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This paper presents numerical simulation of blanking process using finite element method and comparison of results obtained by analytical solution commonly used in engineering practice. The problem was modeled using axial symmetry. Experimental measurement was used to create multi-linear plastic material model. Results of numerical simulation were used to create history of blanking force vs. tool displacement.

This paper is focused on research in the field of grinding VACO 180 tool steel. Different grinding conditions in terms of several cutting speeds and depths of cut were used for grinding tool steel with CBN grinding wheels. Two CBN grinding wheels with different grain sizes were used for several tests with the same grinding strategy. The influence of the cutting speed and depth of cut on the surface roughness was observed. The different behaviour of both grinding wheels was found during grinding in terms of achieved surface roughness. Higher grain size of the grinding wheel led to higher surface roughness, which increased with cutting speed. However, grinding with deeper cuts showed the opposite effect, and the surface roughness was better at higher cutting speeds. Lower grain size gave a more stable grinding process in terms of achieved surface roughness and lower influence of the cutting speed. However, greater wheel wear occurred during grinding with greater depth of cut. The grinding wheel was dressed before each test to ensure the same grinding ability. The results of this work will be used for a better understanding of the process of grinding tool steel.

Thanks to today’s computer programs, engineers can derive a large amount of information from chemical com-position of a material. This information includes phase transformation temperatures Ac1, Ac3, Ms and Mf. CCT and TTT diagrams for austenite decomposition can be determined as well. When steel is heated, austenite grains nu-cleate and grow in the initial microstructure. On cooling, the grains decompose into pearlite, ferrite, cementite and hardening phases. Transformations of this kind are thoroughly described in literature: the ways the individual phases form and the speed of their formation and temperatures involved. However, in-situ visual recordings of such transformations are relatively rare. With Linkam TS1400XY high-temperature stage and chamber integrat-ed in an optical microscope, one can observe phase transformations in situ during heating and cooling. This paper explores microstructural evolution in 42SiCr steel in the course of heat treatment in a high-temperature chamber on an optical microscope stage which offers observation of changes in the material right under the microscope objective.

The current study investigates the influence of the dressing process of the vitrified bonded microcrystal alumina grinding wheel on the roughness of the machined surfaces in cylindrical grinding of Ti6Al4V alloy using different types of stationary diamond dressing tools. For the research, four types of dressers were selected, which differ from each other by number, size and location of diamond cutting elements. Each dresser has been tested at four different dressing feed values with the same dressing depth. Two sets of experiments were conducted to determine the tendency of grinded parts roughness parameters change depending on the dressing feed for each type of diamond dressing tool at two values of grinding feed. A comparative analysis was carried out to show the dressing feed influence and the effect of the diamond dresser type select on the roughness parameters of the grinded surfaces.

With the rapid development of modern manufacturing technology, people have higher and higher requirements for the quality of mechanical products, and the precision of machine tools for processing mechanical products has gradually increased. Therefore, the development of static pressure guides is particularly important for precision processing industries. The load on the guide rail has an important effect on the thickness of the oil film, and the stability of the oil film thickness directly determines the accuracy of processing. In order to obtain the best control method for the thickness of the oil film, the dimensions of the hydrostatic guide rails and the three-dimensional model of the guide rails were designed and calculated in this paper, and the fuel supply method of the guide rails was determined. The simulation model of the oil film was established and imported from the AMESim software into the FLUENT software to obtain the pressure, velocity, and temperature distribution maps of the oil film. And the pressure distribution data was processed after summarizing. Combined with the relevant mathematical models, the mathematical model of the oil film thickness was finally obtained. Then the Simulink software was used to analyze and the PID control was introduced for comparative analysis. The DOB anti-interference control theory was introduced, and the anti-interference control algorithm was improved. The anti-interference algorithm adapted to the oil film thickness control complete the programming of the modules of the interference controller. The anti-interference control section was created in the Simulink software, and the system of the DOB module was finally completed after packaging. In order to verify the method in t his paper, a static pressure rail test bench was set up, and relevant detection tests were completed. The results of the above studies showed that the control performance was greatly improved after introducing the anti-interference algorithm adapted to the oil film control system.

