A comprehensive study of the structural–phase transformations and hydrogen desorption kinetics in the Mg₅₆Al₄₄ system was conducted using a multistage approach combining thermodynamic modeling CALPHAD, Thermo-Calc 2025a, mechanical synthesis (MS), spark plasma sintering (SPS), and subsequent dispersion treatment. Thermodynamic modeling revealed a stable existence region of the intermetallic compound Mg₁₇Al₁₂, exhibiting Cp-T anomalies at 303 and 351 °C that closely corresponded to the experimental DSC/TGA results. Microstructural analysis showed that varying the ball-to-powder ratio BPR 20:1 and BPR 30:1 determines the defect density, crystallite size 25–45 nm, and lattice strain 1.5–3.0 × 10⁻³, all of which directly influence the hydrogen desorption kinetics. For the samples synthesized at BPR 30:1, the onset temperature of hydrogen release decreased to 180–200 °C while maintaining a hydrogen storage capacity of 4.9 wt.%, accompanied by a reduction in the apparent activation energy of desorption from 92 to 74 kJ·mol⁻¹ according to the Kissinger method. The dispersion stage partially disrupted and redistributed the surface MgO layer, leading to a reduction in its overall contribution and improvement in structural homogeneity, rather than complete oxide removal. The combined MS-SPS-dispersion processing route enabled controlled nanostructure formation, reduced the hydrogen desorption temperature by approximately 100 °C compared to conventional MgH₂-based materials, and significantly enhanced the thermokinetic performance. These findings demonstrate that Mg-Al alloys are promising candidates for solid-state hydrogen storage systems with improved desorption kinetics and reduced activation barriers.

In this work, the results of the structural and phase state of LaNi₅-based alloys modified with Ti, Mn, and Co elements, obtained by mechanical alloying and subsequent spark plasma sintering, are presented. X-ray diffraction analysis was carried out to determine the phase composition, lattice parameters, microstrain, and average crystallite size, as well as to study the morphology and microstructure of the synthesized samples. It was established that the ball-to-powder ratio (BPR) and the milling speed affect the degree of intermetallic phase formation and the level of accumulated microstrains. The optimal mechanical alloying parameters make it possible to form the necessary precursor components for subsequent spark plasma sintering (SPS). It was determined that the SPS process effectively promotes the formation of intermetallic phases such as TiNi, LaNi₄Mn, LaNi₃Mn₂, and LaNi₄Co, ensuring high crystallinity and a reduction in defects accumulated during mechanical alloying. The morphology and microstructure of the samples with titanium, manganese, and cobalt additions showed that at the mechanical alloying stage, all systems are characterized by a dispersed and agglomerated structure, a wide particle size distribution, and a developed surface. After SPS, all series exhibited material consolidation and the formation of a dense matrix with distinct grain boundaries.

The study examines the formation of carbon coatings produced by plasma-enhanced chemical vapor deposition (PECVD) in the PM-6 system developed at the Laboratory of Hydrogen and Plasma Technologies of the Branch of the Institute of Atomic Energy of the National Nuclear Center of the Republic of Kazakhstan. For the first time, the PM-6 setup has been used to obtain carbon-based coatings. The influence of key technological parameters such as microwave discharge power, gas mixture composition, and silicon substrate temperature on the morphology, phase composition, and physicomechanical properties of the resulting coatings was investigated. The morphology and elemental composition of the coatings were analyzed using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), while the phase composition was determined by X-ray diffraction (XRD) and hardness was measured using the Vickers method. It was established that increasing the plasma discharge power to 1.1 kW and raising the silicon substrate temperature enhance the carbon content in the coating (up to 87,66±5,6 at.%) and improve deposition uniformity. X-ray diffraction analysis revealed the formation of thin carbon layers with a predominantly graphitic structure. Following deposition, the surface hardness reached 1137 HV, which is twice that of the initial silicon substrate (416 HV). These results demonstrate the feasibility of controlled synthesis of carbon coatings through optimization of PECVD process parameters.

Hydrogen is a promising source of energy, which requires the development of reliable and efficient methods of its storage. The most promising technology is the storage of hydrogen in intermetallic compounds. This method is one of the safest and allows you to store hydrogen with a higher volume density. In this work, the effect of titanium alloying on the phase and structural composition of LaNi ₅ -based alloys synthesized by mechanosynthesis and spark plasma sintering is studied. X-ray phase analysis revealed that LaNi ₅ is the main matrix phase, and TiNi intermetallic compound is also formed. The oxide phases La ₂ O ₃ and TiO ₂ , which arose as a result of local oxidation, were found in a number of samples. Optimal crystallinity and phase uniformity characteristics were found in the LNT-1 sample, which confirms the high efficiency of the selected processing conditions. The optimal conditions for obtaining an intermetallic compound based on LaNi ₅ doped with titanium are: The ratio of the mass of the balls to the mass of the powder (BPR) is 20:1 for a duration of 8 hours with a rotation speed of 350 rpm and IPS at a pressure of 2 MPa, a temperature of 1300 ℃ and a holding time of 5 minutes. The results obtained allow us to recommend this approach for creating materials with improved characteristics for solid-state hydrogen storage.