Metal Processing Research Articles

Review on Zinc Isotopes in River Systems: Distribution and Application

Zinc (Zn) is an essential trace element widely present in rivers and plays a crucial role in ecosystems. Human activities have led to the extensive migration and dissemination of Zn in the environment. When the accumulation of Zn in rivers reaches excessive levels, it transforms into a potentially harmful contaminant. Consequently, tracing Zn’s origin by its isotope ratios (δ66Zn) from natural and anthropogenic sources is essential for the management of and safeguarding against river pollution and comprehending Zn behavior in rivers as well. This review presents the advancements in Zn isotope research in river environments, including a summary of Zn isotope measurement, the distribution and controlling factors (mineral adsorption, precipitation, and biological effects) of Zn isotopes, and the applications of Zn isotopes in rivers. The median δ66Zn values for uncontaminated river water and suspended particulate matter (SPM) were 0.37‰ and 0.22‰, respectively, close to the bulk silicate Earth (BSE) value of 0.28 ± 0.05‰. With respect to the contaminated river, δ66Zn falls within −0.73‰ to 1.77‰, with it being heavily influenced by anthropogenic sources, such as the electroplating and metal processing industries. Apart from contamination identification, this review summarizes the river material exchange process and the δ66Zn values of rainwater (−0.2‰~0.38‰), groundwater (−0.13‰~1.4‰), lake water (−0.66‰~0.21‰), and seawater (−1.1‰~0.9‰), which facilitates a holistic understanding of the Zn cycle and isotope fractionation in the river system. In conclusion, Zn isotopes are an effective tool for tracing pollution sources and Zn migration processes, with enormous unexplored potential. Therefore, this review finally summarizes some challenges and future directions in current research on Zn isotopes.

Detrimental Effects of Metal Foil’s Surface Imperfections on Metal Plating/Stripping and Facile Solutions

Rechargeable metal batteries have attracted great interest and are considered one of the most promising high-energy density storage systems. These devices benefit from the large specific volumetric capacities and high specific gravimetric capacities of metal anodes. Foils or sheets are the most common form of anode for metal batteries since they are massively manufactured and readily accessible. But short circuits from dendrites grown on metal foil anodes can dramatically decrease the cycling stability and lead to premature failure of the batteries.Homogeneous metal plating/stripping is the key to avoiding dendrite formation. And the surface uniformity of metal electrodes is crucial for the initial nucleation and growth, which greatly affects the subsequent deposition. Here, we show that manufacturing-induced defects, including surface imperfections such as a roughened surface, orange peel features, microcracks, scratches, or fold lines, and unpolished edges from cutting can all promote local dendrite growth, leading to drastically decreased cycling stability of the demonstrated Zn metal batteries and K metal batteries. Polishing the metal electrodes on both sides and edges is shown to be effective to improve the electrochemical homogeneity of the metal anode and extend the cycling lifespan by over 700% in the demonstrated Zn metal cells. Finally, we demonstrate a simple and rapid surface passivation strategy that drastically increases the tolerance of such defects in Zn metal batteries. Also, we proposed a scalable, easily automated, and facile metallic K manufacturing with robust performance in K metal batteries.Since such imperfections are ubiquitous in commercially available metal foil products. Our results remind researchers about the significant detrimental effects of these very common defects introduced by metal manufacturing and processing, which should be taken into consideration evaluating metal battery performances. Furthermore, we call for research efforts to develop effective strategies that are scalable, easily automated, and cost-effective to increase the tolerance of batteries over such defects, which will be very important for large-scale, cost-effect energy storage hubs.References Pan He and Jiaxing Huang. "Detrimental effects of surface imperfections and unpolished edges on the cycling stability of a zinc foil anode." ACS Energy Letters, 2021,6,1990-1995.Pan He and Jiaxing Huang. "Chemical passivation stabilizes Zn anode." Advanced Materials, 2022, 34, 2109872.Pan He and Yang Xu. "Facile manufacturing potassium metal anode with robust performance". In preparation. Figure 1

Using ultrasound to increase copper and nickel dissolution and prevent passivation using concentrated ionic fluid.

