Mechanics Research Articles

Inducing piezoelectric behavior in a copper iodide cubane cluster-based metal-organic framework via linker engineering.

Cu4I4 cubane-type secondary building units are reticulated with a piperazine linker at room temperature to crystallize the metal-organic frameworks (MOFs) Cu4I4(Pip)2 in a non-centrosymmetric P6222 space group. For the first time, cubane cluster type MOF's strong piezoelectric nature has been studied by switching spectroscopy piezo force microscopy (SS-PFM) and piezo force microscopy (PFM) mapping of the crystal, with piezoelectric constant (d33) ∼52.33 pm V-1, highlighting its potential for mechanical energy harvesting processes.

Synthesis of Nanocrystal-Embedded Bulk Metallic Glass Composites by a Combination of Mechanical Alloying and Vacuum Hot Pressing

Bulk metallic glasses (i.e., BMGs) have attracted a lot of research and development interest due to their unique properties. Embedding BMG composites with nanocrystals can further extend their applications. In this study, Ta-nanocrystal-embedded metallic glass powder was prepared via the mechanical alloying of (Cu60Zr30Ti10)91Ta9 composition for 5 h using starting elemental powders. The structural evolution during the mechanical alloying process was examined using X-ray diffraction, scanning electron microscopy, synchrotron extended X-ray absorption fine structure, transmission electron microscopy, and differential scanning calorimetry. The 5 h as-milled powder was then consolidated into a bulk sample using vacuum hot pressing with an applied pressure of 0.72, 0.96, and 1.20 GPa. The effects of the applied pressure during vacuum hot pressing on the structure of the obtained BMG were investigated. The experimental results show that Ta-nanocrystal-embedded metallic glass composite powder was prepared successfully after 5 h of mechanical alloying. The 5 h as-milled composite powder exhibited a large supercooled region of 43 K between the glass transition temperature of 743 K and the crystallization temperature of 786 K. Using vacuum hot pressing at 753 K for 30 mins with an applied pressure, dense nanocrystal-embedded BMG composites were synthesized. The relative density and the crystallization temperature of the BMG composites increased with increasing applied pressure. The nanocrystal-embedded BMG composites prepared at 753 K for 30 mins with an applied pressure of 1.20 GPa exhibited a relative density of 98.3% and a crystallization temperature of 786 K. These nanocrystals were Ta, Cu51Zr14, and other possible Cu–Zr–Ti alloys (e.g., Cu10Zr7) that were randomly dispersed within the glassy matrix.

RESTORATION OF SURFACE PROPERTIES OF CONCRETE PAVEMENTS: OVERVIEW OF PRACTICES AND ASSESSMENT IN FRANCE

This article presents an overview of practices and assessment in France regarding the restoration of surface properties of concrete pavements, focusing on enhancing skid resistance, safety, and durability while minimizing environmental disturbances. The evolving priorities in highway pavement management underscore the importance of integrating aesthetic, urbanistic, and functional considerations, including stormwater management and noise reduction. The article outlines a new circular under preparation in France aimed at improving skid resistance through mechanical processes, emphasizing the qualitative aspects of pavement surface treatment over quantitative metrics. It discusses the significance of microtexture and macrotexture in achieving desirable skid resistance, detailing the specifications for aggregates to ensure durability and resistance to polishing. The article also highlights various surface treatment techniques, including surface dressings, sawn grooving, and peening, based on over 15 years of French experience. These techniques are evaluated for their effectiveness in restoring skid resistance on heavily trafficked pavements, with a special focus on transverse grooving and its impact on water drainage and pavement drying. The comprehensive approach to pavement restoration presented in this article reflects a broader commitment to road safety, environmental considerations, and the overall performance of highway networks. (Abstract generated by AI tool ChatGPT 4)

Aesthetic evaluation underpinning brand love relationship development: an activation likelihood estimation meta-analysis and multivariate analysis

