Fulltext search in archive

In this work, the microstructure and properties of the first-Republic Czechoslovak circulation coins were studied. The variety of the coins at that time was shown. Significant differences in microstructure in the direction of forming and in the normal direction to the surface direction have been confirmed. For some coins, visible features of recrystallization were shown, which suggests the coinage at higher temperatures. The chemical composition of coin alloys was also studied. In most cases, it was consistent with the declared chemical composition by mint. Significant differences in the hardness of the coins were found, which confirmed the different experience of numismatics with the abrasive resistance and the preservation of different coins. The quality of the design and the material composition of the coins confirm the long-standing experience with coinage in the Czech lands, despite the fact that, after the Austro-Hungarian Empire, the mining industry was struggling with big problems (eg stolen raking machines, lack of Czech mining experts). The first-Republic circulation coins represent the best in the history of the Czech and Czechoslovak coinage industry.

The aim of this work is to verify the reliability of optical inspection of tires during their transport on a roller conveyor, with an emphasis on the accuracy of 3D scanning in real and simulated operating conditions. A measuring box was designed and constructed to eliminate environmental interference, and measurements were subsequently compared with different degrees of site coverage. Testing was carried out using a 3D sensor O3D302 operating on the Time-of-Flight principle, and spatial data in the form of point clouds were obtained and compared with the reference dimensions of the Nokian WR D4 tire. The effects of solar IR radiation, rain, surface moisture, and natural lighting conditions were analyzed, which caused different levels of deformation, noise, and measurement deviations. The results show that significant errors occur without coverage, while the measuring box significantly reduces these deviations and increases the stability of point data. Complete coverage from above and below proved to be the most effective solution, but the wet tire surface remains a significant source of interference. The work further proposes structural modifications to the box and recommends the application of a matte surface and the expansion of tests to include the effects of vibrations and real conveyor operation. The result is a technical evaluation of the measurements and recommendations for improving optical tire detection in the industrial process.

Vehicle Routing Problem is a common problem in logistics, which can simulate in-plant and out-plant material handling. In the article, we demonstrate a Vehicle Routing Problem, which contains period, time window and multiple depots. In this case, customers must be served from several depots. The position of the nodes (depots and customers), the demand and time window of the customers are known in advance. The number and capacity constraint of vehicles are predefined. The vehicles leave from one depot, visit some customers and then return to the depot. The above-described vehicle routing is solved with construction algorithms and Ant Colony algorithms. The Ant Colony algorithms are used to improve random solutions and solutions generated with construction algorithms. According to the test results the Elitist Strategy Ant System and the Rank-Based Version of Ant System algorithms gave the best solutions.

The goal of the study was to analyze the kinematic and dynamic response of the human head during the primary impact of tram-pedestrian collisions. The anthropomorphic test device (dummy) was used for two collision scenarios: the frontal (dummy facing the approaching tram) and side impact (dummy standing with its shoulder towards the tram). The crash tests were conducted with four different types of tram, typical for Prague’s public transportation, and at four different impact speeds (5, 10, 15, and 20 km/h). The primary outcome variable was the resultant head acceleration. The risk and severity of possible head injuries were analyzed using the head injury criterion (HIC15) and the corresponding level of injury on the Abbreviated Injury Scale (AIS). The results of the kinematic analysis showed that during the primary impact, the head of the dummy always got hit by trams’ front ends in the case of frontal impact while in the case of a side impact, the head got only hit at higher speeds (15 and 20 km/h) with modern tram types. The results of the dynamic analysis showed an increasing trend of head impacts with higher speeds for all tram types and collision scenarios. However, the head acceleration was higher in the case of frontal impacts compared to side impacts. The HIC15 did not exceed the value of 300 in any case and the probability of AIS3+ did not exceed 10%. The results suggest that the outcomes of tram-pedestrian collisions can be influenced by the tram type (its front-end design), impact speed, collision scenario, and the site of initial contact.