This paper uses targeted ultrasound on a surface undergoing anodic dissolution. The aim of these experiments was to etch metals that would normally passivate. The study was carried out in deep eutectic solvents (DESs) as these are technologically useful for metal processing but suffer the disadvantages of being viscous and hence have slow mass transport which results in metal passivation. Linear sweep voltammetry showed a linear current-voltage response at potentials anodic (more positive) of the oxidation potential under sonication. Passivation was observed in silent conditions. It was also shown that the dissolution current was roughly 14 times larger under sonication. High speed imaging showed asymmetric bubble collapse leading to enhanced removal of material from the surface with etch rates as high as 3.8 μm.min–1 under ultrasonic conditions.

Secondary metallurgy at machine-building plants

Metallurgical production in foundries of machine-building plants is characterized by a number of specific features due to a wide variety of products, particularly stringent requirements for the quality of the metal produced, as a rule, for a responsible purpose. Accordingly, the foundry of machine-building plants is equipped with the most advanced technological equipment of various types with wide technological capabilities. It is no coincidence that it was at machine-building enterprises that the main types of secondary processing units were first used. Therefore, the history and current state of secondary metal processing at machine-building plants needs to be studied in detail. The metal is refined both in preparation for casting and directly in the casting process. It should be noted that the foundry does not take full advantage of the available wide technological possibilities of modern refining methods, some of which are discussed in the article.

Development of an all-solid-state air-cooled high-power blue diode laser for metal processing.

We present the design and development of an all-solid-state (fluid/refrigerant-free) 100 W scale blue-laser system and show its applications in precision copper works. We combine powerful laser-diode arrays with Peltier chips on a compact laser head to achieve stable thermal and optical performance. Good agreement between the thermal simulation of the 3D laser head and experiments validates stable thermal performance. The laser system emits 40-100W continuous wave at λ = 452.2 ± 2.5 nm with 98% power stability and ∼24% wall-plug efficiency inside a portable enclosure. This is the first, to the best of our knowledge, all-solid-state air-cooled laser with a 100 W class output. We achieved kW/cm2 intensity level on an mm-size focus with this source and demonstrated cutting, bending, and soldering copper on a battery pack. Furthermore, the copper-solder joints have nanoscale adhesion without cracks. Additionally, we unveil that 0.5-4 kW/cm2 intensity laser annealing scan makes copper strips mechanically resilient to withstand extreme loading cycles without nanoscale cracks.

Numerical analysis of arc physics and energy transfer under circumferential gas constraint effect

Energy dispersion and easy instability associated with arcs, the traditional metal processing heat source, restrict its development and application in the modern high-precision welding and additive manufacturing. This work aims to study the characteristics of a novel arc under circumferential gas constraint effect which can improve the arc stability and processing accuracy. A magnetohydrodynamics model was established to calculate the arc physics and heat transfer, considering the electron emission characteristics of tungsten and the effect of metal vapor. It indicates that the annular flexible constrained gas flow can significantly increase the physical characteristics such as arc temperature, plasma flow velocity and current density compared with traditional free arc which is named GTA. The arc heat generation increasement of the novel arc makes the heat transfer from arc to base metal higher than that of GTA. The additional annular gas flow inhibits the diffusion of metal vapor, stabilizing the arc and protecting the tungsten electrode from contamination. However, as the arc length decreases, eddy of arc plasma flow appears inside the arc, which can cause metal vapor to contaminate the tungsten. It's found that this novel gas flow constrained arc needs to be applied with a small current when welding with small arc length to avoid the eddy. Finally, the accuracy of the calculation model is verified by experimental detection of arc temperature.

