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Results 61 to 90 of 310:

Tensile Behaviour of Zn–Mg Heterostructured Materials for Biodegradable Implant Applications

Anna Boukalová, David Nečas, Drahomír Dvorský, Jan Šťovíček, Jan Pokorný, Jiří Kubásek

Manufacturing Technology 2025, 25(6):728-734 | DOI: 10.21062/mft.2025.078

Biodegradable zinc-based alloys have recently attracted attention as promising candidates for temporary implant applications due to their favourable corrosion behaviour and biocompatibility. In this study, three materials — pure Zn, Zn–1Mg alloy, and a Zn + Zn–1Mg composite — were fabricated via powder metallurgy and extrusion to evaluate their microstructural characteristics and tensile performance. The composite material was designed to combine ductile Zn regions with a reinforcing Zn–1Mg network, aiming to achieve a balance of strength and ductility. Microstructural analysis revealed coarse-grained Zn regions surrounded by ultrafine-grained Zn–1Mg areas containing Mg₂Zn₁₁ particles, with oxide shells present at the Zn/Zn–1Mg interfaces. Tensile testing showed improvement in mechanical performance compared to the individual constituents. However, the oxide shells prevented effective load transfer between the fine-grained and coarse-grained areas of the microstructure.

Optimization of Zero-Point Setting for Enhanced Measurement Accuracy

Miroslav Matuš, Mário Drbúl, Jaromír Markovič, Michal Šajgalík, Andrej Czán, Miroslav Cedzo, Richard Joch, Martin Novák, Jana Petru

Manufacturing Technology 2025, 25(1):95-102 | DOI: 10.21062/mft.2025.014

The precise setting of the zero point represents a critical factor in non-contact measurement of mechani-cal components, particularly in areas such as the engineering and automotive industries, where high accuracy is key to quality control. This study analyzes the impact of various alignment methods—specifically the best-fit method and the datum method (3–2–1)—on the measurement results of complex geometric shapes. Experimental measurements were conducted using a laser scanner and Polyworks 2015 software. The results indicate that the best-fit method achieves higher accuracy when measuring complex and freely oriented shapes, while the 3–2–1 method provides more consistent results for simply defined geometries. These findings confirm the importance of proper alignment method selection in op-timizing non-contact measurement processes and offer new insights for improving efficiency in industrial quality control.

Comparison of Bearing Surface Quality Parameters for Wind Turbines

Mariana Janeková, Daniela Koštialiková, Dana Bakošová, Andrej Dubec, Alžbeta Bakošová, Jana Králiková

Manufacturing Technology 2025, 25(3):297-306 | DOI: 10.21062/mft.2025.033

The thesis deals with the surface treatments of bearing steel processed for wind turbines, on which the quality parameters of the surface treatments performed were compared. This is blackening, which is a method of surface treatment that allows the protection of the base material from the negative effects of external influences, in particular from moisture and associated corrosion. The application of surface treatment by blackening contributes to a better and more efficient start-up of the bearing in service. In the experimental part, the individual results of the structural analysis carried out for all types of materials investigated are evaluated, with the analysis focusing on the structural properties, the quality of the adhesion properties and the influence on the service life of the machine components. Electron microscopy was used to investigate the structural properties of the layer as well as the base material, which allowed to obtain the necessary data to meet the objectives of this work.

Research on Optimization Design and Processing Technology of Engine Intake System Based on NX and Fluent

Jun Zhang, Ruqian Gao, Yangfang Wu

Manufacturing Technology 2025, 25(5):711-719 | DOI: 10.21062/mft.2025.066

To design an engine intake system that complies with FSC racing regulations while achieving enhanced operational stability, this study conducts a comprehensive review of domestic and international research advancements in racing engine intake systems. Through computational fluid dynamics simulations performed in Workbench Fluent, critical structural parameters of the restrictor valve were optimized, resulting in a 12.06% improvement in outlet mass flow rate compared to the baseline design. A three-dimensional parametric model of the racing intake system was developed using Siemens NX platform. Taking the intake plenum chamber as a representative component, this research systematically analyzes the CNC machining process for the mold of the pressure stabilization chamber. The investigation encompasses toolpath generation, cutting simulation verification, and ultimately implements the optimized NC program on machining centers for physical manufacturing. The fabricated mold exhibits high dimensional accuracy and superior surface finish, providing both theoretical guidance and practical manufacturing references for intake system development. This integrated approach combining numerical optimization with advanced manufacturing techniques demonstrates significant potential for performance enhancement in motorsport engineering applications.

