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In the presented research work, 3D materials were fabricated by additive moulding by means of extrusion of a mixture of high filled polymers and nanopowders of Ti-Al intermetallides with subsequent sintering at 1100 ± 20 °C, 1200 ± 20 °C and 1250 ± 20 °C (MEAM-HP process). Nanopowders of Ti-Al intermetallides were obtained by the electrical explosion of intertwined aluminium and titanium wires. It was found that the structure of the materials comprises an AlTi matrix with Ti2AlN MAX-phase particles distributed within it, surrounded by a composite layer of Ti3Al-Ti2AlN. Sintering temperature increases led to changes in the concentration of TiAl, Ti3Al and Ti2AlN phases in the samples. Besides that, aluminium oxide particles were discovered in the structure of the materials. It was found that as the sintering temperature was increased from 1100 ± 20 °C to 1250 ± 20 °C, the average microhardness of the samples increased from 193 to 690 HV0.1.

In this research, Ti–Al bimodal powders were produced by simultaneous electrical explosion of titanium and aluminum wires. The resulting powders were used to prepare powder–polymer feedstocks. Material characterization involving X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and melt flow index (MFI) determination were carried out to characterize bimodal powders obtained and evaluate the influence of the powder composition on the feedstock flowability. The bimodal distribution of particles in powders has been found to be achieved at a current density of 1.2 × 107 A/cm2 (the rate of energy input is 56.5 J/μs). An increase in the current density to 1.6 × 107 A/cm2 leads to a decrease in the content of micron particles and turning into a monomodal particle size distribution. The use of bimodal powders for powder–polymer feedstocks allows to achieve higher MFI values compared with monomodal powders. In addition, the use of electroexplosive synthesis of bimodal powders makes it possible to achieve a homogeneous distribution of micro- and nanoparticles in the feedstock.

In this research, Ti-Al powders were produced by electrical explosion of twisted titanium and aluminum wires. The resulting powders were pressed and sintered in a vacuum to obtain bulk composites. Transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD) studies were performed to analyze synthesized powders and bulk composites. The studies carried out showed the presence of α-Ti, α2-Ti3Al, and γ-TiAl phases, which are formed by coalescence of Ti and Al clusters formed in the process of non-synchronous electrical explosion of twisted wires. Furthermore, an increase in the energy injected into the wires leads to a decrease in the content of micron particles in the powder. During sintering of pressed Ti-Al powder in the range 800–1250 °C, phase transformations occur due to the diffusion of aluminum atoms towards Ti compounds. The research findings can be used to obtain Ti-Al particles and bulk composites with a controllable phase composition.