Technology for the production of sickles and knives of the Petrovka Culture of the Southern Trans-Urals (by the results of metallographic analysis)

The data of the metallographic study of sickles and knives (37 pcs) of the Petrovka Culture from the Southern Trans-Urals and the Middle Tobol River basin of the 19th–18th centuries BC are reported. The implements originate from settlements (Ustye 1, Kulevchi 3, Starokumlyak, Kamyshnoe 2, Ubagan 2, Nizhneingaly 3) and burial complexes (Ozernoe 1, Krivoye Ozero, Verkhnyaya Alabuga). The reconstruction of the manufacturing technology of the Petrovka Culture tools from the Southern Trans-Urals was carried out by both taking into account the results of the surface visual inspection, as well as by the data of the microstructural study of the metal. The metallographic analysis was conducted at the Tyumen Scientific Center of the Siberian Branch of the RAS (microscope Axio Observer D1m from Zeiss; microhardness tester PMT-3M from LOMO). A certain correla-tion was revealed between the functional purpose of the product, type of the raw material, and the tool manufacturing flowchart. The sickles and knives with handles are produced primarily from pure copper (including oxidised) both in the process of casting in mould with subsequent finishing, as well as in the result of the forming forging. The tools obtained in the casting process often had casting defects, accompanied by the phenomenon of shrinking warpage of the metal. The finishing of the copper tools was taking place in most cases either in the regime of incomplete hot forging at 300–500 C, or hot forging at 600–800 C and at near-melting temperatures of 900–1000 C. Most of the sickles in the forging process were purposefully hardened by forging on the cold metal. Unlike the sickles and knives with handles, shank knives are made mainly of low-alloyed tin bronze. Apparently, this category of tools was given a special ritual significance, especially considering the fact that about a third of the tools came from burial complexes with a specific selection of the related implements. The use of tin bronze in the production of knives sig-nificantly contributed to the fabrication of high-quality castings with the smooth surface without metal warping defects. The fini-shing of the knives after casting was carried out with heating up to 600–800 C or 900–1000 C (44 % of the tools) or in the regime of incomplete hot forging (25 %). The forging on the cold metal with annealing was rarely used. Thus, at the basis of the choice of the technological traditions of the metal production lies the availability of a certain raw material base, the type of the metal obtained from this ore, as well as the inheritance of the technologies from the preceding cultural communities. Technological inno-vations in the processing of non-ferrous metal, associated with the supply of Sn-bronzes in the form of ingots or finished products from Central Kazakhstan to the Southern Trans-Urals, led to the significant increase in the quality of the produce.

Tools for the metal processing of the Alakul population of the forest-steppe Tobol River basin

The paper presents the results of the study of a tool complex associated with metalworking from the sites of the Alakul Culture of the forest-steppe Tobol River basin — the settlements of Kamyshnoe 1 and 2, Uk 3, Nizhneingalskoe 3, and Zolotoe 1. The Alakul antiquities, in general, date to 1900–1450 BC. The purpose of this work is the consolidation and clarification of information on the metalworking of the Alakul population of the forest-steppe Tobol basin. For this purpose, collections of trade tools of the aforementioned Alakul settlements were revisited; the tools used in the production in question were identified; the signs of their wear, documented by a series of microphotographs, were characterised; and groups of the tools were identified according to their functional feature. The main research method was experimental-traceological. It implies, firstly, the study of traces of wear, their mutual occurrence and specifics of the location on the tools; secondly, the comparison of the obtained characteristics with experimental data. In the work, theoretical and experiential concepts of the methodology and classification schemes developed by S.A. Semenov, G.F. Korobkova, and V.V. Kileynikov were employed. To verify the traces of wear on archaeological tools, experimental reference samples of the tools were used, obtained during many years of work and stored in the Tyumen Scientific Centre SB RAS. As analogies, published results of the experiments and experimental and traceological studies of similar tools from territorially close Bronze Age sites were used. As the result, forging tools (hammers for cold and hot forging of castings, smoothers) and abrasive tools were identified; their technological characteristics and distinctive signs of wear marks were clari-fied. A set of tools in one quantity or another was recorded at each of the studied sites; therefore, the blacksmith production was quite developed also on the periphery of the Alakul Culture. Additional arguments were obtained in favour of the hypothesis that the ore processing was taking place in the immediate vicinity of its sources, and the metal could have been supplied to the re-mote villages already in a ‘finished’ form; there, the products were cast, forged, and finished. Analogies to the studied tools are known from the earlier Petrovka and Sintashta complexes of the Southern Trans-Urals. Thus, we can talk about common patterns in the manufacture and use of metalworking tools during the Bronze Age in the Trans-Urals territory.

