Influence of fiber content on C/C-SiC brake materials fabricated by compression molding and hot sintering

In this work, short carbon fibers were utilized as reinforcing materials to incorporate with C-SiC ceramics. C_f/C-SiC composites containing diverse fiber contents were fabricated by combining compression molding and hot sintering. Mechanical and tribological properties were carefully investigated. The result indicates that 30 vol% fiber content composite shows the highest flexural strength (201.42 MPa) and shear strength (116.68 MPa). The reinforcing mechanisms are summarized as fiber pulling-out, fiber debonding and fiber bridging, as well as crack deflection. Tribological testing reveals that 30% fiber content composite shows the strongest wear resistance (3.95 × 10⁻⁶ mm³/N⋅m) and cyclic performances (COF of 0.27 after 50 cycles). The friction mechanisms are divided into abrasive wear, adhesion wear and oxidation wear by different wear stages.