Studies on a Robotised Process for Forging Steel Synchronizer Rings in the Context of Forging Tool Life

Artur Meller, Marcin Suszyński, Stanisław Legutko, Marek Trączyński, Vit Cernohlavek

Manufacturing Technology 2023, 23(1):88-98 | DOI: 10.21062/mft.2023.002

This paper proposes a solution not previously used in the forging industry, which aims to reduce the proportion of arduous human labour. The concept of a prototype robotic station for hot forging includes a system that allows the selection of batch material with its heating, the execution of the process of lu-brication of forging tools and the forging itself, synchronised with the feeding and removal of material using full automation, in accordance with the idea of Industry 4.0. At the same time, by increasing the repeatability of the entire forging process and changing some of its key parameters, it will be possible to influence the durability of the tools used during its implementation. In order to verify the impact of such a modified technological process on forging tool life, computer simulations of forging were performed, where the currently applied technology using hand forging was compared with a conceptual automated process.

Assessment of the Possibility of Using the Continuous Wavelet Transform and Fourier Transform to Analyse Geometric Structures Obtained on the Surface of Turned High-Molecular Polymers

Paweł Karolczak, Maciej Kowalski

Manufacturing Technology 2025, 25(1):24-36 | DOI: 10.21062/mft.2025.008

The article presents the possibilities of using wavelet transform and fast Fourier analysis (FFT) to evaluate the signal collected during roughness measurement. During the tests, high-density polyeth-ylene was turned using variable cutting parameters. During cutting, the tool feed was changed to ob-tain roughness structures of different types and with varying degrees of anisotropy. The measured roughness profiles were filtered with Daubechies 6 (db6), Morlet and "Mexican Hat" wavelets and examined using Fourier analysis. The research carried out shows how the machining conditions affect the surface condition and the stability of the cutting process under variable machining conditions for high molecular weight polymers. The effectiveness of the continuous wavelet transform (CWT), sup-plemented with data obtained from Fourier analysis, in identifying places and detecting the nature of disturbances in the generated roughness signal is also shown.

A Synthetic Geometric Performance Index for Parts Manufactured by VAT Photopolymerization

Valentina Vendittoli, Wilma Polini, Walter Michael Simon Josef, Giovanni Moroni

Manufacturing Technology 2025, 25(2):244-251 | DOI: 10.21062/mft.2025.028

Geometric deviations play a crucial role in the quality of additive manufacturing, particularly in parts made with biodegradable resins. Accurately controlling dimensional and geometric variations in manufactured components is critical for achieving defect-free production and meeting functional standards. However, defining a final quality score can be challenging due to numerous dimensional and geometric deviations associated with a part. An innovative metric for evaluating geometric performance was created to measure dimensional precision in components produced through VAT photopolymerization. The index measures the dimensional and geometrical deviations, revealing that external surfaces exhibit greater precision than internal ones. This difference is likely due to internal surfaces overcoming heat dissipation challenges during the cooling process, resulting in less shrinkage for external surfaces. This index is essential in various stages of the manufacturing process, including part design, design for manufacturing and assembly, quality assurance, and process planning, helping to select the appropriate additive manufacturing technology and optimal process parameters.

Study on Material Performance Calculation and Rolling Process Simulation of 35W210X Advanced High Strength Silicon Containing Steel

Tie Ye, Boran Chen, Zetian Li, Zhenyu Gao, Kuibo Liu, Zheng Ren

Manufacturing Technology 2025, 25(4):549-558 | DOI: 10.21062/mft.2025.055

This study used JMatPro software to comprehensively analyze the new low-iron-loss cold-rolled non-oriented high-grade electrical steel 35W210X, calculating phase composition, Gibbs free energy, stress-strain relationships, and yield strength changes. Results showed its ferritic structure and consistent calculated room-temperature yield strength with experiments. To study production cracks, JMatPro data was used in Deform-3D to simulate the five-pass reciprocating cold rolling on a Sendzimir 20-roll mill, successfully replicating the cracks. Aiming at the problems of frequent cracking and low yield rate (<50%), the study found the original single normalizing annealing process inadequate. Thus, an optimized double annealing process was adopted, controlling cracks and raising the yield rate to over 85%. This research offers theoretical and technological support for rolling high-silicon electrical steels like 35W210X.

