Based on the data of synchrotron and electron microscopic studies of deformed and annealed Russian zirconium alloys, the possibility of analyzing the structural-phase state and crystallographic texture of individual phases has been demonstrated. A qualitative and quantitative phase analysis of deformed and annealed tubes made of Zr-Nb-(Sn-Fe-O) alloys was carried out using diffraction patterns obtained with synchrotron radiation. The main α-Zr phase and the following additional phases: β-Nb, β-Zr, and the Laves phase (intermetallic compound Zr(Nb,${\mathrm{Fe})}_2$), were found in the alloys. According to the results of texture analysis of all phases present in the alloy, the mechanisms of plastic deformation, recrystallization, and phase transformations of the main and additional phases were established. It is shown that during plastic deformation of the Zr-1%Nb alloy, a dynamic phase transformation β-Nb→α-Zr→β-Zr is observed. It is established that during recrystallization, larger grains of α-Zr are misoriented relative to the deformed matrix by rotating the prismatic axes around the basal axes by 30°, while fine grains are improved by polygonization and maintain the orientation of the deformed matrix. Processes for changing the orientation of grains of additional phases as a result of high-temperature annealing are also considered.

We have developed a technological process for obtaining compacted multi-graphene structures (CMGSs) with the thermal conductivity of 500 W/(m×K). We propose the “Soft” regime of graphite intercalation procedure, which yields conglomerates with alternating stacks of five graphene layers, while the “Standard” regime is characterized by the formation of alternating stacks of three graphene layers. X-ray diffraction analysis and transmission electron microscopy studies of Soft and Standard CMGS have shown that the thermal conductivity of these materials is limited by defect density, size distribution, and misorientation of nanocrystallites. The effect of micro-deformations and residual macro-stresses on thermal conductivity of CMGS is discussed. The Soft method facilitated the formation of CMGSs with a less disrupted internal structure, characterized by increased nanocrystallites and reduced misorientation angles relative to the Standard approach, resulting in a 38% enhancement in thermal conductivity. A refined model is proposed that incorporates these key structural factors governing heat transport in CMGSs. The proposed method made possible the preparation of CMGS-based material with a thermal conductivity 25% higher and with a density five times lower than those of copper. Our findings demonstrate that precise regulation of the intermolecular explosion parameters enables the design of lightweight, flexible carbon-based materials with engineered thermal conductivity characteristics for advanced thermal-management applications.

Spheronized particles of natural graphite with different diameters were obtained using a centrifugal impact method. Particle shape evolution during spheronization was studied, focusing on how active surface area and substructural modifications affect lithium-ion intercalation efficiency. An average particle sizes up to 20 μm (roundness 0.9) yielded a discharge capacity of 330–340 mAh g ⁻¹ and a coulombic efficiency exceeding 90%, attributable to improved particle contact, a larger intercalation area, and reduced diffusion limitations. Further fragmentation of graphite to sizes below 5 μm compromises the mechanical integrity of the particles, alters intercalation kinetics, destabilizes charge–discharge cycling, and ultimately results in a decrease in coulombic efficiency. It is shown that the classifier performs not only particle size separation, but also promotes increased particle spheronization and an enhancement in specific surface area (SSA) at constant processing time. During mechanical treatment, SSA increases while the average nanocrystallite size decreases, allowing for the introduction of a generalized parameter—the specific number of graphene layers on the active surface area. This parameter exhibits a strong correlation with specific discharge capacity (R ² = 0.997) and enables prediction of anode material performance.

We report natural graphite-based multigraphene materials with thermal conductivity enhanced by 20% compared to our previously reported results. The influence of density on the thermal conductivity of these materials was examined. Increasing the density from 1.0 to 1.8 g cm−3 leads to a more than twofold enhancement in thermal conductivity, surpassing the 600 W m−1 K−1 threshold. This result is attributed to a reduction in crystallite misorientation angles to below 15° and a two-order-of-magnitude decrease in defect density from 2 × 10−2 % to 4 × 10−4 %. A multiscale thermal conductivity model for such multigraphene materials was developed, calibrated, and assessed using experimental x-ray diffraction data and electrical conductivity measurements.

The approach and the setup for high thermal conductivity material λ > 300 W × m−1 × K−1 measurement were developed. The method is based on the measurement of established temperature gradients and thermal flows, followed by hardware and software processing. The setup was tested on copper, aluminum, isotropic graphite, and multigraphene materials with different thermal conductivities. Heat distribution and loss computer modeling was done to improve the measurement accuracy. Raw experimental data of multigraphene material with λ ∼ 500 W × m−1 × K−1 thermal conductivity were established to be 2% overestimated due to heat losses. The designed device is shown to provide high thermal conductivity and reliable measurements, complementing the instrumental capabilities of the laser flash assay and HotDisc.

Modeling of pyrolytic carbon (PyC) coating on spheronized graphite particles was performed with the goal of developing a high-performance anode material for lithium-ion batteries. The model takes into account convective and radiative heat transfer, particle movement in a fluidized bed, benzene pyrolysis kinetics and carbon deposition in view of the adhesion coefficient. It has been shown that efficient benzene decomposition for PyC coating formation occurs at temperature of 1000 °C–1100 °C. A nitrogen pulse feed rate of 10 pulses min ⁻¹ maximizes particle concentration in the benzene active decomposition zone. A semi-empirical model predicting PyC coating thickness as a function of temperature and particle diameter was presented. The calculated layer thickness varies from 20 to 45 nm and is in good agreement with the experiment. The obtained anode material exhibits ⩽ 5% loss in specific discharge capacity at 2 C and recovers up to 99% capacity at 0.1 C.