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The propagation and velocity of the deformation wave in the thin isotropic plate is investigated. The deformation is induced by the stroke of impact body onto the facial surface of the plate. The plate is supported perpendicularly. The excitation of the plate oscillation is initialized by a unit force (Heavi-side’s jump). The impact body has a rounded facet by radius c = 2.5 mm. Hook's material model and Kirchhoff’s and Flüegge’s geometric model have been investigated. The analytical solutions for both models are presented. The MATLAB script has been assembled to solve material and geometrical mod-els. The results were compared for two selected points on the surface of the plate. Plate deformation was recorded at two points T1 (at a distance of 20 mm from the impact location on the x axis) and T2 (at a distance of 20 mm from the impact location on the y axis).

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

This article deals with the benefits of PVD coatings ((Al,Ti)N; (Al,Ti,Cr)N and nanocomposite coating nACo®) applied to HSS three edges end milling cutters (producer ZPS - Frezovaci nastroje, Zlin, CZ). The coatings were synthesized by a cathodic-arc deposition process (producer Liss, Roznov pod Radhostem, CZ). Machining was carried out on the vertical milling machine FB 32V with using process liquid. Set up cutting conditions were constant throughout the machining. The aim of this experiment was to compare coated and uncoated HSS end milling cutters and find out the benefits of three kinds of PVD coatings. The monitored parameters were force loading and flank wear. Piezoeletrical dynamometer Kistler 9257B was used for measuring force loading and workshop optical microscope was used for measuring flank wear (criterion VB). The construction steel C45E (1.1191; CSN 41 2050) was used as workpiece material. Best results were achieved by tool with PVD coating (Al,TiCr)N.

An emulation study of the drilling by the spade drill on the spinneret micro-hole is conducted by using FEM analysis software Deform-3D. According to application of finite element software Deform-3D, some characteristic parameter of the work piece and the cutting tool material are set. The distributed situation of cutting force, cutting temperature and tool wear in different cutting parameters are simulated analysis. By discussing the location of the spade drill drilling wear, further optimization of parameters cutting and tool for the spinneret micro-hole drilling provide the better basis.

Nowadays, to reduce vibrations of machines, damping devices utilize the eddy current damping ef-fect being increasingly investigated for its advantages of no mechanical contact, no viscous liquid required, high reliability, and good damping capacity. This article studied the main principle of the eddy current damping effect for a moving permanent magnet in a stationary and electrically conduc-tive nonmagnetic cylindrical tube. The magnetic damping coefficient is investigated experimentally, analytically, and by numerical simulations in a steady-state. The numerical simulation is performed in the ANSYS Maxwell programme. The obtained results indicate that the damping force affecting the moving magnet has a viscous form. The experimentally measured and computed results are in good agreement. The effect of varying tube diameter and the tube wall thickness on the magnetic damping coefficient is shown. The contribution of this article consists in the development and a comparison of the obtained results of three approaches for determining the magnetic damping coefficient for a mov-ing magnet in a cylindrical tube.

Nickel-based superalloy GH4169 has high strength and stability at high temperature and is widely used in aerospace and military fields.However, due to the problems of hard spots and poor thermal conductivity in actual processing,it is difficult for workers to select reasonable processing parameters during processing,which increases the difficulty of processing.In order to optimize the milling parameters,reduce the milling cost and operational difficulties in actual machining,we used ABAQUS finite element analysis software to simulate the 3D milling of GH4169 nickel base superalloy.The variation of milling force during milling was studied.The influences of milling speed,feed per tooth and radial depth on milling force were analyzed and the results of the simulation were compared with those obtained by orthogonal experiment.The variation of milling force was verified.Finally,we obtained the reasonable milling parameters.

Experience with the use of NC machine tools shows that cutting conditions cannot be optimized without a more detailed knowledge of the machining process. The essence of the adaptive machining system lies in the response to he machining conditions (change in allowance, cutting width, material hardness). In doing so, it allowance a constant selected parameter, e. g. cutting force.

