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The Influence of the Choice of Machining Strategy on Production TechnologyMartin Reznicek, Cyril HoravaManufacturing Technology 2024, 24(1):117-130 | DOI: 10.21062/mft.2024.014 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. |
Identification of the cause of damage to the firefighter ladderFilip Průša, Vít Jonák, Angelina Strakošová, Karel Doubrava, Miroslav Španiel, Václav Vystrčil, Dalibor VojtěchManufacturing Technology 2020, 20(4):500-506 | DOI: 10.21062/mft.2020.068 Two extendable firefighter ladders, both made of AA 6063 alloy, has been destructively tested accord-ingly to the ČSN EN ISO 1147 to determine the maximal load before their failure. For this purpose, two brand new ladders with a complex profile were compared to the 5-year old one with a far simpler profile. It was found, that the new ladder broke already at a load of 366 (365 kg) while the 5-year old ladder could withstand a much higher load of 426 kg. Since both the ladders broke nearby the guides acting as a mechanical support for their extension, it was of high interest to investigate the cause of different behaviour. Considering the fact, that the brand new ladder had a much more complex pro-file of the beam and the fact, that the guides were welded to the beams, it was of high importance to investigate the influence of the weld on the overall integrity of the ladder. It was found, that the weld itself deteriorated the mechanical properties of the beam reaching the minimal hardness in the dis-tance of 10 mm, which also corresponded with the crack initiation site. This place also showed the lowest hardness reaching only 52 HV 1. |
Dilatometric identification of bainitic transformation during Q-P processing of 42SiCr medium carbon steelŠtěpán Jeníček, Jiří Vrtáček, Ivan Vorel, Tomáš JandaManufacturing Technology 2020, 20(3):327-334 | DOI: 10.21062/mft.2020.057 Q-P process is one of the latest techniques for heat treatment of high-strength steels with increased silicon levels. It is believed to be based on diffusion and migration of carbon between martensite and untransformed austenite, where the latter becomes enriched with carbon, and therefore becomes thermodynamically stable. However, the question remains whether much of the carbon partitioning in the Q-P process might be the result of the competing bainitic transformation induced by arrested quenching below the Ms temperature. This paper explores the use of dilatometry for identifying the products of austenite decomposition during Q-P processing of medium-carbon 42SiCr low-alloy steel. |
Rapid Tube Hydroforming – The Innovative Casting-Forming Method for Rapid PrototypingAndrzej Kochański, Hanna SadłowskaManufacturing Technology 2020, 20(2):195-199 | DOI: 10.21062/mft.2020.039 In the recent years, the demand for weight reduction in modern vehicle construction has led to an increase in the application of hydroforming processes for production of automotive and aerospace lightweight components. The tube hydroforming measurement site (TH stand), designed and built at Warsaw University of Technology allows both die, and free tube hydroforming processes to be performed, thereby making it possible to obtain information about the material, as well as optimal process parameters [1][2]. The present freshly patented method for metal tube hydroforming is dedicated to short product series or even single products and prototypes [3]. The method is applicable to forming difficult-to-machine materials. The well-known techniques use dies made of plastic or wood, especially to form short product series. The use of moulding sand and properly prepared geometry of casting mould makes possible shaping materials at high temperatures, which could not be done in previous short series solutions, where a plastic or wooden die were used. [1] Sadłowska H., Jasiński C. Morawiński Ł., Strain measurements on the tube hydroforming testing machine, Archives of Metals and Metallurgy Vol. 65 , Issue 1, 2020, pp. 257-263 [2] Sadłowska H., Odkształcanie się rur podczas swobodnego rozpęczania hydromechanicznego na stanowisku TH, w: Prace Naukowe Politechniki Warszawskiej. Mechanika, Vol. 267, 2015, ss. 25-30 (in Polish) [3] Patent No. PL424401, Kochański A., Sadłowska H., Bulletin of the Patent Office of Inventions and Utility Models vol. 17_2019, pp. 11 |
