RESEARCH ON AUTOMOTIVE BRAKE DISCS OF SiC_P/Al COMPOSITE

The SiC_P/Al composite brake disc designed for the front brake of SANTANA cars was prepared by semi-solid stirring melting and liquid forging. The tensile properties and microstructures of the disc materials were examined, and the tribological-wear performances of the disc were tested on the SCHENCK brake testing system made in Germany. The results show that the tensile properties of the composites are superior to those of the conventional disc material, grey cast iron; and that under different braking conditions, the friction coefficients of the composite disc against the conventional brake pad are within the range specified by the standard of VOLKSWAGEN company and with small fluctuations. It is also found that the brake disc made of the composite has such advantages as light weight, high wear resistance, low braking noise and low braking temperature rises, smooth operating, etc. Hence, it is hopeful to substitute the composite disc for the traditional cast iron disc to increase reliability and to prolong the survice life of the car brake, to lighten the weight of the hanging system, and thus, to decrease gas expenditure of cars.