A single-stage evaporator with natural circulation was used to densify the plasticizing bath through continuous evaporation and to prepare a solution used in the production of viscose fiber. During the process, sodium calcium sulfate salts were formed, leading to fouling of the heat transfer surfaces in the heat exchangers. This fouling created a layer of deposits that gradually reduced the efficiency of the evaporation process in the evaporator. It was determined that a processing medium with a volumetric flow rate of 6 m³·h⁻¹ required a heat exchanger power of 1448 kW. A fouling layer with a thickness of 0.1 mm reduced the heat exchanger's performance by approximately 40%. When the fouling layer increased to 0.5 mm, the heat exchanger power decreased by nearly 74%, down to 889 kW. The purpose of this paper was to analyze the process parameters of the densification technology in order to identify potential optimisations that could increase equipment availability and reliability. Alternatively, the study aimed to provide recommendations for design modifications to the existing technology.

The cutting performance of abrasive water jet (AWJ) machining is commonly evaluated using cutting depth, cutting efficiency, and specific cutting energy. To systematically investigate the influence of process parameters on AWJ cutting performance, a five-axis CNC cutting platform was developed, allowing precise control of operating conditions. Single-factor experiments were conducted to analyze the effects of pump pressure, traverse speed, cutting angle, abrasive mass flow rate, standoff distance, and nozzle diameter. Both qualitative analysis and quantitative evaluation were employed to identify parameter ranges that maximize cutting efficiency or minimize specific cutting energy. The results indicate that the minimum specific cutting energy is achieved when the pump pressure is approximately three times the threshold pressure, the traverse speed is 110 mm/min, the cutting angle is 90°, and the abrasive mass flow rate approaches its optimal value. The effects of standoff distance and nozzle diameter on specific energy depend on their combined influence on cutting depth and kerf width. In addition, repeated cutting passes were found to increase energy consumption, indicating that complete material penetration in a single pass is more energy-efficient. These findings provide practical guidance and theoretical support for achieving high-efficiency and energy-saving AWJ cutting processes.

The given paper deals with the defects propagation in car tires for passenger vehicles under dynamic loading. The occurrence of defects has the significant influence on the lifetime and quality of the tire, especially during its operation as a part of the vehicle. The given defects are closely connected with a safety in road traffic. The aim of the study was to carry out a non-destructive analysis of the car tire for the purpose to analyze the defects propagation as well as to introduce the defects classification and their location along with the whole course of rupture as a result of increasing speed, loading and the number of hours or kilometers driven. During the analysis, we used a non-destructive method for detecting defects using a non-destructive analyzer that works on the principle of shearography. The experimental measurement was carried out for 12 car tires. The measurement results are displayed from the non-destructive analyzer in the form of protocols from measurement and video display. The evaluation of the results of the measurement for the propagation of defects is displayed graphically. In relation to the tire casing, the analysis of the defects propagation can help design engineers to solve critical issues by choosing the right material, modifying dimensions of individual components or even by redesigning the overall construction of the tire casing and thus to increase the safety from the as-pect of vehicle operation.

In order to solve the problem of heterogeneous deformation in the rolling process of 10Ni5CrMoV heavy plate, the effects of uniform temperature rolling (UTR) and graded temperature rolling (GTR) on the microstructure and deformation uniformity of 10Ni5CrMoV steel were studied by means of numerical simulation and verification experiment, and the strengthening mechanism of high permeability rolling process on the rolling deformation of 10Ni5CrMoV heavy steel was clarified. The results show that compared with the uniform temperature rolling process(UTR), different gradient temperature rolling processes (GTR) make the deformation area gradually expand to the core, and the deformation of the core increases significantly. The reduction rate of the first pass gradient temperature rolling processes (FGTR) is about 2.3% higher than that of uniform temperature rolling, and that of continuous gradient temperature rolling (CGTR) is about 5.3% higher than that of uniform temperature rolling. At the same time, the microstructure difference of the core surface is reduced, which is conducive to improving the uniformity of microstructure and properties. At the same time, the microstructure of the core in the rolled is uniformly refined, and the effect is significant.