At logging and at the subsequent wood and wood semi-products treatment and also at fruit trees treatment the fine grained loose waste is arising, e.g. wood dust, saw dust, shavings, chips, bark etc. One of possibilities of its meaningful utilization is the briquetting technology, which product are briquettes determined for energetic utilization (combustion). In the paper the experimental results are published. The briquettes quality evaluation was their aim. For the tests pine bark chips, fir chips, spruce shavings, spruce sawdust, apple chips and cherry chips were used The basic physical-mechanical properties were the evaluation criteria. Following properties were determined: ash amount, gross calorific value, total moisture content, density, rupture force, length, diameter, weight and mechanical durability.

The paper presents the possibilities of using the wavelet transform to filter the cutting force signal. Tests were carried out by dry turning on the Ti6Al4V alloy with variable cutting parameters. Four blades with different nose geometry and coatings were used. From the recorded waveforms, the mean values of the force component Fc and the load stability coefficient were calculated. The measured force waveforms were filtered with Daubechies 4 (db4) and Daubechies 6 (db6) wavelets. From the ratio of the load stabil-ity after filtration to the load stability before filtration, the noise and disturbance values generated during the turning of the tested alloy and the force measurement were estimated. The conducted research shows how the machining conditions affect the values of force, stability, and thus also the variability of the cutting edge load when turning a titanium alloy. They also show the effectiveness of the Discrete Wave-let Transform (DWT) in separating the noise from the force signal.

One of the ways to improve or change the surface properties of materials is to apply thin layers. TiO2-based layers are used to protect surfaces against wear or atmospheric and thermal effects (anti-corrosion, anti-abrasive and anti-static layers). They are also used in optical coatings, on windows or glasses (anti-reflective, self-cleaning and conductive transparent layers), in healthcare and in households to ensure the cleanliness of surfaces. The work deals with the effect of TiO2 layers on the surface properties of selected substrates. The layers were prepared by the sol-gel method using the dip-coating technique on glass and stainless steel. The morphology and topography of the surfaces of the uncoated and coated substrates were evaluated by atomic force microscopy. Scanning electron microscopy was used to determine the layer thickness. The effect of TiO2 layers on the surface properties of materials was also evaluated using wetting angles, surface energy and its polar and dispersion components. Based on the results, especially the higher surface energy value, we can conclude that the TiO2 layer influenced the surface properties of the studied solid materials.

The use of spinning technology for the outer flanging of cylindrical parts can save moulds, reduce labour intensity, and improve production efficiency. Therefore, two finite element models for the outer flanging spinning with the flange radius of 4 mm and 5 mm are established in this article. The deformation process, stress-strain field, and wall thickness distribution of the flange during the spinning period are analyzed. It can be found from the simulation results that, the blank of both working conditions cannot fit the contour of the roller until the until 2.5 s before the end of the spinning process, and it is more difficult to achieve fitting with a smaller profiling radius of 4 mm. The x-direction force caused by the 4mm profiling radius is less than that by the 5mm one before the end of forming due to the smaller contact area with the roller. According to deformation in a relatively cramped area, the wall thickness distribution under the condition with a larger curvature is generally slightly greater than that with a smaller one.

Due to the complexity of the current industrial pipeline layout, in order to improve the efficiency of pipeline inspection and maintenance, a multi-functional obstacle-surmounting pipe-crawling robot was designed to address the issues of varying pipe diameters and positions. The movement pattern of the crawling robot was studied, the variation of the clamping force of the clamping mechanism during the climbing process was analyzed, and the mapping relationship between various parameters was obtained as the basis for later kinematic simulation. The design of inverted V, positive V and other drive combinations and the planning of multi-functional obstacle-surmounting actions were conducted to verify the rationality of the structural design and the stability of the motion process of the multi-functional obstacle-surmounting pipe-crawling robot. Results showed that the multi-functional obstacle-surmounting pipe-crawling robot can achieve the expected crawling speed of 0.3m/s when moving on a horizontal pipeline, and the motion process is stable. When moving on a vertical pipeline, from the speed and displacement curve of the robot on the x, y, and z axes, it can be seen that the speed and displacement of the pipe-crawling robot are steadily increasing without any left or right swing, indicating that the clamping mechanism works well and the structural design is reasonable.