This experiment assesses the suitability of square-welding high strength steel using the deep penetra-tion welding method, RapidWeld. The aim of this method suitability assessment was to compare the final material properties of three welds, welded accordingly to identical welding procedures. High strength, ultra-fine-grain steel S1100QL (XABO 1100) was used as a parent metal. The suitability con-firmation was based on the achievement of requested mechanical properties of ISO 15614-1 and mo-bile crane manufactures standards. The hardness, strength properties and impact energy measure-ment and evaluatioon of the joint was performed during the experiment. The joint was welded re-peatedly with the use of the same welding parameters for the confirmation of process stability. The achieved mechanical properties fulfill all the requirements. The hardness value deviation is caused by different properties in the heat affected zone. The root cause of the impact energy deviaton was not fully investigated, but the minimal measured values are above requirement. The deviation of the strength characteristics is mininal. The performed experiment has confirmed that the selected weld-ing method is suitable to ensure that the requested material properties of welded high strength, ultra-fine-grained steel are achieved.

The article deals with the use of SPC tools to manage and improve the machining process - drilling furniture elements. The content of the article is to use such SPC tools as basic statistical parameters, box plot, histogram, classic and special control charts, and process capability indicators to assess the drill-ing process and to indicate areas to improve. The article indicates the power of SPC tools in woodwork furniture process control and power of using the Statistica program from TIBCO Software Inc. in this area. SPC tools bring a lot of important and useful information about the analyzed drilling process, its weaknesses, which contributes to the improvement of the process. The conducted study has been shown that the tested drilling process requires improvements, in particular in the area related to the machine and man. The activities that should be implemented to improve the quality of the process were defined, including implementation of the Poka-Yoke system, development of a maintenance inspection schedule, a visual manual for machine setup, employee training with a verification exam, introduction of an employee's suggestion system, modification of the company's motivation system. SPC tools helped to identify the source of process problems, defined a process’s stability and capability to meet a customer requirement, and assist with other insights, that were used to define improvement action.

This paper investigates the replacement of a conventional steel coil spring with a composite disc spring with the aim of minimizing its weight. Simulation in the CAD system Siemens NX 12 was used to determine the composite disc spring’s behavior. The regression functions were stated based on the numerical simulation. Based on the regression functions the solution with the minimum weight was found using software programmed in Matlab. The prototype discs were manufactured from carbon fibre prepreg. Their load-deflection characteristics were tested and compared with the designed values. The experimental results show that using this solution reduces the weight by about 30% in this case.

In this paper, the dependences of the tangential component of the velocity of movement of the medium granules, inside the oscillating reservoir, on its radius and oscillation period are obtained. For the anal-ysis, the circulatory motion of working medium granules under the influence of a rotating impeller and the dynamics of a pseudo-gas from abrasive granules exposed to rotating processed parts and an im-peller, are considered. From the results, the comparison of the energy impact on the working medium of the rotating processed parts and the impeller is carried out and the distribution of the pseudo-gas velocity from the abrasive granules and its pressure on the surface of the processed parts are obtained. Furthermore, the mechanism of pseudo-gas flow around a rotating part from granules of the working medium is presented. Finally, the schemes of the arrangement of the part in a cylindrical reservoir and its flow around the lateral surface of the rotating part are shown.

Planning a process of production, among other machining processes, is an important stage in the production of products. The developed machining process should allow production of parts with the planned dimensional accuracy and specified surface roughness. With reference to the above, the scope of the carried out theoretical work included determining the dependences between parameters of the drilling process, tool wear, as well as the impact of these parameters on the hole quality. The main aim of experimental research was to analyse cutting tools wear in various phases of tool usage. The research consisted in observation of metallographic microsections to analyse changes occurring in the drill bit microstructure. Then the microhardness was measured and in the next step the micro-hardness of the tested drills was statistically compared. Based on the results obtained, the percentage of wear for drill bits depending on microhardness was estimated taking into account the earlier esti-mated Percentable Production Cycle (PPC). This allowed determining the degree of wear and tear of drills by comparing the microstructure and microhardness between them. The aspects of cutting tool management are also discussed.

This work deals with the construction of a steel hangar with a sheet metal shell for storage sports flying equip-ment (SPE) or general aviation aircraft. The design of the building was made to ensure an individual approach to each aircraft. The construction was designed with price and safety in mind. An available option is an electronic security system connected to the central security desk via the Internet, mobile phone or other data transmission.

The milling process is widely used industrially and the quality of the obtained milled products should be controlled because it affects their performance in exercise. This work correlates the quality of the machined surfaces with the adopted locating system, the shape deviations of the workpiece datum and the machine tool. An analytical model was set up and implemented through Matlab® to simulate the quality effects of a milling process. It was applied to two face milling processes characterized by two different locator configurations. It was proved that machine tool volumetric error influences the flatness of the milled surface, while the locator configuration and the datum form deviation affect the orientation of the milled surface, as should be actually.