ObjectivesBrand love is a crucial construct in marketing strategies. Building brand love can generate stable profits for enterprises. Although the marketing literature points out that aesthetic factors contribute to establishing the relationship as a trigger, to what stage of the relationship do they influence the minds of consumers? The present study attempts to reveal the involvement of aesthetic experiences in brand love developmental dynamics.MethodologyUsing the activation likelihood estimation method, we address this issue by assessing overlapping brain regions between brand love at each stage and aesthetic experiences. We adopted three major meta-analytic decoding analysis modules to objectively interpret these brain regions, namely, Neurosynth, NeuroQuery, and the Behavioral Analysis plugin (BrainMap platform). Moreover, we performed a correspondence analysis to identify relationships of mental processes between aesthetic experiences and brand love in each developmental stage of brand love.FindingsOur results suggest that the same neural mechanism and mental processes may be underlaid between brand love and aesthetic experiences across all stages. Although reward- and emotion-related mental processes are commonly underlaid between brand love at the first-half stage and aesthetic experiences, exteroceptive and interoceptive signals may drive those mental processes between the early and migration stages of brand love, respectively, and aesthetic experiences. Overlapping regions of brand love at the stable stage and aesthetic experiences may be associated with semantic processing.ConclusionWe demonstrate that several brain regions overlapped between brand love and aesthetic experiences across all the brand love developmental stages. Therefore, aesthetic experiences might be associated with the mental processes of brand love development through all the developmental stages. Our results suggest that aesthetic experiences are essential elements for developing brand-love relationships.ImplicationsOur findings indicate that marketers should recognize that aesthetic experiences play a crucial role in building a bond between brands and consumers, not only when choosing brands. Thus, marketers need to design visual strategies from the view of nurturing brand-love relationships.

Exploring the relationship of salivary pH and flow rate with tooth wear severity: A cross-sectional study

BackgroundTooth wear is the loss of dental hard tissue due to chemical and mechanical processes, and its prevalence ranges from 13 to 80% in the general population. Management depends on understanding potential risk factors; however, the role of saliva as one of them is not completely understood. The aim of this study was to explore the relationship between salivary pH and flow, and tooth wear in patients referred to a specialized dental clinic for tooth wear management. MethodologyData used in this study included stimulated (SWS) and unstimulated whole salivary (UWS) pH and flow rate. Dependent variables were the average occlusal Tooth Wear Index (TWI) and the average of the surfaces with the maximum Tooth Wear Evaluation System 2.0 score (TWES). Univariate and multivariate linear regression models were utilized, including a multivariate analysis without outliers. Sex and age were added as confounders. ResultsA total of 159 patients were included in this study. The average age of the individuals was 37.1 (± 9.1) years and 34 (21%) were female. Univariate models showed a statistically significant association between both TWI and SWS pH. Multivariate models showed that the negative associations between SWS (β = -0.20, C.I. = -0.36 – -0.03 [TWI]; β = -0.12, C.I. = -0.22 – -0.02 [TWES]) and UWS pH (β = -0.12, C.I. = -0.26 – 0.02 [TWI]; β = -0.09, C.I. = -0.18 – 0.00 [TWES]) and tooth wear were largely unaffected by confounders. These associations were also robust against outliers. A relevant association with flow rate was not detected. ConclusionThis study shows that salivary pH was inversely associated with tooth wear severity even after correction for confounders, such as flow rate, age, and sex. This association was especially significant for SWS. Although no causal relationship can be established, the results suggest a role of salivary pH in tooth wear in patients with moderate to severe tooth wear. No association was found between tooth wear and flow rate.

Mechanical damage induction mechanisms and process optimization of drilling considering cortical bone material heterogeneity

Mechanical damage induction mechanisms and process optimization of drilling considering cortical bone material heterogeneity

Chemical characterization of polymer and chloride content in waste plastic materials using pyrolysis - direct analysis in real time - high-resolution mass spectrometry.

The increasing global demand for plastic has raised the need for effective waste plastic management due to its long lifetime and resistance to environmental degradation. There is a need for rapid plastic identification to improve the mechanical waste plastic sorting process. This study presents a novel application of Temperature-Programmed Desorption-Direct Analysis in Real Time-High Resolution Mass Spectrometry (TPD-DART-HRMS) that enables rapid characterization of various plastics. This technique was applied on four commercially available reference polymers (polyethylene, polypropylene, polystyrene, polyvinyl chloride) as well as three "waste" plastic samples of mixed origin. These waste plastic samples were obtained as discards from various industrial processes with limited analytical characterization data. Through the application of CH2 Kendrick mass defect (KMD) grouping, characteristic trends in the mass spectra of each sample were identified, allowing for a simplified numerical comparison. This approach utilized a robust statistical approach using the Tanimoto coefficient, allowing for the quantitative measures of similarity between standards and unknown samples. The application of this mathematical evaluation methodology was used to identify plastic types and to distinguish structurally similar polymers. Additionally, we report that a chloride ion clustering effect with copper substrate can identify chlorinated polymer PVC (polyvinyl chloride) utilizing pyro-(-)DART-HRMS mode. PVC polymer is of particular interest in recycling due to its high chloride content, which can present technical challenges for some types of recycling. We found that chloride ion clusters are a good screening marker for the presence of chlorinated polymers in mixed waste plastic samples. This study can possibly help advance rapid and accurate analytical techniques for identifying the composition of waste plastics to advance the effectiveness of the waste plastic sorting process.