Statistical Analysis and Machine Learning-based Modelling of Kerf width in CO2 Laser Cutting of PMMA

Ema Vasileska, Ognen Tuteski, Boban Kusigerski, Aleksandar Argilovski, Mite Tomov, Valentina Gecevska

Manufacturing Technology 2024, 24(6):960-968 | DOI: 10.21062/mft.2024.095

Recently, engineering polymers like PMMA have increasingly replaced traditional materials in industry where feasible, with CO2 laser cutting gaining attention for its high quality and speed in processing these materials. Achieving precise cuts is crucial for product accuracy, with kerf width serving as a key quality attribute to ensure quality and functionality of the final product. This study focuses on the im-pact of three critical process variables: stand-off distance, laser power, and cutting speed, on the kerf width in CO2 laser cutting of PMMA. Through a full-factorial experiment, the process parameters are systematically varied to understand their individual and interaction effects on the cutting process. The kerf width is measured as an indicator of precision using an optical microscope to evaluate the quality of the laser cuts. To address the non-linear relationships between these process parameters and kerf width, several machine learning models were utilized. Performance comparisons indicated that the Artificial Neural Network (ANN) model provided the highest accuracy, with R² values of 0.98 for the validation dataset and 0.95 for the testing dataset. The optimized ANN model offers a robust tool for parameter optimization, facilitating the determination of optimal settings to achieve the desired kerf width while ensuring productivity.

SEM Analysis of Surface Layers with Variable Ra Parameters for Tribological Optimization in Design Engineering

Paweł Knast, Jana Petrů, Stanislaw Legutko, Lubomir Soos, Marcela Pokusova

Manufacturing Technology 2025, 25(2):185-201 | DOI: 10.21062/mft.2025.022

In this study, the microstructure of surface layers with varying roughness (Ra parameters) was analyzed using scanning electron microscopy (SEM) to optimize tribological properties in engineering design. SEM revealed key microstructural features – sharp and mild protrusions, pitting, microcracks and contaminants – that were not available in traditional profilometry. Reducing the Ra value improved surface uniformity by reducing irregularities and defect lengths, which had a positive effect on tribological properties and surface durability. However, defects were still present even at Ra < 1.25 μm, indicating the "Law of Microstructural Roughness," which emphasizes the inevitability of surface irregularities despite minimizing roughness. The integration of SEM results with profilometric methods enabled comprehensive identification and assessment of defects, combining microstructure with tribological properties. Results suggest that controlled roughness is key in combining materials and optimizing functional surfaces, particularly in the aerospace, biomedical and automotive industries, where reliability under demanding operating conditions is a priority.

Fault Diagnosis of Electric Motor Rotor Systems Based on Feature Extraction and CNN-BiGRU-Attention

Mei Zhang, Zilong Sun, Wenchao Zheng

Manufacturing Technology 2025, 25(4):559-568 | DOI: 10.21062/mft.2025.048

To enhance the accuracy of fault diagnosis (FD) in motor rotor systems, this study introduces a novel method that leverages feature extraction (FE) combined with a CNN-BiGRU-Attention deep learning model. Initially, the time-domain features of the vibration signals are extracted using Variational Mode Decomposition (VMD), which also effectively denoises the data. Subsequently, the frequency-domain features of the vibration signals are extracted via Fast Fourier Transform (FFT). The aggregated features are then fed into the CNN-BiGRU-Attention model to perform fault classification. In this model, the Convolutional Neural Network (CNN) module extracts local spatial features, the Bidirectional Gated Recurrent Unit (BiGRU) module models the temporal dependencies, and the Attention mechanism enhances the focus on critical fault information, thereby improving the model's classification performance. Experimental results demonstrate that the proposed FD method achieves an accuracy of 99.58%. Compared to other commonly used models, the performance metrics of our model show significant advantages and superior performance.