Modification of a design of a wheel-tracked chassis of a mine clearing machineMiroslav Blatnický, Ján Dižo, Jozef HarušinecManufacturing Technology 2020, 20(3):286-292 | DOI: 10.21062/mft.2020.044 This article is aimed at design of a support and a tension mechanism to be mounted on a wheel-tracked chassis of a mine clearing machine. The subject machine serves to detect and disposal mines in terrain. The main advantage of this machine is the possibility to use it from the safe distance thanks a remote control. The wheel-tracked chassis mounted on the machine ensures that the machine is able to overcome extreme obstacles of a terrain. The solved design of the wheel-tracked chassis can be modifying to move using just wheels for better driving properties on metalled roads. Current design of the wheel-tracked chassis goes out from the older technical solution, which has been designed for a four-wheeled machine. The latest version of the chassis is designed for a six-wheeled machine. Application of an original structure of the chassis meets problems consisted in formation of ckacks in tracks struc-ture therefore the current structure of tracks has to be modified in order to meet all requirements in term of strength and long-term operation. At the same time, two design of a tension mechanism are presented. A tension mechanism is additional device, which will be mounted to the chassis and it will ensure the optimal position of tracks in every load case. |
Overall Equipment Effectiveness-related Assembly Pattern Catalogue based on Machine LearningPéter Dobra, János JósvaiManufacturing Technology 2023, 23(3):276-283 | DOI: 10.21062/mft.2023.036 Nowadays, a lot of data is generated in production and also in the domain of assembly, from which different patterns can be extracted using machine learning methods with the support of data mining. With the help of the revealed patterns, the assembly operations and processes can be further opti-mized, thus the profit achieved can be increased. This article attempts to explore the patterns related to the most used Key Performance Indicator (KPI) in manufacturing, the Overall Equipment Effec-tiveness (OEE) metric. The patterns and relationships discovered will be sorted into Assembly Pattern Catalogue (APC). Firstly, a literature review demonstrates scientific relevance. Secondly, it examines the circumstances and methods of samples in the Manufacturing Execution System (MES) data source and Enterprise Resource Planning (ERP) systems. In the third section, the detailed pattern catalogue is defined in the area of assembly. The novelty of the article is that beyond the generaliza-tion of patterns, it characterizes the pattern catalogue with mentioning practical industrial examples. |
Design and Algorithm Research of a Weight Sorting Transport RobotHaojie Du, Guang Yang, Lele PeiManufacturing Technology 2023, 23(6):967-975 | DOI: 10.21062/mft.2023.113 In warehousing logistics, the sorting and transportation efficiency of goods is still one of the important factors limiting the rapid development of logistics. At present, most regions still use manual sorting with low efficiency and high cost. Especially in some special work areas, such as high temperatures, severe electronic radiation, and areas with heavy long-term work tasks, urgent need for small robots to replace manual labor. In order to solve the inconvenience that small places such as logistics only use manual sorting, It is necessary to design a small-sized weight sorting and transportation robot, which can wait for receiving goods at a designated location, judge and identify the weight of goods by itself through PID intelligent control algorithm, which can move forward at a constant speed, and transport its weight to the designated position and unload it. Constant speed can make the trolley travel more smoothly and load and unload goods more smoothly, which is of great significance. |
Head Impacts during the Direct Frontal (Forehead) and Side (Temple) Collision – Human vs. Hybrid III DummyLubos Tomsovsky, Lucie Literova, Petr Kubovy, Frantisek Lopot, Martin Havlicek, Ondrej Stocek, Lukas Fara, Roman Jezdik, Hynek Purs, Tommi Tikkanen, Martin Novak, Karel JelenManufacturing Technology 2023, 23(5):717-724 | DOI: 10.21062/mft.2023.048 The paper is focused on the dynamic response of a Hybrid III crash-test dummy during low-severity frontal (forehead) and side (temple) head impacts. The measurements used a pedestrian dummy (Hybrid III 50th percentile male dummy, Jasti Co., ltd., Tokyo, Japan) and a unique pendulum impact testing machine (impactor) of own design and construction. The tests were conducted at two various impact intensities (velocities) that did not exceed the speed of 1.6 m.s-1. The primary outcome variable was a resultant magnitude of acceleration measured on the vertex of the dummy’s head and the results were compared to 11 human volunteers. The goal of the study was to analyze the biofidelity of the Hybrid III Dummy in a pedestrian setting during low-severity frontal and side head impacts by comparing the dynamics and kinematics of the dummy’s head to human volunteers. |