Effect of different crystalline directions on the mechanical properties and processing maps of Zr-Nb alloy for orthopedic applications

Effect of different crystalline directions on the mechanical properties and processing maps of Zr-Nb alloy for orthopedic applications

Survival and reproduction effects of microplastics from three agricultural mulching films on Folsomia candida, Sinella curviseta, Heteromurus nitidus and Ceratophysella denticulata (Collembola).

An estimated 467 kt of plastic used in agriculture annually end up in European soils, potentially breaking down into secondary microplastics (MPs). Not much is known about the possible effects of these MPs on organisms residing in the soil. To properly assess their environmental risk, experimental data is needed on the toxicity of MPs to the survival and reproduction of model organisms. This study aimed at assessing the toxicity of three MP types derived from commonly used agricultural plastics to different Collembola species, representing an important and highly diverse class of soil arthropods. Starch- polybutadiene adipate terephthalate blend (starch-PBAT blend) MPs were produced from mulching films that were artificially aged by mechanical recycling. MPs were also made from virgin low density polyethylene (LDPE) mulching films and from linear low density polyethylene (LLDPE) films that underwent the same mechanical recycling process as the starch-PBAT blend films. Four Collembola species were tested: Folsomia candida, Sinella curviseta, Heteromurus nitidus and Ceratophysella denticulata, representing epedaphic, hemiedaphic and euedaphic, as well as sexually reproducing and parthenogenetic species. Each species was exposed in Lufa 2.2 soil spiked with nine MP concentrations: 0.0016, 0.008, 0.04, 0.2, 1, 2, 3, 4 and 5% (w/w dry soil) and a control without additional MPs added to the soil. No dose-dependent effects were found for any of the exposed organisms, to any of the MPs tested. The results of this study suggest that the MPs used in this study, derived from commonly applied agricultural plastics, do not pose an immediate hazard to Collembola.

MASKE: A Kinetic Simulator of Coupled Chemical and Mechanical Processes Driving Microstructural Evolution

MASKE: A Kinetic Simulator of Coupled Chemical and Mechanical Processes Driving Microstructural Evolution

Neural Network Potential for Uranium-Niobium Alloy and Molecular Dynamics Study of Its Low-Temperature Aging Behaviors

Uranium-niobium alloys exhibit complex crystal phases and unique mechanical behaviors under various thermodynamic states and external loadings. However, the lack of accurate interatomic potentials hinders people’s understanding of the atomic-scale phase behaviors and dynamical processes in this important alloy. In recent years, the development of machine-learning-based force fields has provided a systematic way to generate accurate interatomic potentials on large and complex first-principle-based datasets. However, this crucial nuclear material has received limited attention from researchers in the field of machine-learning potentials.<br>In this work, based on our previous development of the neural-network potential training and evaluation framework, which we called NNAP, a new neural network potential is constructed for the uranium-niobium alloy system. We employ a combination of random structure search and active learning algorithms to enhance coverage of the chemical and structural space of the alloy system. Testing of the generated potential demonstrates high generalization performance and accuracy. The mean absolute errors in energy and force are 5.6 meV/atom and 0.095 eV/Å on the testing set, respectively. Further calculation results of crystal structure parameters, equation of state and phonon dispersions coincide well with the first-principle or experimental references.<br>Based on the newly trained potential, we investigated the atomic-scale evolution of the spinodal decomposition process in the U-Nb alloys. We show that the atom-swapping hybrid Monte Carlo can be a powerful tool to understand the thermodynamic evolution of the systems. By employ the atom-swapping hybrid Monte Carlo method, the potential energy reduce due to phase segregation is captured within 5000 steps, while no significant energy reduction is found after 3 ns MD simulation. Finally, we calculate the stress-strain curves under shear loading for different initial states. We found that the Nb precipitation generated strengthened phases in the alloy and significantly changed the deformation behavior of U-Nb alloys, where a disorder shear band emerges in the deformation path of the γ phase alloys. Our work lays a new foundation to understand the mechanical processes in this important alloy system.