Comparison and Verification of Stress Measurement Results Using the Barkhausen Effect during Three-Point Bending

Tomasz Domański, Wiesława Piekarska, Milan Saga, Zbigniew Saternus, Marcin Kubiak, Milan Vasko

Manufacturing Technology 2025, 25(6):751-757 | DOI: 10.21062/mft.2025.084

Non-destructive stress measurement techniques are extremely important and are still being developed in engineering research and diagnostics of materials. They allow for a quick assessment of their condition without damaging the structure. Their development is crucial for the safety of structures and extending the life of materials. One of the new methods is the measurement of stress using the Barkhausen effect. The MagStress 5d device was used for the tests. In this work, stress measurements were performed using the MagStress 5D device during three-point bending of a steel flat bar. The results were verified using resistance strain gauges and numerical simulation was performed in the Abaqus program. The measurements indicate that the MagStress 5d device using the Barkhausen effect can serve as a complete alternative to traditional extensometers. The results provided by the introduced method showed very good agreement with the latter.

Analysis and Optimization of Horizontal Centrifugal Casting Process for Thick Walled Alloy Layers in Tilting Pad Bearings

Ye Jun, Jin Jing, Wang Guobiao, Xu Zhaohui, Guo Huangsha

Manufacturing Technology 2025, 25(3):307-317 | DOI: 10.21062/mft.2025.034

The optimization of process parameters plays a critical role in controlling temperature and velocity fields during centrifugal casting, which is essential for mitigating shrinkage porosity defects caused by uneven cooling in thick walled bearing alloy layers. In this study, two sequential numerical models were devel-oped using ProCAST software to simulate gravity filling and centrifugal solidification stages. The effects of key parameters, including inlet cross-sectional area and centrifugal rotational speed, on flow field characteristics were systematically analyzed. By using an orthogonal experimental design, we deter-mined the optimal parameters: a melt temperature of 440 °C for the Babbitt alloy, an initial temperature of 280 °C for the bearing blank, a filling inlet diameter of 16 mm, and a rotational speed of 340 r/min. Bearing alloy layers manufactured according to these optimized parameters exhibit no evident shrinkage or cracks on their surfaces. The high quality finished products meet the design requirements, thereby validating the accuracy of the numerical simulation.

Strategy for Fabricating Tree-Like Branched Al-Al₂Cu Heterogeneous Nanostructures for Future Application in Battery Anodes

Elena Chochoľaková, Lucia Bajtošová, Nikoleta Štaffenová, Jan Hanuš, Peter Minárik, Miroslav Cieslar

Manufacturing Technology 2025, 25(5):589-596 | DOI: 10.21062/mft.2025.067

Tree-like branched Al-Al₂Cu heterogeneous nanostructures with a high surface area ratio were successfully fabricated using magnetron sputtering of Al matrix and Cu nanoparticles, followed by in situ annealing. The method enables precise control over the composition and morphology of the nanosized columnar Al₂Cu phase grown on the substrate and embedded in the Al matrix. The formation of Al₂Cu begins at the initial locations of sputtered Cu nanoparticles. Further annealing promotes their coalescence and coarsening. Orientation relationships examined in several Al₂Cu particles revealed a semi-coherency with the Al matrix. The high surface area and tunable composition highlight the potential of these nanostructures for advanced battery anodes, with tailored geometry achieved through controlled processing conditions.

