Tribological behavior of three-dimensional needled ceramic modified carbon/carbon composites in seawater conditions

Silicon carbide (SiC) or boron carbide (B4C) ceramic filler was introduced into a three-dimensional needled carbon fiber integrated felt by unidirectional pressure slurry infiltration-filtration to prepare ceramic modified carbon/carbon (C/C) composites. The contents of SiC and B4C introduced by a one-shot infiltration were about 18 wt% and 16 wt% respectively. The fade of coefficient of friction (COF) in seawater conditions for C/C composites was significantly reduced by ceramic modification. SiC modified C/C composite was superior to C/SiC for its excellent stable friction without any fade in seawater conditions. The weak hygroscopicity and the ability to produce fresh debris continuously in seawater conditions were the primary factors for ceramic modified C/C composites to reduce and even avoid the fade. The double lubrication action from water film and silicon oxide film increased the COF fade for C/SiC.