Surface morphology and photoluminescence (PL) properties of both microcrystalline cellulose (MCC), microcrystalline powders of the alkali metals nitrites MNO2 (M = Na. K, Cs) (MCN) and two-component composite materials based on the MCC and MCN have been studied and characterized by means of optical microscopy and luminescence spectroscopy.

TiB 2 -SiC-C and TiB 2 -TiC-C heteromodulus ceramics were sintered by reactive hot pressing of TiC-B 4 C-Si and TiC-B 4 C precursors at 1830 °C and 30MPa. Sintering time at the maximum temperature was between 2 and 8 min. The reactions in TiC-B 4 C-Si green body create submicron (100 -400nm) TiB 2 crystals inside silicon carbide grains as well as B x Si y C z nanofibers, which nucleate near SiC surfaces. Low hardness graphite platelets are formed within the hard matrix during the in-situ exothermic reaction. "Soft-hard" grain combination produces substantially improved fracture toughness (up to 9MPa•m 1/2 ). The materials also demonstrate high thermal conductivity (up to 120W/m•K) and high thermal shock resistance. The thermal shock crack growth is arrested by the graphite platelets.

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