Effect of Filler Content and Treatment on Mechanical Properties of Polyamide Composites Reinforced with Short Carbon Fibres Grafted with Nano-SiO₂

Dana Bakošová, Alžbeta Bakošová, Petra Dubcová, Daniela Koštialiková, Andrej Dubec, Mariana Janeková

Manufacturing Technology 2024, 24(4):521-531 | DOI: 10.21062/mft.2024.058

The polyamide PA6 composites reinforced with carbon fibres (CF) are widely studied due to their properties and their high strength to weight ratio. Good adhesion between a filler and a matrix is es-sential for enhancing properties of a resulting composite. This study investigates the effect of the short CF content and the used CF treatment on mechanical properties of the PA6-CF composites. The composites were subjected to tensile, flexural, compression, hardness and Charpy tests as well as dynamical mechanical analysis. An atomic force microscopy was employed to investigate topography of the CF and the composites. Initially, the properties of the composites were improved through the oxidation of the CF in HNO₃. Subsequently, to further enhance these properties, the oxidized CF were grafted with nano-SiO₂. The CF content in the tested composites varied from 10 wt% to 60 wt%. The most significant improvement of the tested properties was observed at the CF content of 40 wt%.

Advancing the ductile behaviour of heavy-wall API X70 pipeline steel by a “Slab/Sheet” thickness ratio increase

Vadym Zurnadzhy, Yuliia Chabak, Ivan Petryshynets, Alexey Efremenko, Ivan Sili, Ruslan Sagirov, Vasily Efremenko

Manufacturing Technology 2024, 24(5):843-854 | DOI: 10.21062/mft.2024.090

The present work was aimed at studying the effect of a “Slab/Sheet” thickness ratio (SSTR) on the microstructure and mechanical properties of API 5L X70 steel sheets intended for heavy-wall oil/gas pipelines. The 25 mm-thick and 40 mm-thick steel sheets were rolled from the cast slabs of different thicknesses (250 mm and 300 mm) and their mechanical properties were compared. The sheets were subjected to thermo-mechanical controlled processing followed by accelerating cooling, resulting in the structure of quasi-polygonal/acicular ferrite with minor amounts of granular pearlite and martensite-austenite constituents. Increasing the cast slab thickness significantly improved the ductility and low-temperature impact toughness of steel sheets regardless of their thickness. Specifically, a total elongation increased by 3-6 points (up to 26-28 %); an absorbed impact energy (tested at –20 °C) – in 1.5-1.8 times (up to 300-370 J); the DWTT shear area (at –20 °C) – in 1.6-2.1 times (up to 81-91.7 %). The properties advancement under SSTR increase was associated with an additional refinement of ferrite grains and better homogenization of cast structure under deeper hot deformation.

Research on Gradient Temperature Rolling Process and Deformation Uniformity of 10Ni5CrMoV Heavy Plate

Weiwei Wang, Baoshan Wang, Hongliang Zhang

Manufacturing Technology 2025, 25(2):265-272 | DOI: 10.21062/mft.2025.029

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.

Surface Morphology and Ablation Efficiency in DUV Ultrafast Laser Micromachining of Fused Silica

Jan Novotný, Libor Mrňa, Josef Sedlák, Štěpán Kolomý

Manufacturing Technology 2025, 25(4):521-530 | DOI: 10.21062/mft.2025.057

Fused silica is a key material for high-precision applications such as micro-optics and microfluidics. One route to improving direct laser writing (DLW) of fused silica is the use of shorter laser wavelengths, which enable tighter focusing and enhanced absorption. In this study, the influence of process parameters on surface quality and material removal during DLW using a deep ultraviolet (DUV) ultrafast laser (257 nm, 1 ps) was investigated. A full-factorial design of the experiment was used to identify conditions that optimise both surface quality and ablation efficiency. Surface roughness as low as Sa ≈ 200 nm and material removal rates up to 0.048 mm³∙min-1 were achieved. Conditions that led to surface degradation were also identified. Finally, the optimised parameters were applied to fabricate a microfluidic demonstrator. These results confirm that DUV ultrafast DLW is a powerful technique for fabricating high-fidelity features in fused silica with exceptional precision and quality that can be used for micro-optics or microfluidics devices.