Analysis and Experimental Study of the Composite Mechanical Bulging Process for Medium-Duty Commercial Vehicle Drive Axle Housing

Analysis and Experimental Study of the Composite Mechanical Bulging Process for Medium-Duty Commercial Vehicle Drive Axle Housing

2B-OLEFIN Film Development

As Pelsan Tekstil, in order to bring sustainable solutions to the use of polymers in the world, we have developed the world's first biodegradation technology that can provide full microbial conversion of polyolefins in open environment. This technology can provide full biodegradation on PP & PE materials. The advanced catalytic system converts PP and PE materials into wax. Unlike oxo-degradation, no microplastics or toxic substances are left behind in the post- degradation stage, thanks to a bio-available wax that naturally occurring microorganisms can easily assimilate. According to research, polymer use in the world is over 311 million tons. While the demand for polymers is projected to increase by 5.1% between 2020 and 2030, the recycling rate is only 14%. The non-recyclable portion accumulates as waste in soil and oceans. Biodegradable polymers are biodegraded by various microorganisms and enzymes in nature and broken down into their natural components. Thus, they can be recycled into the natural cycle without leaving microplastics. However, they are considerably more expensive than non- biodegradable polymers. In addition, biodegradable polymers are very vulnerable to heat and are damaged during extrusion. Therefore, our project goal is to make our product biodegradable by using an optimum amount of additives with our standard polyethylene film production formulation without making any changes in the technologies we already use. The biodegradation process is dominated by different factors including polymer properties, the type of organism and the nature of the pretreatment. Polymer properties such as the mobility of the polymer chains, crystallinity, molecular weight, the type of functional groups and substituents present in the structure, the plasticizers or additives present, all play an important role during degradation. The additive has the ability to promote different chemical reactions upon the polymer structure simultaneously. Our individually formulated additive acts as an initial food-source for microbes to help boost the biodegradation in the early stages of decay. The technology is fully compatible with normal mechanical recycling processes. No adverse impact on the mechanical characteristics and optical aspect of recycled products when mixed into the standard recycled supply chain.

ANALYSIS OF SINTERED ZrXEr1-X OBTAINED THROUGH POWDER METALLURGY

This paper aims to analyze Zr-Er sintered compounds obtained through powder metallurgy, with different concentrations, able to store H2. To obtain Zr-Er sintered compacts, in the first phase, zirconium and erbium were hydrides separately, at 750°C in a hydrogen atmosphere, for two hours each, to obtain zirconium and erbium hydrides. Using XRD analysis, both zirconium and erbium formed ErH3 and ZrH2. After the mechanical processing, morphological analysis performed by scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS) revealed microparticles with sizes ranging from 8.08 µm to 27.16 µm for ZrH2, 3.72 µm to 17.86 µm for ErH3. The mixtures of hydride powders were pressed in a cylindrical mold, and two ZrxEr1-x(x=0.25;0.75) pressed compacts were obtained. These samples were subjected to a heat treatment, in a helium atmosphere, that included a dehydrogenation treatment, followed by a sintering treatment, at 1200°C, for two hours. The compounds obtained were geometrically characterized, their experimentally determined density being more than 90% of their calculated density. SEM analysis of the sintered compounds revealed a densification of zirconium and erbium particles, and also, the higher the zirconium content, the more pores the sintered sample has. SEM-EDS microstructural analysis shows a uniform distribution of the component elements, and an increased tendency of erbium to oxidize.

