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Atomic Diffusion Additive Manufacturing (ADAM) is a progressive layering process based on metallic materials with a plastic binder designed to extruse the material. The ADAM process can be classified as an indirect additive manufacturing process in which a solid fiber of metal powder enclosed in a plastic binder is applied. After creating a 3D object by the ADAM process, the excess plastic binder is removed in the cleaning chamber and vacuum sintering of the 3D object is performed. This work aims to provide a preliminary characterization of the ADAM process and compare the achieved results with the application most implemented so far in additive manufacturing for metal 3D objects using Selec-tive Laser Melting SLM. In particular, the density and microstructure of the applied process and mate-rial 17-4PH are studied, while optimal or recommended technological parameters of production facili-ties are applied. Furthermore, the dimensional accuracy of the ADAM process is observed, which is evaluated by means of IT accuracy levels according to the ISO reference artifact. Due to the applied AM process, the final character of a 3D object depends on technological parameters. The weight of a 3D object is low compared to the material processed by additive manufacturing processes in a powder bed. The dimensional accuracy and roughness of the surface depends on the geometry, orientation, and position of the individual shape specifications of the 3D object. Additive technologies generally achieve a degree of accuracy of approximately IT12 to IT13, which is comparable to traditional semi-finished metal manufacturing processes.

With the development of 3D technology, more and more materials are being used for manufacturing and used in many fields, such as factory manufacturing, workshop manufacturing, food packaging, and even architectural design and civil engineering design. In particular, the mechanical properties of the 3D printed HIPS polymer unit cell structure are worthy of research and analysis, providing more valuable references for future material development. This study focused on the properties of HIPS polymer materials and the performance of HIPS polymer 3D printed lattice structures after Instron instrument compression testing. The experimental samples were divided into 4 groups and there were 4 different experimental variables for analysis and comparison. Finally, it was found through analysis that the HIPS polymer material has good compression resistance, and the structure is relatively stable. It can be used more in the fields of manufacturing, architectural design and civil engineering in the future.

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.

This study centers on 7B50 aluminium alloy. The intention is to reduce the pre-treatment and post-treatment times of the shot peening model. By comparing and analyzing different process parameters, the best combination of peening solutions can be obtained. The pre-processing is implemented through a GUI interactive interface. Post-processing is carried out by using Python for secondary development in ABAQUS. Orthogonal test method is employed for post-processing analysis of shot peening simulations under various process conditions. The results are evaluated by using a weighted composite scoring method to determine the depth of the residual compressive stress layer on the workpiece surface, the surface residual compressive stress, and the extreme deviation of the maximum residual compressive stress value after shot peening. The combined influence degree of shot peening process parameters such as impact speed, projectile diameter and impact angle is determined. The optimal combination of shot peening process parameters is analyzed and verified through simulation.

The development and characterizing of thin layers of AgCu, Cu, Ti, and Zr on nylon filters using PVD magnetron sputtering technology was conducted. The evaluation of these thin layers was mainly focused on characterizing specific parameters that may influence the expected functionality of the modified filter materials. The surface treatment of nylon filters with thin layers does not significantly affect the mechanical properties of the original nylon material. Thin layers deposited at a power of 0.9 kW exhibited greater thickness and lower static friction coefficient values than the layers deposited at 0.4 kW, except for a thin layer of the element titanium. The surface modification of the filters did not significantly change resistance to deformation and had no significant reduction in pore size. However, a significant effect on surface wettability (increased hydrophobicity) was demonstrated.

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.

Today's manufacturing industry, especially in the context of the metals industry, is constantly evolving towards ever more advanced technologies and efficient production practices. In this context, machinery modernization is becoming a key element in improving manufacturing processes. This article focuses on analysing the impact of machinery modernization on casting quality, using selected quality manage-ment tools. The article presents an analysis of the effects of the implementation of modern technology, automatic casting machines, on the quality of castings production. Using quality tools such as the Ishi-kawa diagram, Pareto-Lorenz and the FMEA method, the main causes of casting nonconformities, the frequency of occurrence of these nonconformities and the risks associated with them were identified for periods before and after the implementation of machine park modernization. The measurable benefits associated with the introduction of modern foundry technology in terms of improved casting quality were showed. Using quality tools, the quality improvement achieved was determined indirectly, while the level of improvement in casting quality after the modernization of the machine park was showed directly using the defect rate. It was also shown that, despite an increase in production efficiency and the level of quality of the manufactured products, the introduction of the new technology generated new quality challenges in the context of maintaining the stability of the casting process parameters as a result of a jump in productivity levels. The paper highlights the need to balance production efficiency with atten-tion to casting quality, which was an important issue for the foundry studied.