Diagnostics of Milling Head Using Acoustic Emission

Paweł Piórkowski, Andrzej Roszkowski, Zofia Szabla

Manufacturing Technology 2025, 25(2):222-229 | DOI: 10.21062/mft.2025.023

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

Novel Multi Levels Tool Based on Rotating Ballizing Technique to Manufacturing the Externally Toothed Components an Experimental Study

Eman S. M. Abd-Elhalim, Emad A. Fahmy, Mohamed N. El-Sheikh, Ahmed M.I. Abu-Oqail, Hammad T. Elmetwally, Ayman Ali Abd-Eltwab

Manufacturing Technology 2025, 25(4):460-468 | DOI: 10.21062/mft.2025.049

Externally toothed components have a very crucial and essential role in all areas of production and manufacturing because they function as away of transmitting motion, energy, and power in all indus-trial applications, such asmodes of transportation, aviation, aerospace, equipment, and operating machines like lathes and milling. All machines have a gear box. Therefore, it is receiving increasing attention. This research presents a new multi-stage rotary ballizing technology for producing toothed parts in one stroke. This process has been investigated experimentally. The parameters that were ex-amined experimentally was at the optimal conditions for single stage ballizing were: die rotation speed of 315 rpm; Axial feed rate, 0.13, mm/rev; The interference (cross in-feed) between the balls and the tubular specimen of 5.5 and 6.5 mm is formed by three stages of ball forming of graduated outer diameters and fixed on a single mandrel; Initial tube thickness is 7 and 8 mm. The effect of these parameters on the forming load, filling ratio and quality of the formed part was studied. The finding sindicated that the seideal variables influence the forming load, tooth filling proportion, and product quality. Experimental results proved the success of this novel technique to form toothed tubular components

Innovative Design of a Transtibial Prosthetic Socket through Integration of QFD, Reverse Engineering, and 3D Printing

Rosnani Ginting, Aulia Ishak, Fadylla Ramadhani Putri Nasution, Rinaldi Silalahi

Manufacturing Technology 2025, 25(6):778-787 | DOI: 10.21062/mft.2025.085

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.

Observation of the Amount of Wear and the Microstructure of Hardfacing Layers after the Test of Resistance to Abrasive Wear

Miroslava Ťavodová, Miroslav Džupon, Monika Vargová, Dana Stančeková, Jozef Krilek

Manufacturing Technology 2024, 24(1):131-140 | DOI: 10.21062/mft.2024.003

The article deals with the evaluation of the amount of wear of the base material and selected hardfac-ing materials intended for tools for wood processing in forestry after a test of resistance to abrasive wear in laboratory conditions. The values of average weight loss Wh[g] and relative resistance to abrasive wear Ψh[-] were determined by calculation. The topography of the surface after the track of the rubber disc and the abrasive of the testing device was evaluated with a confocal microscope. The depth of the disc track Pt[μm;mm] was also evaluated with a confocal microscope. The state of the samples surface after the test, as well as the overall structure and mixing of the hardwearing material with the base material was evaluated by light microscopy. A touch roughness meter was used to de-termine the profile of the track surface after the test. Based on the results, we can recommend certain hardfacing materials for practice. Their abrasive resistance and thus also the loss of material during the work load could ensure a longer service life of the tool.

Analysis of Extrusion Process Parameters in PLA Filament Production for FFF Technology

Vojtech Senkerik, Martin Bednarik, Vaclav Janostik, Michaela Karhankova, Ales Mizera

Manufacturing Technology 2024, 24(2):265-271

Additive technologies are becoming a common part of not only prototype production, but also piece or small series production. However, the choice of technology and material plays a key role in the applicability of the manufactured parts. The most widespread type of additive technology is FFF technology, which consists of applying a fused plastic string in single layers. The resulting mechanical properties of parts produced using this technology depend not only on the material and structure selected, but also on the process parameters used in the printing process itself. This study deals with the production of filament from PLA, which is the primary material. The advantage is its environmental degradability after the end of the life cycle of PLA products. However, the resulting properties of the printed parts may depend on the way the filament is prepared and in particular on the melt temperature during filament extrusion. This study investigates the effect of the produced filaments on the quality of printed parts. It has been shown that the filament production technology has a significant effect on the quality of printed parts.

