Synthesis of titanium carbide from woody materials by self-propagating high temperature synthesis

摘要

Woody waste materials were used for the preparation of titanium carbide ceramics (TiC) by utilizing combustion synthesis or self-propagating high temperature synthesis (SHS).The outer and inner barks and wood of the sugi (Cryptomeria japonica) were used to react with titanium powder as rawmaterials,as well as commercially available reagents of cellulose and lignin.It was detected by X-ray diffractometry that the TiC phase was obtained directly arose from the mixture of the woody waste materials and titanium powder,without formation of anymajor oxide phase.Broadening of half width and shift in diffraction peaks of the obtained TiC phase suggest that the TiC phase included lattice deformation and had a non-stoichiometric composition.This latter observation may imply the release of carbon,i.e.,formation of carbon mono-or dioxide.The carbide phase had a meanparticle size of 1-5 mum,and showed a shape similar toa TiC synthesized from a mixture of graphite and titanium powders.The combustion velocity of the mixtures tended to increase with the relative amount of carbon included in the woody materials.On the other hand,the velocity indicated a tendency t decrease with hydrogen and oxygen contents in the materials,which resulted from an endothermic reaction,accompanied with pyrolysis of the woody waste materials during SHS reaction.