The article describes the creation of a mathematical 3D model of the original hovercraft structure, which will be further used for research into modifying the shapes and materials of the structure to ensure better driving conditions. Proposals for new materials for individual parts of the hovercraft structure will be addressed in order to reduce the weight of the hovercraft and thereby ensure a higher possible speed of movement, reduce fuel consumption and ensure the necessary mechanical properties of individual segments. The mathematical model of the simplified hovercraft model was created in the Cradle and Adams simulation programs. The paper is presented by analyzing the hovercraft properties in order to obtain sets of advantages and disadvantages of the hovercraft. The following is a description of the creation of a geometric 3D model of the hovercraft, which is built using Autodesk Inventor. The article further describes the transformation of the 3D model into a simulation model that can be used for co-simulation of movement in the Adams and Cradle computer simulation systems. The simulations will be the first step towards modifying the structure of a real rescue UAV prototype with improved maneuverability, stability and the ability to traverse terrain with surfaces unsuitable for hovering.

Today, considerable attention is paid to the production of solid castings (approx. 2000 kg) from cast iron with spheroidal graphite. The metallurgical preparation of large quantities of melt is very difficult. This difficulty is related not only to the melting and preparation of large quantities of melt, but above all to its metallurgical treatment - inoculation and modification. Melt modification ensures the production of cast iron with spheroidal graphite. Material castings, such as machine tool components, cannot be destroyed to determine the quality of the cast iron produced. Therefore, this paper outlines a methodology to proceed in determining the quality of manufactured castings. It is possible to observe the chemical composition of cast iron, thermal analysis of cast iron using liquidus temperature value, subcooling temperature, eutectic recalescence, primary solidification recalescence, eutectic solidification time. Furthermore, to observe the mechanical values of cast iron (yield strength, ultimate strength and ductility) on fabricated bars of overmolded Y blocks or to observe the micro-structure of cast iron on microscope.

Determining the productivity and quality of precision AWJ machining requires routine and careful inspection of nozzle condition. The degradation of the inner bore of the nozzle adversely impacts the mixing efficiency and uniformity of the water jet, thereby affecting its cutting performance. In this study, new nozzle was designed and manufactured using additive manufacturing and were made of 316 L stainless steel. The new nozzle consists of two combined parts with the peculiarity of being easy to install using a screw thread. The wear behavior of the new nozzle was examined using an accelerat-ed wear test. An accelerated wear test was conducted on the hard abrasive silicon carbide (SiC) and compared to garnet, the abrasive commonly used in the AWJ industry. The aim of the test was to de-termine the wear pattern of the nozzle. The cumulative mass loss and nozzle diameter increase for different abrasives were measured. The geometric change in the nozzle is made visible through de-structive examination. The findings indicated that the type of abrasives significantly affects nozzle wear. As the hardness of the abrasive increases, the diameter of the nozzle enlarges, resulting in accel-erated nozzle wear. The mass loss factor of SiC abrasives is three times higher than that of garnet abrasives. This research allows practitioners to monitor the nozzle wear behaviour during the AWJ process. The results obtained were used to estimate the nozzle life based on the observed wear history.

The article is focused on the investigation of the impact of the implementation of mechanization into the welding workplace, for the production of cylinders from austenitic X5CrNi18 10 chromium nickel steel. The welds are assembled into a production line for the processing of puff pastry. In addition to the technical improvement of the process and the verification of the sufficient quality of the welds, calculations were used to prove that after the implementation of the change, there was a significant reduction in the production time. By introducing a higher level of mechanization and necessary technological changes, the production time was reduced by up to half, compared with the original technological procedure, including an increase in quality parameters and it led to a reduction in the production costs of the welding workplace. A significant consequence of the proposed change was connected with its impact on workplace safety.

