Features of Molding and Structure of Composite Materials Based on TiB/Ti, Obtained by Free SHS Compression Method

The work presents the thermodynamic calculations of the adiabatic combustion temperature and the fraction of the liquid titanium phase during the chemical reaction of the initial titanium and boron powders with the initial titanium content from 5 to 80 wt. % during the synthesis of materials based on TiB-Ti. It is shown that with an increase in the preheating temperature of the initial samples to 500 °C, the combustion temperature of the selected composition increases from 3200 to 3600 K, and the fraction of the liquid phase increases from 40 to 80 %. The peculiarity of molding composite materials based on TiB-Ti under conditions combining self-propagating high-temperature synthesis (SHS) and high-temperature shear deformation is studied. These conditions are realized in the method of free SHS compression, which allows synthesizing, molding and obtaining compact material in tens of seconds without using special molds. It was found that the maximum degree of deformation of the synthesized material corresponds to 20-40 wt. % free titanium. For the selected compositions, compact composite materials were obtained by free SHS compression method, the structural features were studied, and the density and porosity of the central and regional parts of the samples were measured.