Vladislav Grass

Effect of chemical modification conditions on the sintering behavior of TiC powders

Dense ceramics have been produced from a chemically modified titanium carbide powder. Chemical modification was carried out by siliciding titanium carbide powder in a gaseous SiO atmosphere at 1350°C. This treatment produced a Ti3SiC2 layer (up to 19 wt %) on the surface of the TiC particles. Hot pressing at a temperature of 1600°C and pressures from 10 to 20 MPa ensured effective densification of the modified powders. The density of the resultant material reaches 4.8 g/cm3, with a residual porosity under 2%. Its bending strength and fracture toughness are 330 ± 50 MPa and 6.2 ± 0.6 MPa m1/2, respectively.

Optimization of the Carbosilicothermic Synthesis of the Ti4SiC3 MAX Phase

We have studied the formation of the Ti4SiC3 MAX phase during the vacuum carbosilicothermic reduction of TiO2 with a combined reducing agent consisting of SiC and elemental Si and analyzed the effects of the synthesis temperature, heat treatment time, and percentage of elemental silicon in the starting mixture on the Ti4SiC3 yield. Optimal Ti4SiC3 synthesis conditions are as follows: temperature from 1550 to 1650°C, isothermal holding time of 360 min, and the starting-mixture composition TiO2 + 1.2SiC + 0.6Si. The Ti4SiC3 yield then reaches 92 wt %.

Production of Ti3SiC2-based materials by SHS forced compaction of layered composite Ti–SiC

A new method of synthesizing ceramic composite materials based on Ti3SiC2 using non-powder reaction compositions of titanium and silicon carbide was developed. Aceramic composite with a Ti3SiC2–TiSi2 matrix reinforced with SiC particles was obtained by SHS forced compaction of a multilayer packet of regularly packed layers of titanium foil and polymer film filled with silicon carbide particles. The particulars of the phase composition and microstructure of the material obtained were investigated.

High-temperature carbidization of carboniferous rocks

Processes of thermal metamorphism of carboniferous rocks have been studied experimentally. The conditions of high-temperature interaction of shungite carbon with components of the contained rocks, leading to formation of carbide compounds, have been determined. The results of this investigation contribute to the works on searching for new raw material for prospective material production.