Specific energy consumption of electro-contact-chemical treatment of metals with a vibrating tool in the electrolyte

According to the specific energy consumption, the shaping processes are arranged in three energy levels. Electrophysical and electrochemical methods of metal processing are at the third level, where the specific energy consumption is more than 6∙104 J/cm3. The analysis of the literature data showed the inconsistency of the specific costs of some authors. The specific energy consumption of electrical contact processing cannot be commensurate with the costs of electrochemical processing due to the different sizes of the particles removed from the surface of the workpiece. There are no literature data on the specific energy consumption of electro-contact-chemical treatment of metals with a vibrating instrument in the electrolyte, therefore, experiments have been carried out with the fixation of current, voltage and interelectrode gap oscillograms. The method of calculation of specific energy consumption according to the oscillograms of the process is given. The energy costs for vibration of the electrode-tool are calculated, which are an order of magnitude less for electro-contact-chemical treatment. When the vibration amplitude decreases or the voltage on the electrodes increases, the process in the interelectrode gap turns into dimensional arc processing. When electro-contact-chemical treatment of metals with a vibrating tool in water, the specific energy consumption is equal to (3.5–3.8) · 105 J/cm3, which corresponds to electrocon-tact treatment. It is assumed that the use of aqueous solutions of neutral salts will lead to a reduction in energy costs.

Inertial migration of fine mineral particles in a curved microfluidic channel: Demystifying the role of non-neutrally buoyant particles

Fine mineral particles (FMPs) are ubiquitous in hazardous waste derived from metal mining, processing, and smelting. Inertial microfluidics has sparked tremendous attention due to its potential applications in separating neutral buoyant particles. However, it often fails when applied into non-neutral buoyant FMPs. The inertial migration and focusing tendencies of FMPs were still unknown. Herein, we present a modified microfluidic experiment platform to ensure the steady flow of FMPs in microfluidic systems. This platform avoids the deposition issue of FMPs by combined sample input and suspension system along with design of effective flow rate. FMPs of various particle diameter (2.2 μm, 6.8 μm and 10.2 μm, density of 6.29 g/cm3 or 3.2 g/cm3) were classified and compared to neutral buoyant particles (1.1 μm, 7 μm and 9.9 μm, density of 1.05 g/cm3) to investigate their differences in migration and focusing behaviors within a curved microfluidic channel (CR = 0.07). The migration dynamics of particles with multiple scale sizes may be divided into focusing, rough focusing, and non-focusing modes. Results revealed that a high density of FMPs had less effect on FMP migration and focusing behaviors in three modes. Nonetheless, the variability of FMP size and shape must be considered, as it will induce a shift in particle focusing position and, ultimately, might inhibit FMP separation in microfluidic channels. This work provides an experimental basis for the microfluidic behaviors of FMPs and might give advanced support for the possible application of microfluidic technology in mineral particle separation and sorting.

КОНСЕРВАЦИОННЫЕ И РАБОЧЕ-КОНСЕРВАЦИОННЫЕ СМАЗОЧНЫЕ МАТЕРИАЛЫ «РОСОЙЛ»

The paper contains an overview of Rosoil rust-preventive, protective and operating lubricants for metallurgy, mechanical engineering and other industries, including for military-industrial enterprises, as well as for the needs of the Ministry of Defense of the Russian Federation and the population. The main physicochemical and operational characteristics of rust-preventive, protective and operating lubricants are given such as rust-preventive greases for corrosion protection of ferrous and non-ferrous metal products during storage and transportation; protective grease lubricants for anticorrosive and mechanical processing of metals; protective antifriction greases for lubrication when manufacturing and operationing steel ropes made of uncoated wire and galvanized wire; universal lubricants for multi-purpose applications; corrosion-preventing oil for protection of military equipment; gun oils for cleaning, lubrication and corrosion protection of artillery and small arms during storage and operation; corrosion inhibitors to improve the protective properties of lubricating oils for various purposes and fuels. It is shown that the range of Rosoil rust-preventive, protective and operating lubricants contains 19 products, most of which are designed to replace imported materials and surpass them in protective properties and tribo-engineering characteristics.