This research focused on the production of brake pads reinforced with bronze fibers to see the anticipated performance principles for braking systems. Three unique amalgamated formulations, labeled BRZ-I, BRZ-II, and BRZ-III, were set by varying the bronze fiber content to 5%, 10%, and 15% by weight. The tribological characteristics of these composites were systematically evaluated to determine their effectiveness. Traditional manufacturing processes were used in developing the brake pad. Various properties such as physical, chemical, mechanical and tribological possessions were assessed by means of chase test rig. Worn-superficial examination stayed carried out by using chase test rig. Base results it was evident that the 10 weight percentages of the bronze fibers showed better physical, chemical, mechanical and tribological properties. Chase test results confirmed that the composite brake pad developed with 10 weight percentages of bronze showed better results at higher pressure-speed conditions than others due to better plateau formation and less wear rate. The results obtained after performing various performances such as physical, chemical, mechanical and tribological properties concluded that the bronze fiber possessed lesser wear and stable coefficient of friction.

The materials used in VVER nuclear power plants are subject to thermal ageing in operation, among other degradation mechanisms. The aim of the experiment was to verify the effect of thermal ageing on the change of ultrasound velocity on the extracted parts of main circulation piping and pressurizer surge line made of austenitic steels. Two steel conditions were evaluated, as received and thermally aged. The research was carried out on samples made from non-operated pipelines and samples from pipelines after 28 years of operation. The samples were subjected to thermal ageing at 450 °C in an atmospheric furnace with a specified exposure time to simulate extended operation of the compo-nent for 60 years, where 1 year of operation means 10 months at 100 %-unit power and 2 months in shutdown. The samples were subjected to ultrasonic property measurements and the longitudinal and transverse wave velocities obtained are further used to calculate the Poisson's constant and elastic modulus E of the material. To verify the ultrasonic measurements, the samples were also subjected to mechanical tests to verify the changes in the mechanical properties in terms of elastic behaviour of the selected steels when subjected to a static 3-point flexural test and Electron backscatter diffraction analysis (EBSD).

In this study, the process parameters of a vertical shaft impact (VSI) crusher are optimized. Different feed size distributions, material physical properties, and product size distribution requirements are considered to determine the optimal material particle bond cleavage ratio. First, a numerical model is developed to simulate the crushing effect by adopting a CFD-DEM method. Then, the relationship between the crushing effect and the rotor speed, feed size distribution, and feed rate is revealed by analyzing the bond cleavage ratio of smaller-size distribution feed crushing to the specified particle size. The optimized working parameters of the crusher are determined under different feed size distributions. The results show that the feed size distribution of 8 mm, 20 mm, and 40 mm account for 20%, 30%, and 50% of the feed, respectively. Based on the results, it is implied that a feed rate of 120 t/h and a rotor rotational speed of 1800 r/min can be selected for crushing production. When the feed size distribution varies, this method can also be used to select a suitable feed rate and the rotor speed for crushing production. Overall, this study guides for optimizing the working parameters and improving the crushing efficiency.

The paper is a further step in ongoing research on the incorporation of the proposed bulk material rotary valve assembly into an existing production line serving the food industry in bagging milk powder. The main objective of the present paper is the strength static analysis of the previously presented structural design of the trolley and attachment of the frame structure as a track for the travel. Moreover, analytical engineering calculations whose results provide boundary conditions for the numerical strength design of the assembly of the rotary valve for transporting of bulk materials are included in the paper. The pro-posed mechanism allows precise manipulation of the rotary valve, especially at the time when it is nec-essary to clean the pipe connected to the rotary valve. Such manipulation is currently actual because of increasing the safety of maintenance of machines and equipment as well as because of reducing the physical burden of maintenance workers. The results of the analyses demonstrate the suitability of the design and provide a basis for further research in this area. The results discovered will be implemented in the form of additional boundary conditions in the numerical analyses of the frame itself carrying the whole travel of the trolley with the rotary valve (the frame forms the track for the trolley travel). The aim of the research is to reach a condition where the entire structure is safe for the operator during mainte-nance as well as for its surroundings during normal operation.