Method for Controlling Production Cost of Nano Ti-based Materials based on DMAICAobing Wang, Haiyan Zhang, Xin Li, Xin Zhang, Wenjing WangManufacturing Technology 2023, 23(3):354-365 | DOI: 10.21062/mft.2023.039 In order to reduce the production cost of nano titanium based functional materials, a production cost control method of nano titanium based functional materials based on DMAIC is proposed in this paper. The DMAIC (Define, Measure, Analyze, Improve, Control) model was used to analyze the production of nanoTi-based functional materials and define the main factors affecting the production cost of nanoTi-based functional materials. The indicators for measuring the quali. The regression model was established to determine the main factors affecting the rod content and yield of nanoTi-based functional materials. The appropriate experiments were used to determine the best control conditions and to improve the technical parameters. Through the control methods of monitoring, coordination and improvement, the phased results are consolidated and improved. The experimental results show that the quality and yield of nanoTi-based functional materials are significantly im-proved after using this method, and the cost reduction of each production link is also significantly higher than that of the comparison method. |
Development of Particulate Matter Monitors based on Light Scattering MethodJunjie Liu, Laihua Yu, Jing Ye, Zhihuang Huang, Jiazhen Lu, Yue LiuManufacturing Technology 2023, 23(6):989-998 | DOI: 10.21062/mft.2023.110 PM2.5 and PM10 measurement technique based on light scattering usually exhibit inaccurate measurement results in their applications. For improving the reliability of this method for PM2.5 and PM10 measurement, systematic research on the structure optimization of single particle light scattering sensors (SPLSS), calibration of SPLSS, and PM2.5/PM10 monitor development are carried out. Frist, by simulating and optimizing light scattering parameters, light scattering signals varied monotonically with particle size could be obtained, and thereby capability of accurate size-identifying can be established. Then, by developing threshold comparison circuit and calibration device, particle size channel of SPLSS or monitor could be divided, and particle counting efficiency could be corrected. Finally, by obtaining empirical values of parameters, i.e., heating temperature, particle density, involved in the developed dynamic heating system and PN-PM algorithm, interference of humidity and particle characteristics can be effectively eliminated, thus particle mass concentration (PM) could be calculated according to particle number concentration (PN) in each channel. The results show that the developed monitor has good accuracy by comparing it in atmospheric air with reference methods of PM2.5/PM10. |
Design of a Photoelectric Measuring Robot for Straightness of Deep/Blind Hole with Automatic Centering FunctionHaifeng ZhaoManufacturing Technology 2023, 23(5):739-749 | DOI: 10.21062/mft.2023.098 In order to quickly measure the straightness parameters of the deep hole/blind hole axis, a robot for measuring the straightness of the deep hole/blind hole axis based on the photoelectric prin-ciple is designed. Using the linearity of the laser as a reference, the straightness of the inner hole can be detected through the function that the PSD sensor can accurately locate the position of the energy center of the light. By studying the relationship between the position of the light spot and the output voltage of the PSD device, the measurement model of the straightness of the deep hole axis is derived. During the measurement, the robot spiral driving mechanism moves back and forth inside the deep/blind hole, and the automatic centering mechanism realizes the precise positioning of the deep/blind hole axis. The laser fixed on the axis of the automatic centering mechanism can illuminate the PSD target to obtain the current position data of the deep/blind hole axis. Use the least square median method to eliminate the gross error of the obtained data, and the least square principle fitting can obtain the measurement results of the current axis straightness. In order to ensure the measurement accuracy, the measuring robot is calibrated by a standard ring gauge and used for the age of the pipe with an inner diameter of 135mm to obtain an error accuracy of less than 0.05 mm for the axis. |
Computer Simulation of Heating Cycle of Aluminum Alloys Using Friction Stir Welding TechnologyPetra Kvasnová, Daniel Novák, Viktor Novák, Milan ĎurišManufacturing Technology 2023, 23(1):47-52 | DOI: 10.21062/mft.2023.014 The paper deals with welding of aluminum alloys using Friction Stir Welding technology. This repre-sents one of the solid-state welding technologies in which the base materials are not melted. This pro-vides new possibilities for the use of special and hybrid manufacturing technologies. The article presents the current progress in the Friction Stir Welding technology, a microstructure analysis of a weld joint created by the FSW method and a heat-deformation computer simulation of an aluminium alloy speci-men in the program Ansys. |