In this work the influence of material type and sample fill density was evaluated. One PLA material was tested. Test specimens having different fill structure and density were printed from this material. Full honeycomb and gyroid shapes were used for the fill structure. The specimens had four different fill percentages for each structure: 10%, 25%, 50% and 75%. These bodies were compared to samples that were printed with 100% fill. Tensile test was performed on printed test pieces. The Zwick / Roell Z100 was used for testing and the surface hardness of the test specimens was measured by the Shore D method on a DIGI-Test II hardness tester. Fracture surfaces were evaluated on an Olympus DSX 500 optodigital microscope. The results showed that the shape of the fill did not signifi-cantly affect the values obtained by the tensile test. The hardness measurement results showed a different hardness on the bottom surface that was in contact with the printing pad and the top printing surface. Fractographic analysis revealed different types of fracture surfaces related to the printed fill structure.

The presented paper deals with the design of a knee simulator that uses pin-on-ball configuration, ie cartilage and CoCrMo head. The translational motion consists of the cartilage and the rotating head when the load of the articulating pair is derived. The simulator meets the predetermined kinematic conditions according to the ISO 14243-3 standard, including dynamic loading. The simulator is able to record the coefficient of friction during the test, which helps to understand the biotribological processes in the knee. The structural part of the simulator is preceded by a research part, in which the existing simulators and tribometers, which helped to create this design, are analyzed. In the experimental part, specific elements (drives, sensors, etc.) are selected that meet the defined boundary conditions, and the method of friction measurement is determined. The paper concludes with an overall evaluation of the proposed knee joint simulator, which will be able to achieve the conditions according to ISO 14243-3 and at the same time record the course of the coefficient of friction between the cartilage surface and the CoCrMo head.

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

In the performed experiment, changes in the microstructure of steels S265 and X6CrNiTi18-10 due to their chemical-thermal treatment by boriding were studied. The boriding process was performed in a Durborid boriding powder at 900 0C. During this process, surface layers of Fe-B borides were formed in both analyzed sorts of steels. The layers differed in their morphology and composition due to the different degree of alloying of the matrix of analyzed steels by additive elements. The formed Fe-B layers showed high adhesive and cohesive resistance in both materials. Due to changes in the micro-structure of S265 steel, especially due to significant coarsening of the original grain of its matrix, its resistance to tribological abrasion after the boriding process decreased. The opposite effect was ob-served for X6CrNiTi18-10 steels. As a result of boriding, both analyzed materials changed their corro-sion resistance.

In This study vanadium carbide coatings obtained by thermo-reactive deposition/diffusion (TRD) technique on cold work tool steel AISI D3. The TRD treatment were carried out in a molten mixture consisting of NaCl, CaCl2, ferrovanadium and aluminum, by heating this mixture at 1000 °C for 4h using a resistance-heating furnace under air atmosphere. The coating process was investigated using light microscopy LM, scanning electron microscopy/energy dispersive spectroscopy SEM/EDS, and X-ray diffraction XRD characterization techniques. The results indicated that the vanadizing process produced a homogeneous coating layer about 13 µm depth and its microhardness is 2300 HV. Carbide compounds that are formed are vanadium carbides phases (V8C7, VC, V4C3, V6C5, V2C), while EDS-Line scan results show chromium carbides phases formed in sublayer. The corrosion resistance of the vanadium carbide coatings was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in a solution of 3.5 % NaCl. Vanadium carbide coatings improved the corrosion resistance of the substrates, vanadium carbide coatings showed the longest service life compared with the uncoated tool steel AISI D3.

In 1906 Taylor mathematically defined the dependance of tool durability on cutting speed in the form: T=CT/vm for the first time. It is an equation of a hyperbola, which represents itself as a straight line in double logarithmic net according to Taylor. The dependance is valid for the tools made of high-speed steel. It has still been used in spite of the fact that new cutting materials, which cannot be used according to it, or can be used only partially in a narrow range of higher cutting speeds. The course of function T=f(vc) for the tools made of sintered carbid and ceramics will be identified in the paper. It requires extensive durability tests in a wide range of cutting speed. Interesting conclusions can be derived from its course.