To enhance the effective penetration of cutting fluid into the depth of the cutting joint, a nano-cutting liquid atomization method has been proposed to improve the cutting quality of diamond wire sawing. A six-inch large diameter silicon wafer (150 mm diameter) diamond wire saw cutting experimental platform was constructed. The base liquid, nano SiO2, and nano SiC cutting liquid were utilized as the cutting fluids, and various cutting solutions were employed to compare the cutting quality of large diameter silicon wafers. The temperature field change, surface roughness of the silicon wafer, surface morphology, and warping of the silicon wafer were measured as evaluation indexes, and the impact law of different cutting solutions on the cutting quality of diamond wire saw was analyzed. The results indicate that nano-cutting fluid can reduce the roughness of silicon wafers and improve the surface morphology of silicon wafers. Mixing multiple nanoparticles can produce cutting fluids that further enhance wire saw cutting performance in actual diamond wire saw cutting technologies.

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.

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.

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.

Due to their availability and ease of use, additive techniques are experiencing dynamic development. This applies to both the industrial sector and individual recipients. The authors of numerous publications address in their research the subject of the influence of selected printing process parameters on the strength of models, usually made using selected MEX (Material Extrusion) methods. Among the MEX methods, the most frequently chosen are the FFF (Fused Filament Fabrication) and FDM (Fused Deposition Modeling) methods. This is due to the high availability and low cost of devices using the methods mentioned above and the high availability of polymer materials. In their research, the authors increasingly consider the influence of the internal structure of the samples and their density on selected strength parameters, often without considering whether they affect the geometric accuracy of sample mapping. For the above reasons, it was decided in the article to conduct research covering the indicated subject using the example of standardized samples made of six selected polymers used in the FFF method.

The article focuses on technological procedures of coating of metal molds made from Al-Si alloys, espe-cially used for making tyres. The idea is to create coating on aluminium based metal molds in order to reach a higher number of production cycles between individual cleaning operations in tyre making tech-nology. The experiment was based on a preparation of experimental samples, which were coated with a teflon based product with the addition of nanoparticles (eg. TiO2), in other words, particles as large as tens of nanometres, which were mixed into the teflon solution in a particular concentration. After creat-ing the coating, the experimental samples were put under a thermal load in various thermal modes. Fu-thermore, roughness, coating resistance, and changes after the thermal load were subjects of the study.

Variable Polarity Plasma Arc-Metal Inert Gas (VPPA-MIG) welding process is a new hybrid welding process with broad application prospects for aluminum alloy structure in the fields of aerospace manufacturing, transportation and others. The heat source of the hybrid welding process is composed of VPPA heat source and MIG heat source. When the total input energy of VPPA-MIG hybrid heat source is constant, the different energy ratio of VPPA arc and MIG arc affects not only the forming effect of hybrid weld, but also the stress distribution of hybrid welding joint. Hole-drilling method was used to analyze the influence of the ratio of VPPA and MIG arc energy on the distribution of welding residual stress in the process of 10 mm 7A52 aluminum alloy VPPA-MIG hybrid welding. The results show that the peak magnitude of hybrid welding residual stress increases with the increase of the ratio of VPPA arc energy. Considering the appearance of weld forming, VPPA-MIG hybrid welding parameters of 7A52 aluminum alloy are optimized on the basis of the distribution characteristic of residual stress. When the ratio of VPPA arc energy is selected between 35% and 40%, the peak magnitude of transverse residual stress is (in the direction vertical to the weld) no more than 92.0 MPa, and the peak magnitude of longitudinal residual stress(in the direction parallel to the weld) is no more than 234.3 MPa. It shows that the VPPA-MIG hybrid welding with optimized parameters can not only produce weld joint with satisfied macroscopic appearance, but also avoid high peak magnitude of residual stress.

A number of asset management models, methodologies and tools are available and well known today. How-ever, various organizational approaches to asset management processes are adopted by companies in the industry. In the paper, a number of examples of maintenance process models are summarized and a comparison of examples (benchmark) of real maintenance organizational structures is presented. The used examples origin from chemical, petrochemical and automotive industries. On this background, a case study of major maintenance organization change in Unipetrol, a central European refinery and petrochemical group (part of PKN Orlen) is presented and analysed. The goal of the implemented changes in the company was to increase the overall efficiency of the maintenance organization, mainly in the areas of management, and to achieve the set KPIs. Organizational changes were implemented on the basis of a model of a close connection between maintenance and production organizations in the form of a Multi-profession production team, named “Facility team”. The changes in the organisational structure and asset management processes described in the paper had finally a significant impact on the number of management positions (reduction by 25%), roles, competencies and asset management process flow. The quantitative impacts to KPIs in areas fulfilment of process safety requirements and efficiency, after implementation this changes, it had a positive effect in the horizon of the coming year and are also evaluated and analyzed in the paper.