ON THE ISSUE OF AUTOMATION OF THE SECTION OF MECHANICAL PROCESSING OF POLYSTYRENE PARTS

The paper proposes a consolidated model of the analysis of industrial production in order to assess the possibility and expediency of automation of the existing production process. The main parameters of the processing objects, which affect the decision-making regarding the automation of the process of its manufacture, are revealed. Based on the analysis of the configuration, geometric parameters, features of the location of the complex profile surfaces of polystyrene parts, as well as the analysis of their manufacturability, a conclusion was made about the possibility and expediency of automating the area of mechanical processing of such parts. Special attention was paid to the analysis of existing technological processes of processing typical parts. As a result of the analysis, a set of requirements for the structure and parameters of the new automated technological system was formed, as well as a new technological process for processing a set of parts was proposed. On the basis of the formulated requirements, the software type and machine level of automation of the technological system were chosen, the basic element of which was the manipulator robot. For the selected type of technological system, a new complex technological process of processing a set of parts has been developed, which involves minor changes in the design of some parts, which does not affect their functional purpose. For the implementation of the proposed technological process and the formed requirements for the equipment, specific main elements of the system were chosen - a robot-manipulator and a power unit, as well as a cutting tool, which allows processing of almost all parts of the set without replacement during the work. This made it possible to offer an option of an automated workplace, equipped with two working rotary tables for setting workpieces. The proposed version of the automated technological system and its implementation made it possible to significantly reduce the auxiliary time of mechanical operations, release highly qualified workers and reduce the cost of manufacturing parts.

Intrinsic Mechanical Parameters and their Characterization in Solid‐State Lithium Batteries

AbstractThe most critical failures in solid‐state batteries, including interfacial detachment, cracks, and dendrite growth are coupled with or fundamentally belong to a class of overarching phenomena that may be broadly defined as mechanical processes. However, current research on mechanical processes is far from sufficient, and is in its infancy compared with studies of improving electrolyte ionic transportation and electrochemical stabilities. Even the physical significance of many mechanical parameters has not been clarified in this field and the corresponding characterization methods have not yet been widely established. Herein, this review focuses on the intrinsic mechanical parameters associated with the design and operation of solid‐state batteries and their characterization. Beginning with an overview of mechanical processes, key concepts in the context of solid‐state batteries (SSB) are defined. Next, the various characterization methods that have been applied to SSBs are described in detail, and the key results are reviewed. Additional methods applied in orthogonal areas are also included to emphasize the possible translational impact on the solid‐state battery field. Finally, perspectives on the challenges and development trends in mechanical characterization are proposed for further development in solid‐state batteries.

Increasing the post-repair resource of the wheels attachment bolts of transport machinery

Abstract. Problem. The state of war in our country and a significant reduction in the production of new vehicles exacerbated the problem of increasing their operational resource due to repairs. Improving the quality and increasing the efficiency of transport vehicles involves, first of all, the fight against wear and tear, because the reason for their premature failure (from 75 to 90%) is significant wear and tear of parts. A significant number of parts of the main structural units of vehicles are exposed to cyclic loads, so it is quite reasonable to pay attention to the issue of increasing the fatigue strength of products. Considering the significant shortage and high cost of spare parts, an expedient and economically beneficial solution to these problems is the restoration and strengthening of the surface layers of products during repair The parts that mostly fail prematurely and require repair using rational methods of recovery include the bolts of fastening the wheels of buses - a very common vehicle that is intensively operated in very difficult conditions. The development of effective technological processes for the restoration of bolts with a simultaneous increase in the post-repair resource at the lowest costs is definitely an urgent issue, because it will prevent another possible premature failure in operation Goal. The purpose of the work is to restore and increase the post-repair resource of the bolts for fastening the disks of the rear wheels of the bus. Methodology. The subject of the study were the serial bolts for fastening the discs of the rear wheels of the bus made of 40X steel after quenching and tempering at 500-550º C with a trostite-bainite structure and a hardness of 35-37 НРС. For vibro-arc surfacing, electrode wire Нп-30ХГСА with a diameter of 1.2 mm was used. Food carbon dioxide was used as a protective gas, and a 5% solution of soda ash in water was used as an accelerating coolant. After surfacing, the surface was subjected to bombardment with low-energy (up to 3 keV) titanium ions in an argon environment at the Bulat - 3t installation. After the specified methods of bolt processing, the roughness and surface profile were evaluated, the microstructure was studied, and the mechanical properties were determined. The strength limit of the slotted part of the bolt was determined using special samples on the CD10 universal machine (made in Germany). Cyclic tests of welded samples were carried out according to the scheme "tension during rotation of the cantilever-loaded sample" on the UMP-02 machine. Tensile tests were performed according to standard methods. Originality. To increase the cyclic durability and wear resistance of bolts, a modern method of surface modification was used - ion bombardment with low-energy ions (without coating), which made it possible to strengthen the surface layer without losing plasticity. An increase in the resource was achieved due to a change in the state of the surface (obtaining ultrafine crystalline nano-sized grain, healing of surface stress concentrators), and a change in the mechanism of plastic deformation - from dislocation to rotational with grain-boundary sliding of ultra-fine grains. Practical value. The recommended mode of vibro-arc surfacing provides surface hardness for the possibility of further mechanical processing without additional thermal weakening, which increases the cost-effectiveness of the process of compensation of the worn surface layer. Modification of the surface by ion brombarbing after surfacing made it possible to increase the cyclic durability by 2 times, significantly increase the static strength without loss of plasticity, and increase the hardness to ensure wear resistance.