In the article, the study of polymer properties is dealt with as a result of production technology on pat-terns, which were made by injecting, machining of the extruded profile and 3D printing. All samples were made from iglidur® J260 material, and they were subsequently tested in order to find out properties of roughness, breaking strength, hardness according to Shore, friction coefficient and swelling. Further-more, the samples were exposed to light microscopy, where material structure was studied, especially from the view of structure defects, distribution and shape of solid lubricants. Based on the performed experiment, it can be stated that production technology affects some properties of the sliding bushing. Above all, properties of the sliding bushing were affected by 3D printing technol-ogy. The measured samples had the worst results with regard to roughness and swelling values. Con-versely, the values acquired by measuring hardness were surprising as the 3D priting samples reached better results than the samples made by machining. The samples created by injection had the best re-sults compared to others in all tests. The measured values corresponded to the values listed by the man-ufacturer. Machined sample of the extruded profile is mainly affected by the type of machining, but with consideration to the structure, it can be claimed that the extruded material has the same structure as an injected piece and its properties, with the exception of surface roughness, are on the same level.

Metal machining is a complex technological process based on material removel from semi-product by the influence of a cutting tool which is abrasion-resistant at high mechanic and heat strain. The essence of material removal is based on considerable material plastic deformation under the tool cutting wedge, the result of which is a deformed chip and transformed workpiece surface, which must comply with the geometrical and mechanical workpiece characteristics. These are determined by selected cutting conditions, geometrical and mechanical characteristics of the cutting tool. The selection of cutting conditions is engineering art and requires deep knowledge of machining process, mainly the relationship between cutting conditions and ther results of machining. These relationships are being tried to identified in the paper.

The topic of the article is the increase of cutting conditions in the machining of heat-resistant steel using exchangeable inserts. The main part is the design of a new technology for machining one of the heat-resistant materials using replaceable inserts, including a discussion of any defects and economic evaluation. The aim is to reduce production costs and contribute to the elimination of production times. These modifications of technologies have a positive effect on the overall economy of produc-tion and the use of new methods in practice. Heat-resistant steels have found application in many branches of production, especially in the aerospace industry for jet engine components. Their specific properties need a more detailed examination of the optimal conditions for their processing.

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.

Measurement results on the Damping Loss Factor (DLF) and Coupling Loss Factor (CLF) between two steel plates is presented for 19 different junction types. The junctions involve joining technologies as line welding, point welding, bolting, riveting, gluing or their combinations, with parameters, such as spac-ing between the junction points or the angle between the plates varying. From the measurement results the DLF and CLF values were calculated by the Power Injection Method for the purposes of being ap-plied in Statistical Energy Analysis simulations. Four excitations were applied at each subsystem by impact hammer, while the response was recorded at sixteen response points at each subsystem. The measured CLF values were compared to each other from various aspects. Data were compared to the results obtained from SEA simulations by using the built-in analytical formulas. In general, good com-parison was observed, although the results appeared to be somewhat dependent on the frequency band. Finally, it was examined whether replacing the DLF values with data obtained for an uncoupled flat plate as well the CLF values with data from analytical formulas leads to acceptable accuracy of the re-sults.

The turning process is one of the most common machining operations in various manufacturing industries. It is conducted by eroding the rotating workpiece using a tool that moves in a linear motion. This study examined the genetic algorithm (GA) as the optimization method for the dry turning process of AISI 316L. GA is a meta-heuristic method that imitates the principle of natural selection, in which the most suitable individuals are selected for reproduction to produce the next generation of offspring. The optimization process was started by executing the selected experimental design based on the process parameters and their levels. The tool nose radius, cutting speed, feed rate, and depth of cut were selected as the process parameters in this study. The outcome of this step was a fitness function that explained the relationship between the process parameters and the material removal rate (MRR) or the surface roughness (SR). GA used the fitness function to produce the optimal process parameters with the highest MRR and the lowest SR in a separate optimization process. The optimization methodology developed in this study can be utilized to predict the optimum value of the MRR and SR for the dry turning process and with less than a 7% deviation from the actual value.

The quality of machine parts is determined not only by the quality of the materials themselves, but also by their heat treatment, which also includes frequently used chemical-thermal processes, such as case-hardening, leading to an increase in the mechanical properties of the surface layers of the material. Heat treatment involves thermal diffusion processes, which are quite complex and therefore there is always a certain probability that the desired material state will not be created. It is therefore desirable to have control methods, preferably of a non-destructive nature, which can detect imperfections and thus prevent future damage that could occur in this way. The paper deals with the use of commonly used non-destructive material testing techniques such as eddy currents, ultrasonic control and acoustic emission method to verify the correctness of thermal and case-hardening processing of steels.

