Combustion synthesis of TiCx–TiB2 composites with hypoeutectic, eutectic and hypereutectic microstructures

An experimental study on self-propagating high-temperature synthesis in the Ta–B4C system

“…Due to high exothermicity of the reaction, formation of the TiB 2 -TiC composites has been extensively investigated by self-propagating high-temperature synthesis (SHS) from either Ti-B 4 C or Ti-B 4 C-C reaction systems [4][5][6][7][8][9]. Combustion synthe- * Corresponding author.…”

“…Almost all of the previous studies [4][5][6][7][8][9]13,14] associated with the reactions between B 4 C and transitional metals of groups IVB and VB considered formation of monocarbides and diborides. However, the Ta-B phase diagram shows five boride phases, TaB 2 , Ta 3 B 4 , TaB, Ta 3 B 2 , and Ta 2 B, among which TaB and TaB 2 are stable from the room temperature to their melting points [15][16][17].…”

Effect of TiO2 addition on the combustion synthesis in the Ti–B4C system

“…An appropriate amount of the TiO 2 addition could indeed decrease the reaction intensity and velocity, and thus favor the process control. 5,14 When the TiO 2 addition content is larger than ∼11 wt%, however, the eutectic-like microstructure disappears because the maximum combustion temperature is below the eutectic point of the TiC x -TiB 2 system, which is in the approximate range of 2663-2973 K for the stoichiometry of TiC x varying from 0.68 to 0.95, as reported by Ordanyan et al 15 The microstructure is characterized by numerous individual particulates consisting of hexagonal prism or rectangular shapes of TiB 2 and roundish shapes of TiC x [see Fig. When the addition content is no more than ∼22 wt%, the products consist of TiC x and TiB 2 diphase without any intermediate phase and remnant reactant in the scope of the XRD detection accuracy.…”

“…5,12 On the other hand, the formation of gaseous phases such as CO and BO may provide a more convenient route for mass transfer and thus, to a certain extent, favors the reaction completion. 7(c) and 8(c).…”

Effect of Ni content on microstructures and mechanical properties of hot-pressed TiC–TiB2–Ni composite

“…However, TiC-TiB 2 composites are very difficult to fabricate by conventional sintering methods due to their high melting points (3067°C and 2980°C, respectively) and low self-diffusion coefficients [13]. In recent years TiC-TiB 2 composites have attracted much attentions and many material reseachers tried to obtain low-cost and highperformance TiC-TiB 2 composite using various preparing methods [14][15][16][17][18][19][20]. Locci et al using Ti, B 4 C and C as raw materials obtained TiC-TiB 2 composite with a relative density of 98% at 1700°C by SPS method [21].…”