The performances of BMI nanocomposites filled with nanometer SiC

Nanocomposites of bismaleimide (BMI) with different proportions of nanometer SiC were prepared by a high shear dispersion process and casting method at elevated temperature. The mechanical and tribological properties of the nanocomposites were investigated. The bending strength and impact strength of the nanocomposite specimens were determined, and the sliding wear performance of the nanocomposites was investigated on an M-200 friction and wear tester. The dispersion of nanometre SiC was observed with a transmission electron microscope (TEM), while those of the worn surfaces and transfer films on the counterpart steel ring were observed with a scanning electron microscope (SEM). The experimental results indicate that the nanocomposites exhibited lower friction coefficient and wear loss as well as higher bending and impact strength than BMI resin under the same testing conditions. The lowest wear rate was obtained with the nanocomposite containing 6.0 wt % SiC, while the highest mechanical properties were obtained with the nanocomposite containing 2.0 wt % SiC. The wear mechanism of the nanocomposite is mainly adhesion wear, while that of pure BMI resin is mainly fatigue cracking with plastic deformation.