Abstract:
The rare earth CeO
2 (1.0%, 1.5%, 2.0%) and Y
2O
3 (1.0%, 1.5%, 2.0%) mixed Nano-SiO
2 (2.0%, 3.0%, 4.0%) with different mass fraction modified phenolic resin-based friction material was prepared. The formula was designed through orthogonal tests, and the effects of the modified material on mechanical properties and friction and wear properties were studied by combining range analysis. The optimal addition was obtained. The wear mechanism of modified friction material was analyzed. The results show that the rare earth CeO
2 and Y
2O
3 mixed Nano-SiO
2 modification significantly improved the mechanical properties and friction and wear properties of the friction materials. The Rockwell hardness of the rare earth CeO
2 and Y
2O
3 mixed Nano-SiO
2 modified friction material was 62–78 HRL, and the shear strength was 31.4–34.5 MPa. The optimal mass fraction of CeO
2, Y
2O
3 and Nano-SiO
2 was 2.0%, 2.0% and 3.0%, respectively. In this case, the wear rate of the sample at the medium temperature stage (200–250 ℃) was small and stable, the friction coefficient and hardness was large, and the shear strength reached maximum. Under the optimal addition, the packing structure in sample was evenly distributed, small in size, and firmly bonded with the resin matrix. The graphite formed a continuous friction platform. The shear section presented an irregular tearing shape, and there were many smooth areas in the wear surface, without obvious soratches and grooves. The wear mechanism of the modified friction material at the medium temperature stage was mainly thermal fatigue wear and abrasive wear.