The continuous development of thin coatings for different applications and using various coating meth-ods require the characterization of these newly formed surfaces to evaluate their utility properties. Binary thin coatings of titanium (TiN) and zirconium (ZrN) nitrides were prepared using the Arc-PVD (Ca-thodic Arc Deposition) method. Differences were observed in the structure and morphology of the thin coatings and the change in tribological properties at room and elevated temperatures (150 °C and 300 °C). The research is focused on evaluating the frictional properties of the coating using the Ball-on-Disc method in the dry friction mode. The emphasis is placed on the resistance of the thin coating to wear. The nanohardness was measured to be 26.2 GPa for TiN and 24.8 GPa for ZrN. Index of resistivity against plastic deformation H³/E² (plastic deformation resistance) for ZrN coating – 0.087 and TiN coating – 0.095, H/E (plasticity index) for ZrN – 0.059 and TiN – 0.060. Better friction properties and wear resistance (at 150 °C) were found for the TiN coating compared to the ZrN coating.

In the present study, an innovative method is proposed to improve the accuracy of thermal models of the grinding process. To this end, a set of orthogonal experiments are carried out to calculate heat flux using infrared temperature measurements. Then the convective heat transfer coefficient is modified based on the heat transfer and hydrodynamics theories. Finally, the modified heat flux and convective heat transfer coefficient are applied and a thermal model is established using ANSYS software. To verify the accuracy of the proposed model, a finite element grinding residual stress model based on the grinding heat and grinding force is established. By measuring the grinding residual stress and comparing it with the finite element residual stress model, the effectiveness of the grinding thermal model is indirectly verified. The obtained results demonstrate that the modified grinding thermal models are accurate and can be applied in engineering applications.

Surface integrity plays an important role in the functional performance of mechanical components and is one of the most particular consumer requirements in machined parts. Customarily, surface roughness is considered to be the principal parameter in evaluating surface integrity and surface quality on machined parts and has a significant effect on service reliability and component durability. It is dependent on a large number of machining parameters, such as tool geometry (i.e. nose radius, edge geometry, rake angle, etc.) and cutting conditions (feed, cutting speed, depth of cut). The effects of these parameters have not however been adequately quantified. So in order to identify the optimum combination of cutting conditions corresponding to better roughness, accurate predictive models for surface roughness must, as a first step, be constructed. An investigation in this regard has been conducted to address the surface integrity optimisation and prediction issue by applying the polynomial regression method for a variety of experiments and cutting conditions. A higher correlation coefficient (R?) was obtained with a cubic regression model, which had a value of 0.9480 for Ra. The use of the response surface optimisation and composite desirability show that the optimal set of machining parameters values are (250m/min, 0.2398 mm/rev and 2.3383 mm) for cutting speed, feed and depth of cut, respectively. The optimised surface roughness parameter and productivity are Ra =2.7567 ?m and Q = 95.341*103 mm3/ min, respectively. Results show that the models developed can accurately predict the roughness on the basis of measured cutting conditions as input parameters, and can also be used to control the surface roughness by making a comparison between measured and estimated values. Furthermore, operators can benefit from the proposed models if the aim is the reverse determination of the cutting conditions corresponding to the requested roughness profile.

The use of lathe chucks in machine building companies is the result of a great deal of work and the develop-ment of technical thought. Due to the progress and the possibility of increasing efficiency and at the same time relieving people from work that requires a lot of effort, especially physical effort, the use of better and more efficient production methods is a target that should be pursued nowadays. In the manufacturing pro-cess, these objectives can be achieved with the use of dedicated equipment. The following work will present an example of a lathe chuck specialized in turning operations. The aim of the work was to use a universal chuck as a base for designing and manufacturing a specialized chuck so that it is possible to mount rope wheels with diameters from 240 to 580 mm. This would eliminate the necessity of time-consuming changeo-vers. In addition, it is assumed that the handle must meet the conditions imposed by the limited number of tools and the working dimensions of the machine. The machining process itself was also important, where the most advantageous solution was to perform most of the operations in one clamping.

Research on efficient machining of hardened surfaces is invariably of interest because the number of wear resistant surfaces on the machined parts is increasing. These surfaces can be machined by both single-point (cutting) and abrasive (grinding) tools. However, in designating the finishing of the parts, the working characteristics of the products that the parts are intended for limit the finishing options. In this paper the results of a comparative experiment are introduced. In the experiments the allowances were removed from the hardened surfaces of the parts by turning, grinding or a combina-tion of them. The comparative analyses were carried out for the roughness and accuracy of the ma-chined surfaces and the procedures were assessed.