Research on the Application of Mirror Moulds for MasksWeiwen YeManufacturing Technology 2023, 23(6):1020-1030 | DOI: 10.21062/mft.2023.111 Precision mirror mould CNC machining is a technology of great importance in industrial manufacturing. Precision mirror moulds are usually used to produce high-precision, high-quality parts and products, which are widely used in automotive manufacturing, aerospace, electronic equipment and other industries. However, the traditional mould polishing process often fails to meet the manufacturing needs of precision moulds, so the application of CNC machining technology has become an effective way to solve this problem. Through the use of CNC machine tools and computer control systems, etc., the detailed formulation of the process plan, so that precision mirror mould CNC machining can achieve high efficiency, accuracy and stability of the machining process, to improve the quality and productivity of the mirror mould. Therefore, the applied research on CNC machining of precision mirror mould is of great significance and economic value. |
Experimental Investigation of Armour (Armox-Aramid-UHMWPE)Jindřich Viliš, Roman Vítek, Jan Zouhar, Michal Stejskal, Vlastimil NeumannManufacturing Technology 2023, 23(6):935-948 | DOI: 10.21062/mft.2023.083 In this study, the ballistic resistance of multi-layered composite armour is experimentally investigated. The composition of this armour consisted of armour steel Armox 500T, para-aramid fabric Twaron CT 747 and ultra-high molecular weight polyethylene Endumax Shield XF33. To compare the ballistic resistance, the ballistic resistance of the armour with the perforated steel Armox 500T was tested. The rifle cartridges 7.62 x 51 mm FMJ NATO M80 were used to test this resistance. The aim of this experiment was to compare the ballistic resistance of unperforated and perforated steel Armox 500T. As part of the experimental part, the chemical composition and microhardness of the steel Armox 500T was verified. The hardness of the composite materials was also measured for optimal armor configuration. After the projectile impact, the damage mechanism of the steel Armox 500T and the composite materials were investigated by using optical and electron microscopy. It was proved that the ballistic resistance of the perforated steel depends on the used pattern. Based on the performed experiments, the steel Armox with pattern A effectively reduced the weight of the testing configuration and absorbed all the kinetic energy of the projectile 7.62 mm FMJ M80. |
Effect of Milling Parameters on the Surface Roughness of SiCp/Al MaterialsLiang Wang, Yongqiang Pan, Xiaoxin ZhuManufacturing Technology 2023, 23(4):545-550 | DOI: 10.21062/mft.2023.063 The presence of reinforcing particles SiCp seriously affects the cutting surface quality of SiCp/Al materials.In this study, different machining parameters were tested to obtain good surface quality, and the surface quality of SiCp/Al alloy material under different milling parameters was studied by using the surface profilometer and scanning electron microscope to explore the effect of cutting pa-rameters on surface quality. The results showed that the Surface roughness value increased with the increase of feed rate and milling speed, and milling speed was the dominant factor in the microstruc-ture evolution of the machined surface. In addition, an exponential model related to feed rate and milling speed was constructed. |
Influence of the Mn Content on the Corrosion Behaviour of HEA CoCrFeN-iMnX (X=5, 20, 35 at.%) Prepared via MA+SPSFilip Průša, Petr Kratochvíl, Hana Thürlová, Darya Rudomilova, Šárka MsallamováManufacturing Technology 2023, 23(2):247-253 | DOI: 10.21062/mft.2023.016 The high entropy alloys with intended chemical compositions of CoCrFeNiMnX (X=5, 20 and 35 at.%) were prepared by the means of mechanical alloying. Prepared powders were then compacted using the progressive spark plasma sintering, which minimizes the deleterious microstructural coarsening. The compacts were, regardless of the actual chemical composition, composed of a solid solution with FCC crystallographic lattice and a small amount of carbides identified as Cr7C3. The dimensions of those carbides increased with the content of Mn, which was confirmed also by atomic force microscopy (AFM) and scanning kelvin probe microscopy (SKPM). The surface topography measured by AFM confirmed its presence as they emerged from the surface, perfectly matching the positive potential measured by the SKPM. It was found, that the HEAs are showing rather worse corrosion resistance in the aqueous environment containing 9 g/l NaCl compared to the reference 316L stainless steel. Moreover, the higher the content of Mn, the worse the corrosion resistance increasing the corrosion current density and shifting open circuit potential towards more negative values. When exposed to the elevated temperature of 600 °C, the alloys formed a poor protective oxidic layer that tended to chip off due to thermal stresses. |