Numerical and Experimental Study into forming of the longitudinal Externally Spline Sleeves by internally rotary Ballizing Process

Ayman Ali Abd-Eltwab, Emad A. Fahmy, Mohamed N. El-Sheikh, Ahmed M.I. Abu-Oqail, Hammad T. Elmetwally, Eman S. M. Abd-Elhalim

Manufacturing Technology 2025, 25(6):758-770 | DOI: 10.21062/mft.2025.076

longitudinal externally splined parts have garnered increasing attention due to their critical role in power transmission across various industrial applications. This study explores the use of the internally rotating ballizing technique for manufacturing these components. The process was analyzed both experimentally and numerically through a mathematical model. The experimental investigation focused on key process parameters, including die rotational speed (50, 63, 80, 100, 125, 160, 200, 250, and 315 rpm), axial feed rate (0.13, 0.15, 0.18, and 0.21 mm/rev), interference between the balls and the tubular sample (cross in-feed: 2.5, 3.5, 4.5 and 5.5 mm), and initial tube thickness (4, 5, 6 and 7 mm). The study assessed the influence of these variables on the forming load and the quality of the produced longitudinal externally splined sleeves. A numerical model was developed to predict forming loads, and the findings indicated that these parameters significantly affect both (forming load and filling ratio). The optimal values for these variables were identified, and the numerical results showed a strong correlation with experimental findings. Keywords: Externally Splined Sleeves, rotary Ballizing Process, Numerical method, Experimental Study and forming load.

Experimental Measurement and Testing of 3D Printed Parts in Terms of the Material Used

Alexandr Fales, Vít Černohlávek, Marcin Suszynski, Jan Štěrba, Tomáš Zdráhal, David Nocar

Manufacturing Technology 2025, 25(2):174-184 | DOI: 10.21062/mft.2025.016

As part of my research work, in its practical part, I deal with the selection of suitable 3D printing pa-rameters for parts of a robotic kit, as well as the selection of a 3D printer and the determination of a set of experimental measurements and testing in order to obtain the necessary data to determine a suitable filament material for 3D printing of a part of a robotic kit and setting the appropriate 3D printing parameters to obtain the desired mechanical properties of the parts while maintaining the economic benefits of 3D printing. The main aspects for choosing a filament material are printability in primary and secondary school conditions, easy printing (beginner level), minimal postprocessing, adequate mechanical properties – these are obtained by experimental measurement and correspon-ding destructive tests on a real part from the VEX GO and IQ kit.

Thermal Analysis of Micro Plasma Wire Arc Additive Manufacturing Deposition Process

Siti Khairiyah Sulaiman, Mohd Rizal Alkahari, Mohd Juzaila Abd Latif, Yupiter Harangan Prasada Manurung, Keval Priapratama Prajadhiana

Manufacturing Technology 2025, 25(3):396-404 | DOI: 10.21062/mft.2025.039

Additive manufacturing (AM) is rapidly developing with emerging technology of wire arc additive manufacturing (WAAM) process due to its ability to manufacture large components and high deposition rate. However, WAAM faces mechanical properties problems like porosity, distortion, and strength due to the large heat affected zone (HAZ) from commonly used heat sources such as metal inert gas (MIG) and tungsten inert gas (TIG). Utilization of micro plasma as the heat source should reduce this problem since it has a smaller heat source diameter. Therefore, this study investigates the thermal distribution of micro plasma wire arc additive manufacturing (MPWAAM) by developing a finite element method (FEM) model. This paper focuses on the fabrication of single-layer multitrack deposition and tool path planning of multi-layer multitrack depositions by MPWAAM process. The melt pool size and peak temperature are mainly governed by heat input per unit travel speed of the worktable, with current and voltage being the significant factors. Besides, tool path planning strategy influences the properties and quality of the final product, where parallel tool path design with longer interlayer cooling time minimized part distortion and residual stresses.

