Synthesis of titanium carbide and titanium diboride for metal processing and ceramics production

OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 23 No. 4 2021 Ta b l e 2 Results of samples 2-1 and 2-2 determined by X-ray fl uorescence analysis Sample Content, wt.% Ti Impurities ≤ F * 2-1 68.28 0.57 1.15 2-2 68.36 0.48 1.16  The total content of elements with atomic mass less than that of fl uorine inclusive Ta b l e 3 Results of analysis of titanium diboride samples determined by inductively coupled plasma atomic emission spectrometry Sample Content, wt.% Ti В t otal Impurities 2-1 67.33 31.42 0.91 2-2 67.36 31.22 0.86 of atomic emission spectroscopy-inductively coupled plasma ( AES-ICP ). The results are presented in Table 3. Calculated content of titanium in titanium diboride amounts to 68.57 wt.%, and boron content is 31.43 wt.%. It should be noted that the data obtained on basic elements (Ti and B ) are comparable and close to the calculated content in spite of the fact that they are received by two absolutely different analysis tech- niques. It can also be argued that an increase in the duration of heat treatment of the charge from 20 to 30 minutes has practically no effect on the phase and elemental composition of the synthesis products. Taking into account the presence of impurities of reagents in titanium diboride, the content of the basic substance in it can be estimated at 97.5 wt.%. The optimal synthesis conditions in this case are: stoichiometric mass ratio of reagents to titanium diboride and a temperature of 1,600…1,700 °C. SEM images of the samples are given in Fig. 4. The images were obtained upon the reaction of titanium dioxide with carbon and boron carbide at 1,700 о С , and synthesis time interval – 20 and 30 minutes. Samples 2-3 and 2-4 are mostly composed of uniform particles. It appears to be an indirect proof of the carbide formation completion. The particles are in the shape of columns, and their boundaries are even. a b Fig. 4. SEM images of samples 2-3 ( a ) and 2-4 ( b )