Abstract:Three groups of paper-based wet friction materials enhanced by aramid pulp with different porosity were prepared. The porosity of the samples was determined by improved oil immersion method. The effects of porosity on compression recovery property, thermal conductivity, viscoelasticity, friction and wear performance of paper-based wet friction materials were investigated. The results showed that, with the increase of porosity, the compressibility increased, the recovery rate became lower, the thermal conductivity increased to 0.998 W/(m·K), and the loss factor tanδ also increased. As the porosity increased, the friction coefficient of the sample improved, but the stability of the friction coefficient decreased. Although the wear rate increased with the increase of porosity, the addition of aramid pulp resulted in a wear rate that was far lower than the national standard. When the porosity of sample was 41.92%, the compressibility was 17.50%, the recovery rate was 55.47%, the thermal conductivity coefficient was 0.565 W/(m·K), the dynamic and static friction coefficients were 0.125 and 0.135 respectively, and the wear rate was 1.23×10-8 cm3/J, and the friction process was also stable. In summary, the porosity of paper-based wet friction materials should be controlled at about 40% to achieve the optimal performance. |