contact area and the coefficient of friction (COF). Simultaneously, the reduction in porosity also leads to a decrease in the cooling quality, bringing about a rapid temperature rise. Thus, the wear amount of CBFM enhanced by SCN increases significantly, especially for the friction disc in the middle axial position.