Wear Analysis of Indexable Inserts after Machining of Austenitic Steel 1.4404Karel Sramhauser, Natasa Naprstkova, Iryna Hren, Frantisek Spalek, Tomas Vlach, Radim Kunes, Ondrej TupyManufacturing Technology 2023, 23(6):917-926 | DOI: 10.21062/mft.2023.094 This article deals with the comparison of the wear of indexable CNMG carbide inserts from two dif-ferent manufacturers when turning austenitic stainless steel 1.4404, which is not intended as the pri-mary material to be machined from the point of view of the tested inserts. The main goal was to demonstrate the different course of wear by testing inserts of the same type according to ISO 6987 showing the connection between the design and processing of the inserts in connection with the se-lected cutting parameters. The monitored type of wear was the main flank wear VBmax, depending on the length of the machining time. Optical and electron microscopes were used to analyze the flank wear. According to the assumption, it was found that the layout of the cutting edge geometry and coating layers has a noticeable effect on the degree of wear of the evaluated cutting inserts. At the same time, it was found that the tested indexable inserts achieved very good service life values de-spite the fact that the tested material does not belong to the primary use group. Evaluation of cutting tool wear has a significant economic potential for manufacturing companies seeking to minimize costs by trying to use as many universal cutting tools as possible or looking for opportunities to ex-pand the applications of already used cutting tools. |
Exploration and Realization about Teaching Experimental of CNC Machine Tool Based on Virtual Simulation TechnologyLifu Liu, Wei Li, Xuerui ChenManufacturing Technology 2023, 23(4):485-494 | DOI: 10.21062/mft.2023.066 In order to cultivate students' professional skills and enhance students' practical ability, this paper proposes to create a virtual simulation experiment system of NC machine tool based on SolidWorks software platform, taking vertical machining center as the research object, which is integrated by three modules of NC machine tool structure, machine tool operation and machine tool processing. Firstly, the detailed assembly relationship of each subsystem of the machine tool, the assembly rela-tionship of the overall equipment and the system composition are displayed intuitively by 3D modeling, so that students can understand the 3D modeling method and structure composition of complex CNC machine tools. Secondly, according to the machining process characteristics of vertical machining center, using typical parts to create the virtual simulation platform to carry out complex parts programming and machining methods and steps based on vertical machining center. Through the full combination of virtual simulation experiment and actual equipment, it has significant results in improving students' interest in learning, ensuring teaching effect, reducing material waste, avoiding machine tool accidents and so on. And combined with the actual processing, operation of CNC machine tool experiment to achieve the combination of virtual and real, vivid image, rigorous and realistic, open and sharing, expand the numerical control technology class teaching and talent training. It also provides a good reference for similar curriculum development. |
Geometric Accuracy of Components Manufactured by SLS Technology Regarding the Orientation of the Model during 3D PrintingMiroslav Matuš, Vladimír Bechný, Richard Joch, Mário Drbúl, Jozef Holubják, Andrej Czán, Martin Novák, Michal ŠajgalíkManufacturing Technology 2023, 23(2):233-240 | DOI: 10.21062/mft.2023.027 Selective Laser Sintering (SLS) or sintering of polymer powders is one of the most well-known additive technologies for printing 3D components. The properties of individual polymer powder materials have a significant impact on the quality of the manufactured part. Potential deformation and shrinkage can occur during printing if a significant number of parts are piled on top of one another or are oriented incorrectly, accumulating thermal energy in certain areas. The aforementioned research focuses on an experimental study to investigate the impact of the distribution and orientation of printing samples in the build chamber on the accuracy of dimensions and the surface roughness of PA12 prints. The aim of the study was to examine the impact of model settings during production as well as the effect of individual factors on the properties of manufactured parts, with a focus on ensuring that heat rises evenly from each print without accumulating. |