In order to address the pollution caused by petroleum-based plastics and increase the added value of agricultural waste, this study aims to develop an environmentally friendly wood composite material using agricultural waste corncob (CC) and biomass material chitosan (CS) as the matrix, and optimise its molding process to improve its physical and mechanical properties. Based on the single-factor test, the relatively optimal process parameters were preliminarily determined as follows: the CS concentration is 1.8%, the pressure is 25 MPa, and the temperature is 135 °C. At this time, the comprehensive properties of the material reach a density of 1.47 g/cm³, a hardness of 16.67 kgf/mm², a flexural strength of 42.2 MPa, and an elastic modulus of 7.2 GPa. Furthermore, the response surface experimental design and analysis method was applied to optimize the composition ratio and molding process parameters, and a response surface model with flexural strength, apparent hardness, and density as response values was established. Through the analysis of the Design-Expert software, a quadratic regression equation was obtained, and its determination coefficient R² is higher than 0.9, indicating that the model is significant and reliable. The response surface analysis shows that the optimal parameter combination is a CS concentration of 1.7%, a molding pressure of 26 MPa, and a molding temperature of 138 °C. In the verification test, the flexural strength is measured to be 49.419 MPa, the hardness is 16.585 kgf/mm², and the density is 1.507 g/cm³, which is highly consistent with the optimized predicted values. The study shows that the response surface method can effectively establish a quantitative relationship model between process parameters and performance indicators, providing a reliable process optimization method and theoretical support for the green preparation of biomass composites.

In a vertical impact crusher, material particles undergo multiple impact collisions and eventually break due to accumulated damage. In order to further study the crushing mechanism of the crusher, a cumulative damage model of material particles under re-peated impact was established. Firstly, a crushing model is established based on the specific fracture energy, reflecting material particles' cumulative damage and crushing process. Then, the simulation model of the crushing system of the vertical shaft impact crusher is established. And by simulating the crushing process of limestone particles in a crusher, it reveals that the crushing of particles is essentially due to the crushing that occurs as a result of multiple cumulative impacts. Next, the simulation model is used to simulate and analyze the rotor's power and particle size distribution of crushed products of limestone, iron ore, and copper ore during crushing. The reliability of the simulation model is experimentally validated. Finally, the simulation analyzed the in-fluence of the diameter and speed of the crusher rotor, as well as the mixed feeding of various materials, on the rotor power and material crushing effect. The results show that the particle size distribution curves of three types of crushed products, including limestone, have a high degree of agreement between simulation and experiment. Fur-thermore, the simulation values of rotor power and specific power consumption fit well with the experimental values, verifying the reliability of the simulation model. As the rotor diameter and rotor speed increase, the rotor power and sand production rate gradually increase. And the increase in rotor power is much greater than the increase in sand production rate. When the feed is a mixture of multiple materials, the rotor power increases approximately linearly with the increase of the proportion of high hardness materials in the feed, while the yield of fine particles in the crushed product decreases with the increase of the proportion of high hardness materials in the feed.

This study investigates the susceptibility of two pipeline steels, ferritic–pearlitic CSN 12022 and martensitic L80, to hydrogen embrittlement. Electrolytic hydrogen charging increased the absorbed hydrogen content approximately fivefold in both steels, with the martensitic grade showing higher uptake due to its dense dislocation network and carbide distribution. Tensile tests demonstrated that hydrogen had little influence on yield or ultimate tensile strength but caused a severe reduction in ductility. Elongation dropped from 39 % to 13 % in CSN 12022 and from 25 % to 11 % in L80. Fractographic analysis confirmed a transition from ductile dimple fracture to quasi-cleavage fracture in the hydrogen-charged condition. These findings confirm that microstructure strongly affects hydrogen embrittlement: ferritic–pearlitic steel undergoes a more dramatic relative loss in ductility, while martensitic steel retains higher strength but exhibits significant hydrogen-assisted cracking. The results highlight the importance of considering hydrogen effects in the design and application of steels for energy and gas transport systems.

Monitoring and diagnostics of cutting tools are crucial for ensuring production efficiency and product quality in the machining industry. This study uses acoustic emission (AE) to non-invasively detect damage and monitor tool condition in real time. Experiments assessed cutting inserts in a milling head, both used and new. Results showed AE effectively diagnoses tool wear, with significant differences in signals from worn and new inserts. Fast Fourier Transform (FFT) analysis determined the frequency range of signals during machining, confirming AE's usefulness. Microscope verification supported the AE findings on tool wear. This research highlights AE's potential in non-destructive diagnostics, enhancing production efficiency and product quality

Cast iron with nodular graphite is one of the most important structural materials that exhibit really good mechanical properties already in the as-cast condition. Nowadays, cast iron with nodular graphite is used in many areas of the manufacturing industry, the most widespread being in the engineering and automotive industries. The applicability of this material for construction purposes is mainly due to its mechanical properties, which are close to those of steel, but the production cost of cast iron is lower. This experiment was aimed at optimizing the production of ductile iron castings in the casting pits so that the foundry could produce ductile iron castings in the casting pits. Therefore, the optimization of the moulding compound database material was carried out in numerical simulation and at the same time, the heat transfer measurement of the foundry sand mould was carried out.

