High performance composite of silicon carbide/bismaleimide

A high performance composite based on silicon carbide (SiC) and bismaleimide (BMI) modified by allyl novolak for grinding tools and wear-resistant parts was developed and characterized. The results showed that residual strength at 440 C for I h decreased to 64% of its original strength without heat treatment, and its thermooxidative stability was better than that of SiC/polyimide (PI) composite made in similar way. The amount of resin in the composite had obvious influence on its mechanical properties, and the bending strength of the composite increased with increasing BMI content. But excessive BMI content resulted in bubbling of the composite. When 13wt% BMI was employed, the best composite with the bending strength of 82AMPa was obtained. After heat treatment at 280 C for l h, the bending strength of the composite was increased by 34% because of further crosslinking of resin at a higher temperature. SEM microstructure of the composite had a good agreement with its mechanical property.