FEM Simulation of the Flange Turning in the Production of Aluminium Aerosol CansCsaba Felhő, István Sztankovics, Zsolt Maros, Krisztina Kun-BodnárManufacturing Technology 2023, 23(6):810-818 | DOI: 10.21062/mft.2023.104 Even today, there is an ever-increasing demand for the production of aerosol cans made of aluminium, as the cosmetics and other propellant-enriched products stored in them reach more and more people with the development of humanity. The production of these packaging materials is primarily carried out by plastic forming operations. However, during the production process of aluminium aerosol cans, tools with a defined edge geometry also perform cutting operations. The processes taking place here affect the quality of the final product. In this paper, the procedure and results of finite element modelling of the flange turning of aluminium aerosol cans is presented. The structure of the finite element model is introduced, as well as the possibilities of considering the peculiarities of the process. Since the used pure aluminium (Al99.5) is considered a difficult-to-cut material, the machinability of aluminium and its alloys is also discussed. |
Treatment of High-strength CFB-QP Forged Parts by Stepwise Water QuenchingŠtěpán Jeníček, Ivan Vorel, Michal PekovićManufacturing Technology 2019, 19(6):966-972 | DOI: 10.21062/ujep/404.2019/a/1213-2489/MT/19/6/966 The forging industry, and the production of high-strength forged parts in particular, saw no substantial progress in recent decades. High-strength parts continued to be made of well-tried steel grades which meet the economic and environmental production requirements, using mainly the conventional quenching and tempering. However, the latest findings in physical metallurgy of higher-silicon steels suggest that high-strength forgings can also be obtained by producing bainitic and martensitic microstructures. The first are of the CFB (carbide-free bainite) type and the latter comprise the QP (quenching-partitioning) microstructure. At greatly reduced processing costs, properties comparable to tempered martensite can thus be attained. |
Experimental and Numerical Modal Analysis of the Carbon Composite Plate Damaged by CutJán Vavro jr., Ján Vavro, Alena VavrováManufacturing Technology 2019, 19(5):891-895 | DOI: 10.21062/ujep/390.2019/a/1213-2489/MT/19/5/891 The given paper is closely connected with the experimental and numerical modal analysis of the carbon composite plate damaged by cut. In relation to the tested carbon composite, modal analysis was performed by help of special measuring device Pulse 12. The mentioned device was supplied by company Brüel & Kjear and the experimental measurements were carried out using damaged and undamaged plate sample which were prepared from the mentioned material hereinbefore. The investigated and analyzed plates of carbon composite were made of six layers of carbon fibres and they were arranged under the angle 90º (it is like fabric material made off carbon fibres). The layers arranged in the given way were joined by epoxide resin MGS 285. The experimental measurement of eigenfrequencies of carbon composite plates was carried out using the undamaged and damaged sample with proportions 78 mm x 78 mm while ten measurements were performed for each one specified site of the sample. In relation to the damaged plate sample, there was cut in length of 20 mm in the centre border. The finite element method in the software system ADINA v.8.6.2 was used for numerical analysis of the eigenfrequencies. |
Destructive and Non-destructive Assessment of the Thickness of Oxide Layers of Super-heater TubesJana Veselá, Pavel Mares, Petra BublikovaManufacturing Technology 2019, 19(1):161-167 | DOI: 10.21062/ujep/262.2019/a/1213-2489/MT/19/1/161 Tubes of super-heaters and heaters used in conventional power plants are exposed to coolant and high temperatures. The growing oxide layer on the inner surface reacts over time as a heat insulator on the water side and reduces heat transfer through the wall of the tube. A relatively thin oxide layer already contributes to the boiler efficiency and causes a permanent overheating of the tube wall. As a result of overheating at the site, the intercrystalline cracks leading to the bursting of the tube are developing. The secondary problem of the growth of oxide layer thickness is so-called exfoliation. For non-destructive evaluation of the thickness of the oxide layer directly at the power station, ultrasonic method (UT) can be used with a high frequency probe. In order to verify the accuracy of the measurement and the qualification of the ultrasonic testing methodology, light and Scanning Electron Microscopy (SEM) was used on specimens that were removed from the super-heater after the UT measurement. The standard longitudinal cut surface imaging in BackScatter Electrons (BSE) and Energy Dispersive Spectroscopy (EDS) analysis for accurate thickness determination with the chemical composition of the layer confirmed the accuracy of the UT measurement. |