The introduced work deals with the microscopic analysis of metallographically prepared selected metal materials structures, using a scanning electron microscope (SEM). Prepared samples of seamless steel pipes were subjected to a thorough microscopic examination from the outer surface to the inner regions in order to interpret the spe-cific structure, including the change of the inner surfaces due to wear. The experiment showed that the micro-structure and character of the surfaces play a crucial role in the behavior of metallic materials under real condi-tions. Four types of pipes were monitored according to their use. The unused steel pipe (designated as sample No. 1) exhibited a rough outer surface with identified inclusions, while the used pipe (designated as sample No. 2) showed marks of intergranular corrosion and significant wear after long-term use. The older pipe (designated as sample No. 3) showed a decarburized area and inclusions containing sulfides and aluminum. The steel pipe with corrosion layers (designated as sample No. 4) exhibited a continuous corrosion layer with cavitation and cracks. The results of this study offer a comprehensive view relating to the influence of the nature of the micro-structure and wear on the water flow (performance) of metal pipes, with an emphasis on the identification of possible risks associated with geometry change, corrosion and wear. The recommendations create a basis for predicting the degradation as well as appropriate maintenance to ensure their long and reliable service life under real-world conditions of use.

The push-type rotary steerable core bearing has high load capacity and high precision, and has been widely used in oil and gas drilling field. Its service life is difficult to predict due to various complex working conditions. Based on the finite element method, this paper establishes a three-dimensional rotating guide mandrel model to calculate and analyze the mechanical simulation of the guide mandrel under different working conditions, and establishes the corresponding life prediction model to predict its life. The results show that reducing the torque and speed in the range of drilling requirements is conducive to improving the overall life of the spindle, and the life matrix and life distribution are consistent with the characteristics of S-N curve, which is consistent with the characteristics of high cyclic stress of the spindle. The research results can be used to reliably predict the life of the push-type rotary steering mandrel and simulate its working state with high precision. This data is critical for reliability analysis and design optimization.

This study focuses on addressing the challenges faced by individuals with physical disabilities, particu-larly lower body impairments, by developing a stump socket using Reverse Engineering (RE), 3D Printing, and QFD. The integration of these three methods is something new in product design devel-opment, especially prosthetic products. The research adopted a three-step methodology: 3D scanning the stump, obtaining precise measurements, and fabricating a stump socket using fused deposition modeling (FDM) technology. QFD will produce technical requirements (TR) derived from consumer needs and brainstorming with prosthetists. TR will be the basis for developing the socket design in the 3D Scanning phase. The scanning process utilized Polycam, and the 3D models were refined with Meshmixer. The socket was fabricated using PLA+ material to ensure cost efficiency and customiza-bility. Experimental results demonstrated the accuracy and feasibility of the designed prosthetic sock-et, with a layer thickness of 0.2 mm and printing temperatures up to 215°C. The study highlights the potential of RE and 3D Printing to address the unique anthropometric variations of Indonesian users, overcome the limitations of conventional crutches, and reduce production costs compared to imported prostheses. This approach demonstrates a scalable and innovative solution to improve accessibility and quality of life for individuals with physical disabilities while contributing to economic inclusivity.

With the increase of hydro generators capacity and unit size, the requirement of lightweight is prominent. Taking a mixed-flow hydro generator as the research objects, the strength, the stiffness and the dynamic characteristics of upper bracket, stator frame, lower bracket and head cover have been simulated and analyzed by means of establishing their finite element models. Based on sizing optimization design method, plate thicknesses of the main parts were selected as the design variables, and strength and stiffness were taken as the constraint conditions to optimize them with the minimum mass as the objective function. Through lightweight optimization design, the maximum normal stress and maximum displacement of the optimized main parts are within the allowable value range, modal analysis shows that their dynamic characteristics meet the requirements. The lightweight optimization design reduced the weight of hydro generator by 3457kg in total. Optimization effect evaluation under full load operation and site test between the original and improved hydro generator set show that the dynamic characteristics are improved and the performances meet the design requirements.

