The features of combustion and structure formation of ceramic materials in the TiC-Ti3POx-CaO system

The results of a study focused on combustion synthesis of the biocompatible ceramic material TiC-Ti3POx-CaO is reported. The effect of tricalcium phosphate (TCP) additives on the combustion process of the (100% - X)(Ti 0.5C) d-X% Ca-3(PO4)(2) mixture, and the phase and structure formation of synthesis products, was studied. Parallel chemical reactions between Ti and C and between Ti and Ca-3(PO4)(2) occur in the combustion wave. It was shown that the resulting melt is based on titanium, and TCP forms the reactionary surface by capillary spreading onto the carbon black surface. The SHS product consists of an interconnected skeleton of nonstoichiometric titanium carbide grains with the titanium phosphate (Ti3POx) phase distributed uniformly along the grain boundaries, with inclusions of calcium oxide (CaO). The presence of the CaTiO3 phase is indicative of the interaction between calcium oxide and unreacted titanium in the post-reaction zone. Dense ceramic materials consisting of round-shaped grains of nonstoichiometric titanium carbide TiC0.55-TiC0.6, titanium phosphate (Ti3POx) and calcium oxide (CaO) were produced using the forced SHS- pressing technology. Increasing the TCP concentration reduces the size and hardness, but increases the residual porosity of structural components. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.