Mechanical Alloying, an Innovative Way of Zinc Preparation for Biomaterial Preparation

David Nečas, Jan Blažek, Jan Pokorný, Anna Boukalová, Jiří Kubásek

Manufacturing Technology 2025, 25(5):662-669 | DOI: 10.21062/mft.2025.070

In this study, binary zinc-based alloys (Zn–1Mg, Zn–1Li, Zn–2Mn, wt.%) were synthesized by performing mechanical alloying (MA) of elemental powders, followed by consolidation using spark plasma sintering (SPS). The processing parameters were optimized to obtain homogeneous powders with controlled particle size. X-ray diffraction and SEM analyses confirmed the presence of secondary intermetallic phases (Mg2Zn11, Zn13Mn, ZnLi2 phases) formed during milling, which were preserved after SPS. Microstructural examination revealed a fine-grained microstructure with residual oxide networks originating from powder surfaces. Mechanical testing demonstrated significant strengthening effects after Mg and Li additions, with Zn–1Mg alloy reaching the highest hardness (128 HV1) and compressive strength (526.7 MPa), attributed to uniformly distributed Mg2Zn11 precipitates. However, this strengthening was accompanied by reduced ductility. Zn–1Li exhibited the most balanced combination of strength and plasticity, while Zn–2Mn provided only a limited improvement over pure zinc. These results confirm that mechanical alloying combined with SPS is a promising route for developing biodegradable Zn-based biomaterials with enhanced properties.

Microstructural Analysis, Corrosion Resistance, and Wear Performance Study of Al0.8FeCoNiCrCu0.5Si0.2 High-Entropy Alloy

Peng Zhang, Yanzhou Li

Manufacturing Technology 2024, 24(4):700-709 | DOI: 10.21062/mft.2024.062

The high-entropy alloy with the composition Al0.8FeCoNiCrCu0.5Si0.2 was produced through a pro-cess in-volving a vacuum arc melting method. Comprehensive characterization was performed through techniques such as XRD, SEM, and TEM. The findings revealed that the alloy primarily con-sists of Fe-Cr and Al-Ni phases, displaying predominantly two body-centered cubic structures. The alloy exhibited a characteristic dendritic cast structure. The alloy predominantly has high-angle grain boundaries accounting for 96.1%. Its grains demonstrate minimal internal strain and reduced lattice anomalies. The alloy showcased resistance with a corrosion current density of 1.4×10-7 A/cm2 and a corrosion potential of 0.28047 V. Post-corrosion examinations emphasized regions abundant in Al and Cu as the primary degradation sites. The addition of Si has further improved the alloy's resistance to corrosion. In terms of abrasion durability, the alloy exhibit-ed a wear scar length of only 1.42 mm, substantially less than the 1.88 mm found in 45# steel, highlighting its enhanced resistance to wear. This wear resistance is attributed to its inherent BCC1 and BCC2 phase structures and the hardness it derives from its unique composition. Owing to its superior traits, this high-entropy alloy presents promising potential for applications, including coatings, and advanced automotive components.

Determining the Force Required to Remove a Screw from a Human Vertebra

Patrik Balcar, Petr Vachata, Martin Svoboda, Jan Lodin, Michal Lattner, Antonín Svoboda, Edita Pichlová

Manufacturing Technology 2025, 25(6):721-727 | DOI: 10.21062/mft.2025.080

The article describes a pilot experiment of mechanical testing of 3D printed vertebrae with an inserted screw. The main goal of this work was to verify the design of a measurement methodology for experimentally determining the mechanical properties of vertebrae produced using 3D printing and also for determining the load-bearing capacity of a screw when it is drilled into a vertebra. The work describes the construction of a special fixture with which it is possible to clamp test samples for tensile testing. The stud screws were pulled out of a real or printed vertebra using a tearing machine. Testing was performed on porcine and 3D printed vertebrae. CT images of porcine spines obtained by a computed tomography scanner were used to create the printed vertebrae. This work verified the mechanical properties of printed and real vertebrae. In connection with this work, suitable printed materials and the necessary parameters of 3D printed samples will be sought so that they correspond to the necessary mechanical properties and can replace human vertebrae. It will then be possible to conduct laboratory investigations to obtain better results in spinal stabilization. The experiments verified the measurement methodology, compared the measured values between real and printed vertebrae, and also determined the next direction of research.

Investigation of the Wear Progression of Nozzle in Abrasive Waterjet Machining with Different Abrasive Material

Nuraini Lusi, Mebrahitom Gebremariam, Abdur-Rasheed Alao, Kushendarsyah Saptaji, Azmir Azhari

Manufacturing Technology 2025, 25(1):76-85 | DOI: 10.21062/mft.2025.011

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.

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