The aim of the article was to present the results of cutting temperature measurements during trochoidal milling. The investigated material was 145Cr6 (50 HRC). Three trochoidal paths were used: A– described by movement circle, B– described by arcs and straight lines, C– described by short lines between a lot of points. The main conclusions include: similar values of cutting tem-peratures when using paths A and C (differences between the values of about 5%), the use of a trochoidal path type B enables a significant reduction of the cutting temperature. During tro-choidal milling, the maximum temperature values were about 420ºC.

This paper deals with the issue of selecting different machining parameters in the CAM system Siemens NX 1946. The issue of choosing between a solid end mill, milling cutter, and a high-feed tool when machining simple rectangular and rugged cavities concerning time and residual material is solved here. The chosen material was 1.1730, which is a basic material for the production of moulds without heat treatment. The paper deals with the issue of choosing the size of tool feed into the cut and its influence on the formation of the machining path depending on the depth of the cavity. The size of the residual material depends on the machining strategy and the choice of the plunge method into the material with regard to the total machining time. Performed simulations and experiments have shown a significant impact in individual settings and, thus, on the cost of machining components of such shapes.

Composite materials have consistently been applied in areas where a combination of properties such as strength, stiffness, and low weight is crucial. Motorcycle construction is no exception, as these parameters significantly impact riding characteristics, safety, and overall performance. This article focuses on quantifying the torsional and vertical stiffness of a single-sided swingarm made of carbon fiber reinforced polymer (CFRP) using finite element analysis (FEA) and verifying these results through experimental measurements. To enhance the accuracy of the simulations, which involve complex geometries and anisotropic materials, the material properties of selected fabrics used in the prototype production were measured. Specific fixtures were designed for the experimental measurements, enabling the application of torsional moments and vertical forces. Deformation under these loads was evaluated using the TRITOP photogrammetric system, which tracks deformations by monitoring the displacement of reference points under static load conditions and comparing them to a reference, unloaded state. Based on the acquired data, the overall stiffness values and their distribution along the length of the swingarm were calculated. The results showed a significant difference between simulation and reality. For the overall torsional stiffness, the simulated value was 249 N·m/°, while the measured was 270 N·m/°, showing a discrepancy of 7.7%. The vertical stiffness value from simulation was 414 N/mm, compared to 411 N/mm from experimental measurements, with a minimal difference of -0.7%. The stiffness distribution along the length of the swingarm exhibited a correlation, but with notable variation in certain areas. This confirms that accurately simulating CFRP parts with complex geometries is highly challenging, partly due to the sensitivity of the manufacturing process. Therefore, verification through experimental measurement is considered good practice.

There are many drawbacks and inconveniences in the application of human power in the energy meter calibration line. In order to achieve a standardized level of operation and to improve the efficiency and quality of the automated meter testing line, this paper applies the intelligent inspection robot to the automated meter testing line and discusses the key technologies involved. Based on the texture characteristics of the screws on the energy meter cover, a screw coordinate positioning method based on the texture center of gravity method is designed as a machine vision technique for intelligent inspection robots. Based on the feedforward controller transfer function and feedback system open-loop transfer function, combined with PI controller, a feedforward-feedback composite servo position control strategy is designed to complete the release action of the robot end controller. Pressure sensor on the robot end claw controller, integrated servo drive with current sensor. The Kalman filter method of static estimation is used to fuse and process multi-source data information to realize the grasping action of the robot end controller. The test results of the key technical performance and economic and time benefits of the robot show that the recognition success rate and grasping success rate of the robot for energy meters are as high as 100%, and it takes a total of 54s to complete each grasping and releasing action. The maximum error in each direction is 4.9mm, 5.2mm and 5.1mm respectively, and the maximum error in angle is only 1.25 degrees. The working manpower is reduced by as much as 93.16%, the average expenditure of inspection cost is only 1.24 yuan, and the floor space is reduced to 700 square meters. In summary, the study can ensure a high level of consistency in the quality of energy meters, improve the efficiency of calibration and production, and create greater economic benefits while providing a solid technical guarantee for the large-scale construction and stable and reliable operation of the power grid.