The aim of this paper is an analysis of the dependability of critical components of the John Deer 7530 tractor. For this analysis data was used from a database which contains maintenance data of 166 trac-tors during approx 9 years. The first part of this article is devoted to the selection of critical compo-nents based on number of failures of individual machine parts for a given period and their sales pric-es. The next part of article presents data for calculation dependability indicators which contains oper-ating times to failure and operating times without failure. Due to the large size of the data files of the individual components, the data are only given for one machine component. Furthermore, the meth-od of calculation of dependability indicators is described by parametric statistical methods according to ČSN EN 61649:2009 and mean time to operating failure. The results of the analysis are summa-rized in tables and graphs. The method in this article can be used to optimise the maintenance pro-gram.

With the rapid development of science and technology, the means of industrial production have become more diversified and intelligent, and the development of new means of industrial production has become an increasingly important research topic. Therefore, the automatic assembly technology was studied taking machine vision system as the main research subject in this study. An automated assembly model of industrial technology based on machine vision recognition was established, parameters such as the part positioning parameter, assembly time, the number of parts wrongly assembled and the number of parts missing and the qualification rate of assembly were obtained, and the corresponding experimental conclusions were obtained. Moreover it was compared with the traditional manual assembly technology, and it was found that the automatic assembly technology based on machine vision recognition had better performance and more remarkable experimental results compared with the traditional manual assembly technology, and the traditional manual assembly technology needed continuous modification and optimization. This work provides a new route for automatic assembly technology in industrial technology.

There are a number of methods for measuring propeller pitch but it could be a problem for many fishing boat builders who lack of professional equipment. This paper presents a method of propeller pitch measuring based on photogrammetry and CAD (Computer Aided Design). This method con-sists of three stages. At first, a series of photos of the propeller were taken by a smart phone. After that, these 2D images were processed by a photogrammetry software to create the 3D virtual model of the propeller. Finally, in CAD environment, the pitch at different radii of each blade of the 3D vir-tual model were measured. To validate the proposed method, several propellers for fishing boats were measured and the measuring results were compared to those archived by using an EDM (Electrical Discharge Machining) machine and by a highly skilled man with simple tools. The measurement results show that the proposed method could be acceptable for measuring pitches of propellers of fishing boats.

This paper provides an overview of the commonly used processes and equipment for laser cladding, including pre-set powder feeding, simultaneous powder feeding, wire feeding cladding, and coaxial cladding nozzles. By comparing the above processes and related nozzles, the coating characteristics are summarized for the selection of appropriate methods and equipment in different working environments. Meanwhile, the morphology and properties of the clad layers of shaft parts processed with different process parameters (e.g. laser power, scanning speed, lap rate, powder feed rate) and the influence of the combined parameters are overviewed. The changes and mechanisms of metals, ceramics, and metal-ceramic composites in terms of hardness, wear resistance, metallurgical bonding, and microstructure are analyzed. In addition, the application of numerical simulation techniques to simulate the temperature and stress fields and to plan the melting trajectory when laser cladding processing is performed on the surface of shaft parts are reviewed. Finally, the problems in the current research on laser cladding of shaft parts are summarized and the development directions are discussed.

This paper introduces a customized Fused Filament Fabrication (FFF) printer, featuring an advanced electromechanical system that achieves a substantial 500% increase in printing speed compared to con-ventional FFF printers. This research scrutinizes the printer's capabilities, emphasizing the dimension-al accuracy. Specifically, this study focuses on the investigation of the effect of high printing speeds on the dimensional accuracy of linear artifacts. The material selected is Acrylonitrile Butadiene Styrene (ABS) and the FFF-fabricated parts are designed and measured based on the ISO ASTM 52902-2021 standard. Last but not least, statistical analysis and comments are following, showing remarkable re-sults on such high-speeds.

The work aims to present a design method of cam five-bar paper taking mechanism of packaging machine based on position and orientation constraints to better meet the position and orientation requirements of the end paper taking actuator in the high-speed paper picking process. At the first stage, according to the given ideal position and orientation requirements of the end paper taking actuator, the mathematical model of the five-bar mechanism satisfying the position and angle constraints is established by using the kinematic mapping theory, and two cams are used to constrain the two freedom of the five-bar mechanism to obtain the cam five-bar paper taking mechanism. At the next stage, the relationship between the five-bar mechanism and the cam angle under the given position and angle constraints is solved, and the theoretical profile of the cam is established by using cubic spline curve function. Finally, the whole paper taking mechanism is optimized to obtain the best mechanism parameters. Through the design example of the cam five-bar mechanism of the high-speed packaging machine, it is verified that the designed value taking mechanism can accurately realize the given orientation point, and there is no contour distortion of the cam. This method can not only realize the given position and orientation of the end actuator, but also further optimize cam profile of the paper taking mechanism to improve the running stability and accuracy.