Fugitive Dust Associated with Scrap Metal Processing

Fugitive dust (FD) is a nuisance and potential health issue, particularly in environmental justice communities that can experience high levels of contaminated FD. This community-initiated study examined FD from a scrap metal processor in Detroit, Michigan, to determine whether the FD was contaminated, how it migrated through the community, whether wipe or composite road dust samples were preferable, and whether literature profiles adequately characterized this source. The study was motivated by community concerns, as well as a massive subsidence/upheaval event resulting from excessive accumulation of mill scale, which is a type of scrap metal, at the facility. We collected 57 wipe samples from windows and other surfaces, and 20 composite road dust and surface soil samples, which were analyzed by X-ray fluorescence. Concentrations were expressed using the fraction of the reconstructed mass. We also compared results to air quality monitoring data and calculated pollution indices and enrichment factors. Samples collected near the processor had high levels of Cr, Cu, Fe, Ni, Sr, and Zn compared with background soils, and levels remained elevated in residential areas several blocks distant. Composite road dust/sediment samples appeared preferable to wipe samples for chemical characterization. The available chemical profiles did not match the FD composition, suggesting the need for local profiles. The high level of Fe, which is consistent with mill scale, was a novel finding and caused the road dust to exceed health protection screening levels. Numerous metal scrap facilities operate locally and nationally, and our results show the need to improve controls to limit or eliminate FD emissions from industrial sources using enforced policies that reduce dust generation and truck track-out.

NIOBIUM IN COPPER AND COPPER-BASED ALLOYS. REVIEW

In the scientific and technical literature review, investigated the use of niobium as an environmentally friendly and effective alloying addition to enhance the temperature stability of the structure and properties of copper products with an ultrafine-grained structure has been investigated. Considerable attention is paid to the potential of niobium as an alloying addition in the context of the innovative use of niobium to form a special «layer» at grain boundaries to strengthen its influence on the structure, especially the grain structure, and consequently on the properties of copper and materials based on it. The review of literature and informational sources devoted to the Cu-Nb phase diagram has shown that niobium is one of the most effective segregants to limit grain growth in binary copperbased alloys. Additionally, the efficiency of niobium as an alloying element that improves the grain structure and the mechanisms believed to underlie this phenomenon have been discussed. In particular, the use of alloying and liquid metal processing technologies for refining the grain structure of copper alloys has been examined. It has been elucidated that niobium in copper-based alloys is also used to enhance physicalmechanical and technological properties. The impact of microimpurities on the final structure of the copper-niobium alloy has been highlighted, imposing specific requirements on the purity of input materials and the technologies used to eliminate contamination from the melt and improve its homogenization. The review briefly discusses other methods that can be employed to form a special «layer» at grain boundaries. Specifically, technologies of mechanical alloying and methods of simultaneous deposition of component vapors in a vacuum have been studied. Based on the results of the literature analysis, the considerable prospectiveness of methods involving the simultaneous deposition of component vapors in a vacuum to create a special «layer» at grain boundaries has been demonstrated. The article examines the results of studies on niobium segregation at grain boundaries in the copper-niobium system and similar systems, establishing that the improvement of several described technologies and methods can be quite promising for the further development of technology for its implementation in production.

Efficiency of Low-Carbon Technologies Implementation at Non-Ferrous Metallurgy Enterprises under the Conditions of Carbon-Regulation Development in Russia

Carbon markets are highly relevant to the need to regulate man-made greenhouse gas emissions. As the world faces the dangerous effects of global warming, reducing greenhouse gas emissions has become a critical priority for governments, corporations and individuals around the world. Carbon markets offer a way to incentivize and encourage emissions reductions and facilitate a smooth transition to a low-carbon economy. Low-carbon development is possible by building transparent and understandable organizational and economic conditions for the operation of carbon regulation. This article considers the feasibility of introducing energy-efficient technologies at Polymetal International PLC enterprises located in Khabarovsk region, engaged in the mining and processing of non-ferrous and precious metals (gold, silver and copper) in light of the country’s growing attention to the regulation of carbon dioxide emissions. The objective of this study is to model the organizational and economic conditions of the carbon market and estimate the economic and climate outcomes from the implementation of energy-efficient technologies at Polymetal International PLC. This study analyzes the current energy-consumption structure of non-ferrous metallurgy enterprises in Russia and identifies potential areas for the use of energy-efficient technologies. An important aspect is the assessment of government policies and incentives that could facilitate the introduction of low-carbon technologies. It is important to assess the impact of prospective carbon-management plans in Russia on the economic performance of steel companies. The results of this study suggest that the introduction of low-carbon technologies has the potential to significantly reduce energy consumption, lower operating costs and reduce carbon dioxide emissions from non-ferrous metal companies in Russia. However, the successful implementation of these technologies will require significant investment, stakeholder cooperation and political support from the Russian government.

