英语论文网

The results indicates that C/C-SiC composites possess excellent wet friction and wear properties, and its high and stable friction coefficient can be kept at different braking velocity and braking pressure. After 300 times friction test, the wear rate is zero.The copper-based powder metallurgy friction material as tank clutch as well as the wet friction properties was fabricated. The results show that it’s effective to improve the surface wet ability between the material and lubricating oil, and enhance the adhesive ability of the material surface by adding spherical graphite and short chopped carbon fiber. The friction coefficient of this material is 0.08-0.11, and its friction energy is 1.86 times and 1.55 times of service clutch materials. Its energy load is 6.7 times of standard request.The constant-velocity friction test between C/C-SiC composites and 30CrSiMoVA steel was conducted. The dry brake performances of two friction pairs of C/C-SiC composites, the friction pairs between C/C-SiC composites with C/C composites, 30CrSiMoVA steel and Fe-based powder metallurgy material were studied, respectively.A 3D cycle-symmetric finite element model was set up by ANSYS software, and the wet brake process of C/C-SiC composites was simulated. Finally, the temperature and the thermal stress changes of different positions with different time were described.