Numerical Simulation of the Basal Scraping Effect of Debris Flows Based on the Distance-Potential Discrete-Element Method

High-speed and long-runout landslides constitute one of the most devastating natural disasters. The scraping and erosion of the foundation by these landslides significantly alter the dynamic and catastrophic properties of the landslide mass. This study centered on the movement process of the landslide mass, utilizing numerical simulations to delve into the interactions and dynamic mechanisms between the landslide mass and the foundation. It examined how the erosion of the foundation by the landslide mass impacts its movement distance and accumulation pattern. By employing the distance-potential discrete-element method, which was proposed by the authors, this research simulated the movement process of the landslide mass from a mesoscopic viewpoint. Through precise characterization of the contact forces between blocks, the study sheds light on the interactions among blocks and the energy transfer process during the landslide movement. Furthermore, a comparative analysis was performed to assess the movement distance and accumulation pattern of the landslide mass under varying foundation conditions. The findings revealed that the distance-potential discrete-element method effectively captures the impact and scraping action of the landslide mass on the foundation. The block units within the scraping zone, stimulated by the landslide’s impact and scraping, transition from a stable to a dynamic state. Under the influence of unbalanced forces, these units exhibit rotational and forward-moving motions. The kinetic energy among the blocks is progressively transferred from the rear of the scraping zone to the front through contact interactions and is continuously dissipated through contact, friction, and other mechanical processes, ultimately resulting in a stable accumulation. Due to the scraping zone’s influence, the movement distance of the landslide mass decreases compared to rigid foundations, but the volume of the accumulation increases.

Achieving over 20 % Efficiency in Laminated HTM-Free Carbon Electrode Perovskite Solar Cells through In Situ Interface Reconstruction.

Laminating a free-standing carbon electrode film onto perovskite film is a promising method for fabricating HTM (hole transport material)-free carbon electrode perovskite solar cells (c-PSCs), offering more flexibility by decoupling the processes of carbon electrode and perovskite layer formation. However, the power conversion efficiency (PCE) of laminated HTM-free c-PSCs (<16.5 %) remains lower compared to c-PSCs with printed carbon pastes (>20 %), primarily due to poor interfacial contact between the perovskite and carbon layers. Herein, we report a chemical-mechanical driven in situ interface reconstruction strategy to solve such interface contact issues. The in situ interface reconstruction is firstly triggered by methylammonium chloride (MACl) surface treatment to chemically activate the film and then mechanically laminate the carbon electrode onto the softened perovskite film under heating. The perovskite film undergoes in situ regrowth and the carbon film starts to cure simultaneously, dynamically reconstructing the perovskite/carbon electrode interface. A tighter and conformal contact is achieved, greatly facilitating the carrier transport and extract. Ultimately, a champion PCE of 20.31 % is achieved with enhanced stability. Our in situ interface reconstruction strategy which is combinating the chemical and mechanical process offers a new choice for the further design of low-cost and efficient HTM-free c-PSCs.

Measuring economic growth factors: Dynamic trends and prospects

Subject. The article is devoted to measuring the factors of economic growth. Objectives. The purpose is to identify and measure economic growth factors in Russian regions. Methods. To analyze economic growth, the study employs the apparatus of production functions. The toolkit is based on the Cobb–Douglas production function, which, with the help of some transformations, takes a dimensionless form, namely, the resulting indicator is the growth of gross regional product, and the index of physical investment growth and employment growth in the region act as independent factors. Results. We built production functions for regions of the Central Federal District, analyzed changes in production functions for individual groups of regions. Conclusions. The findings of our research of production functions of regions of the Central Federal District for 2010–2022 showed less uniformity in parameters compared with the study of 2000–2009. Investments yield less return. The mechanisms of the classical theory of economic growth do not work as effectively as 15-20 years ago. The main economic growth depends on the amount of labor employed in the economy. The shortage of employees can be overcome only by changing the economic structure, intensification of mechanization processes, and robotization of production.