INTELLIGENT MODELS FOR CONTROL OF JET HYDRO-PROCESSING OF ROLLED STEEL DEFECTS

The structure of an intelligent control system for the hydro-processing of surface defects in rolled products is presented, which corresponds to the concept of the European program "Industry 4.0" in the direction of energy saving and total automation of processes.
 The considered local RBNN hydro-processing models are tuned using the Kaczmarz-Widrow-Hoff algorithm. The model for identifying the current task of the pressure of the processing fluid takes into account the relationship between the thickness of the processed defect, changes in the composition of the working fluid and, as a result, its abrasive properties. To form a given pressure in the corresponding jet, the following neural model estimates the duration and polarity of the voltage that controls the electric drive of the jet control valve in real time.
 The small-dimensional models’ conveyor is a promising solution for controlling waterjet processing of metals in such areas as rounding sharp edges; grinding and polishing complex surfaces; deburring and cleaning of welds; surface preparation for coating; removal of defects from the surface; high-precision waterjet cutting of metals. The solution will increase the speed of TP from 1.2 to 1.96 [m/s]. Taking into account the small dimensions of the models and the relatively low speed of the TP, a software application based on the proposed models can be implemented in the control system for the hydro-processing of rolled metal products in the form of an inexpensive IIOT microcontroller module.

Высокорельефная чеканка в казанско-татарской ювелирной традиции: историко-технический анализ

The article is devoted to identifying the origins and regional features of the technology of high-relief coinage in the Kazan-Tatar jewelry tradition. The main source was the electronic database of Tatar jewelry from museum collections, collected within the framework of the academic project “Jewelry of the Turkic peoples of Eurasia: general and special” (Russian Foundation for Basic Research 2013–2014, No. 13-06-97056). The research was based on a systematic technical and stylistic analysis of traditional jewelry and a detailed synchronous-diachronic examination of Bulgar-Golden Horde and Tatar products with three-dimensional images. Reconstruction of technological techniques related to this type of artistic metal processing made it possible to identify specific features of the formation of decor. The manual method of obtaining a unique relief using punches with a figured striker predominated. The decorations are characterized by the following: two or three-level bas-relief, the absence of a “locking” profile, the principle of “compositing” that underlies the conventionally interpreted floral and plant motifs, geometric orderliness, subject to the laws of the central-radial composition. The completed form of the decoration corresponds to the typical features of “notch chasing”, which is a marker of the Tatar craft tradition: smooth relief and “grain” background. An integrated approach allowed us to conclude that the origins of the existing artistic and figurative system can be traced in artifacts of the Bulgarian and Golden Horde silver of the 11th–14th centuries, made by embossing, stamping, and punching on a matrix. The formation of technological features was influenced by the traditions of high-relief coinage, which received regional development among Kazan silversmiths in the 17th–18th centuries. The specifics of Tatar relief coinage as a whole were formed in the context of Islamic art.

