The Process Factors Research On Synthesis Of TiN By Carbonthermal Reduction And Nitridation Of TiO₂

TiN is a new type of functional ceramic material, in recent years due to its many excellent physical and chemical properties, are widely used as additives for preparing high-performance composite material. Based on the analysis of the existing TiN powder preparation methods, on the basis of using titanium pigment, carbon black as raw materials we studied the feeding quantity influence on the synthetic TiN powder which prepared by carbon thermal reduction nitridation of TiO2.The thermodynamic analysis showed that:the beginning of the reaction temperature of TiO2carbonthermal reduction and nitridation preparation TiN powder relate to the temperature、CO and N2partial pressure in the furnace. Increase the N2partial pressure in the furnace, lower CO partial pressure, can make response to temperature lowering. The order of the phase evolution:TiO2�'TinO2n-1(n>5)�'Ti5O9�'Ti3O5�'TiN.The sample size, the flow rate of N2and other technological factors on the rate of TiO2carbothermal reduction and nitridation synthesis of TiN was analyzed by the continuous all-isothermal thermogravimetric method, XRD, SEM and TEM. The results showed that:With the reduce of the samples’quantity in the furnace, the sample complete reaction time was reduced and the synthetic rate was increased; Reduced the sample size, it is possible to improve the reaction rate, but have little effect of the rate of synthesized TiN; Reduction in the number of feeding can improve purity of synthetic product and reduce the impurity content in the product. Increase the quantity of sample, the Ti(C, N) phase will appear in the product, the content of Ti(C, N) phase increased with CO partial pressure increases.