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The work aimed to determine the influence of iron-nickel alloy on the SPS sintering process of the TiB2-TiC-SiC composite. Composite casts were prepared with and without the additive of iron-nickel alloy to lower the sintering temperature. Composites were obtained by different methods. Samples were sintered directly from compounds and by a combined method where synthesis and sintering were conducted at the same time during SPS. The structure and properties of the composites were studied and compared. The addition of iron-nickel alloy allows sintering composites at lower temperatures, in addition, it reduces the porosity of the composite as iron-nickel alloy grains are placed between the composite grains and fill the gaps between the matrix polycrystals. Attention to ceramic matrix composite of the TiB2-TiC-SiC type is since they are characterized by a high melting point, high toughness, and high corrosion resistance. Above mentioned matrix was obtained at the temperature-1550°C by the SPS method. The addition of the iron-nickel alloy lowered it to 1200°C.

The paper presents a low-temperature method for the synthesis of tungsten boride containing ultra-fine powders of boron carbide matrix ceramics constituting an important class of superhard materials with diversity of industrial applications. Wet chemical method was used to prepare preceramic precursors. The technique provides annealing of a viscous paste of the mixture of ammonium paratungstate–zirconium(IV) oxide–cobalt acetate tetrahydrate–sucrose–amorphous boron at 200 °C in air and then at 600 °C in argon atmosphere for 2 h with the further grinding and additional annealing of the obtained powders at 800–1500 °C. Hot pressing of the complex ceramic powders at 1000–1700 °C was realized by using the SPS method. It was established that at 600 °C there were formed WO3–x, Co3O4, CoO, and amorphous carbon. The XRD data confirmed low temperature (800–1000 °C) formation of WC–Co, ZrB2, B4C, and W2B5. Tungsten carbide was completely converted into tungsten boride. Structural-morphological characteristics of the obtained samples were studied by using the SEM.