writer：Han T, Wang H, Jin X, Yang J, Lei Y, Yang F, Yang X, Tao Z, Guo Q, Liu L
keywords：cement, composite,carbon fibers
source：期刊
specific source：J Mater Sci, 2015, 50(5): 2038-2048.
Issue time：2014年

A novel multiscale reinforcement was prepared
by the fast growth of carbon nanospheres (CNSs) onto the
surface of carbon ?ber (CF) under mildly hydrothermal
reaction. The uniform layer of CNS with an average
diameter of 85 nm produced on the ?ber surface. Further,
the structural analysis, surface morphology, and thermal
decomposition behavior of CNS–CF reinforcement were
studied by X-ray diffraction (XRD), scanning electron
microscope (SEM), X-ray photoelectron spectroscopy
combined with Fourier transform infrared spectroscopy and
thermogravimetric analysis, respectively. Cement-based
composites based on the multiscale CNS–CF reinforcement
have been fabricated to evaluate their high-temperature
resistance. CNS–CF/cement composites have a better
resistance to the degradation resulted from exposure to
elevated temperature up to 600 ° C than CF/cement com-
posites and pristine hardened pastes, since their relative
residual compressive strength is superior. The degrading
mechanisms due to exposure to elevated temperatures were
discussed and con?rmed by using SEM and XRD. Results
indicated that enhanced high-temperature resistance was
attributed to the effective interlocking between CF and
matrix due to (1) the presence of nanoscale CNS on the
surface of CF and (2) the formation of microchannels in the
matrix since CNS collapsed prior to CF after exposure to
elevated temperatures.