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Carbon fiber‐reinforced silicon carbide matrix composites (C/C‐SiC) have received considerable attentions because of their superior friction and wear behaviors. In this paper, C/C‐SiC composites were fabricated by the reaction melt infiltration method, and the braking performance, the microstructure of friction surface, and wear debris at different braking speeds were also investigated. The mean coefficient of friction increases to the maximum value of 0.52 at 10 m/s and then declines afterwards with an increase in the braking speed. The higher coefficient of friction at low braking speed indicates the excellent braking performance of the C/C‐SiC composites for low braking energy. Excellent wear resistance is demonstrated by the low wear rate of the C/C‐SiC composites in comparison with C/C composites.

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Silicon nitride foams were prepared by direct foaming and subsequent rapid sintering at 1600 °C. The intense thermal radiation generated under the pressureless spark plasma sintering condition facilitated necking of Si3N4 grains. The prepared foams possessed a porosity of ∼80 vol% and a compressive strength of ∼10 MPa, which required only ∼30 min for the entire sintering processes. Rapid growth of one-dimensional SiC nanowires from the cell walls was also observed. Thermodynamic calculations indicated that the vapor–liquid–solid model is applicable to the formation of SiC nanowires under vacuum.

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