Study on Ti2AlC/Mg Matrix Composites with Dual-scale Three-dimensional NetworkYujia Chen, Lai HuManufacturing Technology 2022, 22(5):519-529 | DOI: 10.21062/mft.2022.065 The development of metal structural materials with low density, high specific strength and large internal friction is extremely urgent for the development of lightweight, high speed and high power of equipment and railway. The properties, microstructure and the evolution of interfacial bonding of composite materials are closely related. In this paper, the microstructure of Ti2AlC/Mg matrix composites with double-scale three-dimensional network is mainly studied. The prepared composite material presents a three-dimensional network in macro-micro scale, and the matrix and reinforcement are connected with each other. The mechanical properties and damping properties of the prepared dual-scale three-dimensional network Ti2AlC/Mg matrix composites and magnesium alloy matrix were tested. At the same time, the equivalent modulus of three-dimensional network Ti2AlC/Mg matrix composites on microscopic scale is predicted by finite element method according to the basic properties of Ti2AlC ceramics and AZ91D. The following conclusions are drawn: the ultimate bending strength of the composite material is increased by about 10% compared with its matrix magnesium alloy, and its ability to maintain strength is greatly improved compared with the matrix. Using the extracted information, the equivalent modulus of the composite microscopic model is calculated to be 31.25734 GPa, which is consistent with the experimental results. It provides data and theoretical support for similar research. |
Application of Lean Six Sigma for Improve Productivity at The Mechanical Plant. A Case StudyMinh Ly Duc, Minh Nguyen ThuManufacturing Technology 2022, 22(2):124-138 | DOI: 10.21062/mft.2022.028 This study focuses on performing the analysis of manipulator operations on the machining line of precision mechanical products using the Human-Machine correlation analysis tool through images collected from the camera, wasteful operations incurred in machining according to Lean Six Sigma (LSS) standards to control fluctuations in the machining line, improving the overall productivity of the line (OEE). Specifically, contributing to improving productivity, quality, and competitiveness of the company in the market, create a good product image for consumers. This paper proposes a 7-step quality control (QC) cycle improvement model, called 10 step QC cycle. In step 5, use Man - Machine correlation analysis tool from video images to identify wasteful activities. In step 6, we propose a Direct Numerical Control (DNC) model to call the machining program for MC machines using a barcode system and a computer vision model for human identification at each processing line according to a controlled fixed layout. The right people have been trained enough to operate the line; the specific result is eliminating the occurrence of accidents in processing from 7 cases to none. A model of a product dimensioning system implemented for fully automated product quality control combined with redesigned machining jig with a vapor sensor system eliminating the reliance on human manipulation Specifically, the result from this improvement activity is the increase in productivity from 115 products per 8 hours to 155 products per 8 hours and the handling time has decreased from 1.3 hours per day to 0.36 hours per day (reduce 0.94 hours per day). The Partial Least Squares Structural Equation Modeling (PLS-SEM) is used to analyze the results of the survey of employees' opinions about the usefulness, convenience, and technical factors after the operation. The results from improvement activities show that user loyalty is highly appreciated in terms of usefulness and convenience. However, in terms of technical factors, it is still necessary to improve the quality of the information network system, the barcode scanning system and the quality of barcodes in the oil environment |
Rapid Determination of Changes in Material Properties of Water Turbines BladesMaxim Puchnin, Františka Pešlová, Jiří Kuchař, Viktor KrejbichManufacturing Technology 2022, 22(5):585-589 | DOI: 10.21062/mft.2022.075 The changes in the material properties of water turbine blades are characterized an undesirable process, which could lead to the end of usable life or to the emergency conditions of this turbine. For this reason, it is important to determine of any material quality changes and continuously monitor them. Considering that, these essential parameters are showing the ability of material to resist the operational stress. It is necessary to choose rapid methods of the material testing which are without preparation of the samples (it is inadmissible to the functional blades) able to immediately monitor the state of the materials by non-destructive methods. Due to mechanical stress and operational wear, the losses and damage occur in the water turbine blades, as the result, it leads to the deformation changes. This article is focused on the methodology of determination mechanical properties of corrosion-resistant steel, which is used on a large scale for the production of hydraulic elements and especially blades of water turbines. |