Nowadays, Carbon Fibre Reinforced Polymer (CFRP) materials are extensively used as substitutes for metal parts in aircraft and automotive components since they are lighter in weight. However, mi-cro drilling CFRP materials during the assembly process poses various challenges such as low hole accuracy and delamination. Hence, an experiment has been executed to investigate the influence of micro drilling parameters towards hole accuracy. The spindle speed and feed rate are the machining parameters that have been considered in this experiment. Three different optimum parameters have been obtained from previous experiments, involving the spindle speed combinations of 8,000, 10,762 and 11,017 min-1 with a feed rate of 0.01 mm/rev. A drill bit with a diameter of 0.9 mm is used to drill approximately 300 holes. It has been revealed that the combination of the spindle speed of 11,017 min-1 and feed rate of 0.01 mm/rev produce high hole accuracy at the 2nd hole compared to the 300th hole due to the presence of uncut fibres at the 300th hole which have reduced the hole area. Hence, out-come of this research could provide the benefit to the industries in term of manufacturing time and materials expenditure.

A new Coupler Critical Dimensions (CCD) approach to define mobility criteria (crank, rocker conditions, or existence) for linkage mechanisms has been presented in this paper. The idea is to analyze the extreme lengths of a mechanism coupler link when the mechanism is on the extreme of its existence or changing its mobility condition. The method leads a set of expressions of the constant mechanism parameters that can be used to define the exact dimensional limits of the coupler link in the mechanism. These expressions present sufficient and necessary dimensional conditions for the mechanism existence and become a turning point to change its mobility from crank to a rocker and vice versa. At the boundaries of the coupler dimensions, the mechanism reaches its the change-point configuration where the mechanism may switch either from one work function to another or from existence to non-existence. The method has been successfully applied to the planar 4R, spatial RSSR, and planar multiloop linkage mechanisms. The obtained results prove the effectiveness and accuracy of the method in defining the limits of the mechanism rotatability conditions or existence in general.

Taking a brake drum as the research object, the dynamic characteristics analysis and optimization designare carried out by using the finite element method.In order to increase the stiffness without increasing weight of brake drum, the main design parameters were tested by Box-Behnken experiment design. The three-dimensional model of brake drum was established by using SolidWorks software, then the finite element model of brake drumwasobtainedby imported into ANSYS software and its modal analysis was carried out. On the basis of modal analysis, the three important dimensions of brake drum were defined as input parameters, the drum weight, the first, second and third natural frequencies are defined as output parameters. The response surface model between the input and output parameters was established by using DOE (Design of Experiment). Finally, the input parameters were optimized by multiobjective genetic algorithmand the fivePareto solutionswas obtained. The fifth solution was chosen as the optimal solutionbased on the production technique.The weight of brake drum was not changed obviously after optimization, but the first, second and thirdnatural frequencies were increased by13.07 %, 8.92 % and12.73 %respectively, which provided a new idea for the design and optimization for brake drum.

The AGVs or mobile robots are well used in today’s manufacturing supply technologies and also can be used in engineering’s education. The motion controlling and simulation of such vehicles are a cru-cial question. This paper introduces the steps of motion planning for a driverless carrier vehicle from the positions initially available to the speed of the wheels. The vehicle is located in the High-Tech Logistics Systems Laboratory of the Logistics Institute of the University of Miskolc. For motion con-trolling and simulation between two points the further modules are necessary: 1. path planner, 2. tra-jectory planner, 3. velocity-voltage converter using velocities gained from trajectory planner, 4. mo-tion controlling and simulation of a motor dynamical model using voltages from the converter, 5. simulation of the path and 6. data processing. In this paper the first two modules are detailed, i.e. the path planning and then the trajectory planning. Path planning is based on a new approach, using Bezier-curves and Hermite curves. The trajectory planning tends to the mininum energy, which can be carried out by the examining the current consumption created in the other modules. The smaller consumption originated from the two curves determines the final path and trajectory.

Surface roughness is an important index to evaluate the quality of a machined surface. In order to accurately predict the surface roughness for slow tool servo (STS) turning, taking toric surface as an example, response surface methodology (RSM) was used to perform the process test. The second-order response surface prediction model was established and the variance analysis and reliability test were carried out. The results showed that the average prediction error was 7.6%. In order to obtain the best process parameters, standard particle swarm optimization (PSO) was used. The results showed that the global optimization ability of standard PSO was poor. In order to solve the problem, compression factor was introduced and particle swarm optimization with compression factor (WCF-PSO) was constructed, which enhanced the convergence of PSO effectively. WCF-PSO was used to optimize the process parameters and the results obtained were Rt=0.87mm, af =0.01mm/r, ap=0.05mm, Δθ=8.70°, with a corresponding surface roughness of Ra=0.0486μm. The results of the verification test showed that the actual value was Ra=0.0520μm, and the error was only 7.0%, indi-cating that WCF-PSO had a better optimization effect.