Grinding is one of the most important processes in machining precision rotating parts. GF & GT (grinding force and grinding temperature) of single particle in grinding wheel have great influence on surface roughness. This study established the GF & GT models of single particles. Abaqus was used to analyze the coupling between GF & GT of single particle. Combined with grinding parameters (grinding depth and grinding speed), the influence of GF & GT on the range of surface roughness of single particle abrasive was comprehensively studied. The machining and experimental analysis of precision aerospace bearings were carried out through theoretical analysis. The results show that with the increase of grinding depth, the GF & GT in X and Z directions increase gradually. However, the grinding temperature does not increase linearly with the increase of grinding depth. Compared with the grinding speed, the influence of grinding depth on the grinding force in Y and Z directions is much greater than that in X, which is 7.38 times and 5.81 times of the grinding speed, respectively. Grinding depth has the greatest influence on surface roughness, which is 3.6 times the grinding speed. When the test speed is constant at
60000 rev/min, the bearing temperature is between 30 °C and 65 °C and most of them are within 44 °C. The test data meet the requirements, and all indexes are controllable. The above conclusions provide a theoretical basis and selection of process optimization parameters for grinding precision rotating parts.

A constant tension cable reel based on planetary gear transmission is introduced. The parameters of the mechanism are determined to analyze the speed and torque of the transfer mechanism. The relationship between the thread pitch and cable type show that different cable models require different parameters for the constant tension cable reel. The mechanism is designed to automatically adjust the force required for cable pulling and maintain a constant maximum tension. Then the relationship between the moment and speed of each output shaft is analyzed, and the operation mode of the cable reel was explained. The experimental results show that the proposed cable reel can pull the cable flexibly while providing the required constant tension, without damaging the cable and extending its service life. The pitch of the screw-thread pair is directly related to the required tension of the cable and the cable diameter. If the power supply cable model is different, the parameters of constant tension cable reel are also different.

Article deals with comparison of cutting forces and surface roughness between materials produced by powder metallurgy M390 and M398 Microclean® from producer, company Böhler. Main interest is the analysis & comparison of the cutting forces and surface roughness after the processing by cutting in-serts with DNMG and WNMG geometry, radius 0.4 and 0.8 mm, after hard turning at the same pro-cess parameters for both materials and all types of cutting inserts. The comparative studies were car-ried out for cutting forces and surface roughness with the aiming to observe the difference between “old generation” M390 and “new generation” M398 PM Steel for future processing in production. The corelation between the cutting forces and surface roughness was investigated with resulting the M398 is necessary to process by higher cutting forces which are linked with higher surface roughness than at M390. It is in relation with higher contain of additive elements and carbides formed by them, even that the material is in delivered condition – soft annealed [1], [2]. These results helped to fulfil the knowledge about both materials in the row of experiments which are provided to increase material properties against abrasion and wear.

The Male and Cockroft ring compression test is one of the methods used to determine the coefficient of friction in forming. This method can be used to determine the coefficient of friction without the need to measure the force. This paper describes the results of the Male and Cockroft ring compres-sion test for the Hardox 450 material at different strain rates. The experiment was performed on ZD40 hydraulic press and CFA-80 pneumatic die hammer at the Faculty of Mechanical Engineering of Brno University of Technology. The test results were recorded in a calibration diagram. The results show that the strain rate has a significant effect on the coefficient of friction, specifically such that as the strain rate increases, the coefficient of friction decreases.