Parting-off stands as a fundamental method of turning, involving the cutting of the workpiece. The tool is most frequently a replaceable insert secured in a clamping bed. A pivotal set of observable metrics that ascertain the efficacy of a tool and its appropriateness for machining a specific material under defined cutting conditions is its durability. These durability parameters need to be determined for all new tools to ensure optimal performance and application in various machining scenarios. The primary objective of this research was analysis of the wear experienced by replaceable cutting inserts within the realm of parting technology. There were three distinct variants of replaceable cutting in-serts, all produced by esteemed manufacturer Dormer Pramet s.r.o. These cutting inserts were ap-plied in the parting process, consecutively machining two materials: bearing steel 100Cr6 and stainless steel 316L. The study not only encompasses the description of the cutting test procedure but also involves the meticulous execution of measurements and the subsequent analysis of the data procured from experimental activities. In the final phase of study, additional analyses are outlined to uncover the factors contributing to variations in certain obtained results. Those analyses, such as material or tool coatings analysis, provides more information about interplay between replaceable cutting inserts and the specific materials subjected to parting processes.

This paper deals with research of the heat treatment of tool steels Böhler K 455, K605 that are determined for production of tools for minting circulation coins. The aim of the research was to determine the impact of introduction of innovative heat treatment on the structural parameters and lifetime of coining dies. Experimental part presents the results of purity evaluation at semi-products with use of EDX analyse of the non-metallic inclusions, also microstructure evaluation, measurement of the size austenite grain after application of innovative heat treatment also. After ending of analysis and evaluation of lifetime coining dies, new parameters of heat treatment for using at the production were proposed.

Wire electrical discharge machining (WEDM) was employed to process thin-walled, multidirectional carbon fiber-reinforced silicon carbide (Cf-SiC) composites. This study investigates the effects of key WEDM parameters, including gap voltage (Vg), pulse on-time (Ton), pulse off-time (Toff), and wire electrode type on material removal rate (MRR) and surface roughness (SR). All experimental planning, data analysis, optimization, and result visualization were conducted using MATLAB software. Results indicate that using CuZn50-coated wire electrodes increases MRR by 11% compared to CuZn37 bare brass wire. Scanning electron microscopy (SEM) confirmed the inverse thermal expansion-based material removal mechanism, revealing surface defects such as fiber fractures, interfacial detachment, craters, and micro-cracks. Surface roughness, as indicated by 3D topographic measurements was found acceptable with an average Ra between 2 and 3 μm. Overall, WEDM proves effective for machining Cf-SiC, especially for complex geometries such as holes, grooves, keyways, and splines when appropriate electrodes and parameters are applied.

Based on the high hardness, poor thermal conductivity, and easy detachment of graphite in cast iron materials. Traditional rough machining inserts cannot achieve good machining surface quality, while the use of precision machining inserts results in rapid tool wear due to excessively sharp rake angles, limiting feed rates and reducing machining efficiency. In order to solve these problems, this paper proposes a method of cutting cast iron with coarse and wiper insert mixed cutting tools, aiming to improve the surface quality of machining and enhance machining efficiency. By studying the mecha-nism and cutting experiments of the wiper inserts, it was found that it improved the surface quality of cast iron and analyzed the reasons for tool wear. By controlling the integrity of the precision ma-chined surface of cast iron, the aim is to establish the basic theory and key technologies for the pre-cise and efficient manufacturing of high hardness materials. Improve the surface quality of cast iron processing, extend tool life, and improve processing efficiency.

This article deals with the modification of surface properties of austenitic steels using laser shock peening (LSP) technology. This technology introduces residual compressive stresses into the surface layer. These stresses improve the technical properties of the material not only by affecting the re-sistance of corrosion cracking under stress. The aim of the work was to influence the austenitic steel 08CHN10T by LSP technology, to perform a corrosion test in a boiling MgCl2 solution and the sub-sequent evaluation of these tests. Furthermore, the hardness was measured of the peened part of the material by LSP technology and unpeened part.