Effects of Sintering Temperature on Bending Property of C<sub>f</sub>/SiC Brake Material

Abstract

With increasing of the speed of the train, the requirement of the performance of the braking friction materials is more and more higher. It is urgent to find new braking materials to satisfy the rigorous using environment. Cf/SiC has the broad application prospects when it is used as a new kind of braking material. On this article, in order to shorten preparation cycle and reduced production costs, short carbon fiber is substituted continuous carbon fiber felt. Cf/SiC brake materials were prepared by the way of molding compression-pressureless sintering with resin binder at 1800°C, 1850°C and 1900°C, respectively. The effect of sintering temperature on bending property of brake material was researched. The experimental results show that with the increase of sintering temperature, the bending strength of Cf/SiC brake materials rose first and then fell. If sintering temperature is too high, which will lead the crystal grain to grow up and the crack is easy to produce. Finally make the bending strength of composites reduced. When sintering at 1850°C, the bending strength of the specimen reached maximum. At the same experimental condition, the bending strength of Cf/SiC brake material sintered at 1850°C is 18.81MPa, compared to the sample sintered at 1800°C and 1900°C, the bending strength of the specimen is increased 14.56% and 5.26%, respectively. The toughening mechanism of carbon fiber debonding and fiber pull were generated in the process of bending fracture. The fracture model of composites is pseudo-ductile type.