Effects of deposited particle energy on the structure and properties of diamond-like carbon films

Using plasma-enhanced chemical vapor deposition (PECVD), a series of diamond-like carbon (DLC) films were prepared on YG8 carbide substrate by changing the enhancement mode and the negative bias voltage of the substrate. The structure and properties of the deposited films were tested by a series of analytical and testing instruments.During the deposition of DLC films, the ability of electrons to collide and ionize the gas is enhanced by increasing the number of electrons and extending the movement path of electrons, which is called electron-assisted enhanced gas ionization. Four different experimental modes (A mode, B mode, C mode, D mode) were set up. Different experimental modes have different degrees of electron-assisted enhancement ability of gas ionization, so different experimental modes are called different enhancement modes. The ions ionized by the electrons participate in the deposition of the film under the traction of the negative bias voltage of the substrate. The results show that: when depositing diamond-like carbon films, the energy of the ion beam is indirectly affected by electron collisions in different enhancement modes and directly affected by the negative bias voltage of the substrate. The higher the enhancement mode, the higher the ion beam energy. The higher the substrate negative bias voltage, the higher the ion beam energy generated by gas source discharge. Under the dual action of enhancement mode and substrate negative bias voltage, the total energy of ions involved in deposition should not be too high or too low, and the synergy of the two makes the properties and quality of the deposited film reach a better value. For industrial large-scale production of tool protection film for cutting aluminum alloy, it is more suitable for high enhancement mode and low negative bias voltage production.Through a series of process optimization to improve and enhance the comprehensive performance of DLC film, it is further applied to the actual processing application field, which has great industrial and social value to realize the large-scale application of DLC film in the field of hard to cut metal processing.

Methods for Improving the Quality of Forgings and Blanks Obtained by Forging through Intensifying Shear or Alternating Strain in the Bulk of Deformable Metal

The article presents methods for improving the quality of forgings and workpieces obtained by forging by intensifying shear or alternating strain in the bulk of the deformed metal. To increase the metal processing due to shear or alternating strain during forging, forging strikers are most often used, the feature of which is the geometric configuration that creates additional metal flows. Quite a lot of works from research teams from all over the world have been devoted to the problem of intensive metal processing during forging. In these publications, a number of new unique designs of strikers have been proposed and various route technologies have been considered, which can significantly increase the level of shear or alternating strain compared with the use of traditional forging tool designs.

The influence of environmental factors on the health of the population of the Aktobe region.

This study investigates the impact of environmental factors on human health, including harmful substances, extreme temperatures, and air quality. The health status of the population in regions where many industries operate also depends on meteorological factors. The purpose of the study is to characterize and determine the influence of environmental factors (humidity, temperature, wind) and industries, including metal mining and processing regions, on the health of people in the Aktobe region, Republic of Kazakhstan. The study used general theoretical methods to analyze and systematize the results of the meteorological service of the Aktobe region and the experiments conducted by the branch of the National Centre of Expertise of the Committee of Sanitary and Epidemiological Control of the Ministry of Healthcare of the Republic of Kazakhstan for the Aktobe region in 2020 and 2021. Statistical data on the amount of chromium, lead, and nickel in the blood, and the morbidity rate of the population were analyzed. The study's findings indicate that residents in the Aktobe region experience hypothermia during winter at temperatures between -12 °C and -15 °C and humidity of 81%, and in summer overheating occurs at temperatures between +19.6 °C and +22.5 °C with humidity of 77%. These extreme temperature conditions disrupt the body's heat exchange with the environment, affecting the respiratory and circulatory systems. Moreover, the predominantly windless conditions in the region affect the atmosphere's self-cleaning ability, resulting in high levels of air pollution throughout the year. The findings can inform strategies to improve public health and prevent diseases in industrial regions. Integr Environ Assess Manag 2024;20:1156-1165. © 2023 SETAC.

Modeling of Stainless Steel Bending Force on CNC Press Brake

Bending processing is one of the most common plastic deformation processing procedures. It is widely represented in the metal processing industry. In this paper, sheet metal bending on a CNC press with a tool that has two basic parts is analysed: the lower-die and the upper-punch. The sheet metal material is stainless steel, which is one of the most commonly used materials. During the bending process on presses, one of the main challenges is the experimental determination of the bending force. The methodology used in this work is based on the experimental stochastic method, that is, design of experiment. A rotatable plan for three input parameters: material thickness, bending angle and bending line length, are varied at five levels. The output parameter is precisely the bending force. No special devices are needed to measure the bending force as an output parameter, because the bending force is measured and registered on the CNC press via the control panel. After the experiment, using the experimental design matrix, the coefficients of an adequate nonlinear mathematical model were determined. Such a mathematical model is suitable for analysis and optimization of the bending force.