Research on Grinding Parameters of Parts with Same Clamping Mode and Different SizesHua Zhang, Hua Chen, Lai HuManufacturing Technology 2022, 22(3):377-383 | DOI: 10.21062/mft.2022.035 Aiming to study the influence of ultra-precision grinding parameters on the accuracy between the same clamping method and different workpiece sizes. This paper mainly analyzes the difference between the measurement precision of different parts by the same measurement method and the measurement precision of the same parts by different measurement methods. Therefore, the influence of grinding parameters on grinding precision is reflected. For the same part, it is concluded that the coaxiality error coincidence degree at end A and end B reaches 90.32% and 95.27%, respectively by using precision three-coordinate measuring instrument and Mahr roundness instrument. The coincidence degree of end A and end B verticality error reached 97.54% and 91.08%, respectively. For parts with different sizes, the Mahr roundness meter is used for measurement. The analysis shows that the coaxiality coincidence at end A and end B is the highest, reaching 98.36% and 92%, respectively. And from the analysis, the errors are mainly reflected in the factors such as jig and fixture and grinding process. |
Coating Surface Roughness Measurement Made On Coining DiesTomáš Hanes, Pavol Hvizdoš, Miroslava Ťavodová, Daniela Kalincová, Júlia Hricová, Pavel BeňoManufacturing Technology 2014, 14(3):309-317 | DOI: 10.21062/ujep/x.2014/a/1213-2489/MT/14/3/309 The paper describes the surface roughness measurement of functional parts of tools for minting coins. The coining dies were coated with three types of coatings - CrN, TiCrN and WC/C. Roughness of the coining die surface is a very important factor for the quality of a struck coin. The quality of specific coatings on the coining die surface was evaluated by a contact (Hommel Tester T500 roughness measurement device) and contactless method (microscope Sensofar PLu neox) by using optical interferometry and confocal microscopy. Results from the shop measurement gained by using the roughness measurement device were compared to the laboratory measurements gained by using microscope. Moreover, results were illustrated in the graph. Measured values were identical. Only the CrN coating showed bigger difference. Minimum roughness value was measured on the coining die with the TiCrN coating. The WC/C coating reached the maximum roughness value. 3D visualization method of surface roughness using software Gwyddion proved inappropriate for burnished surfaces. |
Analysis of the Welding Process of Steel Pistons of Internal Combustion EnginesPaweł ŻurawskiManufacturing Technology 2022, 22(4):494-509 | DOI: 10.21062/mft.2022.048 The aim of the article is to analyze the friction welding process of steel pistons, due to the small amount of scientific literature on this subject. First, it is necessary to present the design fea-tures of steel pistons and their advantages and disadvantages. Then analyze the types of friction weld-ing processes used in the production of pistons of internal combustion engines with the analysis of their differences. Present two basic methods of welding in the production of steel pistons, i.e. friction butt welding and low pressure friction welding. Finally, a proper analysis of the friction welding pro-cesses of steel pistons of internal combustion engines can be presented. At the end, the conclusions of the analysis are presented and proposals for improving the process are made. |
Relaxation of Polyvinyl Butyral Film with Non-uniform ThicknessAleš Mareška, Tereza Kordová, Martin Havlík MíkaManufacturing Technology 2022, 22(1):45-58 | DOI: 10.21062/mft.2022.010 Polyvinyl butyral is a material that is widely used in the manufacture of laminated glass sheets. Polyvinyl butyral film is widely used as an intermediate layer for laminated automotive or architectural glass. The intermediate layer primarily ensures the safety function of the laminated glass. Other advantages of laminated glass with a polyvinyl butyral interlayer include that it can be adapted to perform other functions, including acoustic functions, anti-reflection functions or functions enabling information to be projected on the glass with this interlayer. In this work, the influence of further processing of polyvinyl butyral film with non-uniform thickness is studied. Further processing may have a negative impact to the profile of PVB material. |


