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Titanium diboride (TiB₂) is one of the candidate materials for high temperature structural applications and also for control rod elements in high temperature nuclear reactors. In this paper the nano-sized titanium diboride powders were synthesized through a borothermic reduction by using TTIP and B₄C as titanium and boron sources. Three different concentration of TTIP solutions were prepared: 0.033, 0.050 and 0.10 M. After heat treating of products between 900 to 1200°C, the scanning electron microscopy (SEM) images and X-ray diffraction patterns of powder indicated that by using the 0.10 M TTIP, the only product was TiB₂; otherwise the product was TiB₂-B₄C composite.

The effects of BN/Ti molar ratio on the self-propagating high-temperature synthesis (SHS) reaction behaviors and final products in the Ti-BN system were experimentally investigated. With an increase in the BN/Ti ratio, the combustion temperature and wave velocity first increase and then decrease with the maximum values displaying at BN/Ti=0.67. A substoichiometric TiN_1-x was obtained for BN/Ti<0.67, and a stoichiometric one was produced for BN/Ti=0.67. Moreover, the microstructure photographs of the products reveal that with the increase of the BN/Ti ratio, the grains of the ceramic phases tend to be finer.

The effect of Al content on the self-propagating high-temperature synthesis (SHS) reaction among Al, TiO₂ and B₂O₃ was experimentally investigated. The Al content plays an important role in controlling the reaction behaviors. With the increase in reactant Al, the maximum combustion temperature decreases, the propagating wave velocity first increases and then decreases, while the ignition delay time shows an opposite tendency. More importantly, the increase of the Al content in the reactants has an insignificant effect on the phase constitutions of the synthesized products but reduces the size of the synthesized TiB₂ particles.

TiB₂ films deposited using various deposition techniques are used to increase the wear lifetime of industrial components. The performance of TiB₂ films is dependent on the coating–substrate adhesion. In this study, the fatigue behavior of TiB₂ films was investigated using the multi-mode scratch method. Films of TiB₂ were deposited on silicon wafers and AISI M2 steel substrates at different frequencies by pulsed-dc closed field unbalanced magnetron sputtering (CFUBMS). The microstructures of the films were investigated using SEM techniques, and the hardness was measured using a microhardness tester. A multi-mode operation was used for sliding-fatigue, like multi-pass scratching in the same track at different fractions of critical load (bidirectional sliding) and a standard mode using progressive load operation. It was observed that the films deposited at low frequencies had higher adhesion strength and microhardness, and a denser microstructure.

Titanium diboride (TiB₂) has attracted great interests for its excellent mechanical properties, chemical resistance and good thermal and electrical conductivities. So it is widely applied as cutting tool composites, wear resistant parts, metal melting crucibles and electrode materials. This paper presents synthesis of nano titanium diboride powders via sol-gel method using a mixture of TTIP and B₄C as precursors. In the hydrolysis step, B₄C to TTIP molar ratio varied from 1.3 to 2.5. Solution samples stirred well and after aging and drying process, they were heat treated in an argon atmosphere. X-ray diffraction (XRD) patterns and Scanning electron microscopy (SEM) analysis showed that the percentage of synthesized TiB₂ increased gradually as the molar ratio of B₄C to TTIP reached to 2.3, afterward increasing the B₄C to TTIP molar ratio caused decreasing of titanium diboride percentage.