In response to the need for trajectory correction during the excavation of curved tunnels by tunnel boring machines(TBM), as well as the impact of interference forces generated by the propulsion sys-tem on the design and service life of key components, as well as the low propulsion efficiency of TBM, a dynamic model of the propulsion mechanism during the excavation process is established, and the variation law of the angle between the key components of the thrust hydraulic cylinder and the gripper shoe hydraulic cylinder under the propulsion force of the hydraulic cylinder (1500KN) and three steer-ing angles of 0.5 °, 1 °, and 2 °, as well as the relationship between the gripper shoe hydraulic cyl-inder tightening force and horizontal propulsion force, has been studied. Research has shown that under the rated hydraulic cylinder propulsion force, during the process of increasing the swing angle of the main beam, the left angle and the tightening force on the left gripper shoe are less than the straight-line working condition, while the right side is greater than the straight-line working condition. However, during the forward excavation process after turning left, the X-direction propulsion force provided by the left thrust cylinder is greater than the X-direction propulsion force of the horizontal excavation, and the force on the left support shoe is less than the tightening force under the horizontal working condition, while the opposite is true for the right side. The research results have important theoretical significance for studying the optimal matching relationship between the mechanical model and excavation parameters of TBM during the propulsion process, as well as further improving the excavation efficiency and stability of TBM.

In drilling operations, hole quality is affected by factors such as drill diameter, drilling parameters, drill bit properties, workpiece material. A large portion of the drilling energy is converted into thermal energy, which can be measured as temperature. In this study, surface roughness of holes, drill tip wear and drill tip temperatures were determined using two different workpiece materials and three different drill tips. Furthermore, the costs of holes drilled with different drill bits were determined and interpreted based on drill bit characteristics. The results obtained can be optimized according to the process parameters and it has been shown that a more sustainable and much more economical manufacturing can be achieved by avoiding the use of additional reaming or internal grinding for the desired surface quality and eliminating negative environmental effects.

It is a well-known fact that during cutting there occurs an extremely high degree of chip plastic deformation [1,4,5,11] These deformation structures require attention as they influence technical and economical results of cutting (cutting forces, quality of machined surface, tool wear, cutting temperature) [8,9,15,21]. The paper analyses the options of influencing the deformation field in chip with the aim to improve cutting proces.

The main aim of this scientific article is to assess the contribution of surface layers by determining the experimental investigation and practical measurement of surface roughness Ra and selected components of cutting forces while external turning of AlCu3MgMnPb aluminium alloy. In these experimental procedures, a number of turning tests have been carried out by using a universal lathe machine tool and cutting forces and surface roughness scientific measuring devices. These realized measurements have been successively investigated and experimentally verified with the prepared trial samples. These presented experimental measurements describes the authors investigation of cutting forces while turning by the piezoelectric dynamometer Kistler type 5001 and surface roughness Ra with the Talysurf CLI 100 measuring device. This scientific article, together with measured and calculated results, is the fundamental that will help to optimizing the quality and used other technological and cutting parameters of turning technological process.

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.

Nowadays the pressure to increase the efficiency of the machining processes is constantly growing. The efficiency of the machining process can be pursued from two basic perspectives - enhancing the cost-effectiveness of the process (decreasing production costs) or increasing production in time. Via these approaches alone, manufacturers of parts as well as suppliers of machine tools and cutting tools try to improve their position in a highly competitive market. One of the approaches to increase efficiency is the correct choice and subsequent optimal exploitation of the potential of cutting tools and machine tools as well as a reduction in the energy intensity of the cutting processes for a given component. That is what led to the idea of creating an analytical-material model for determining the force interaction between the cutting tool and workpiece, energy intensity and machining process efficiency. The result will be an application that helps technologists in practice to choose correctly the appropriate types of cutting tools, operations, machine tools and also quickly determine the main parameters of the cutting process so that there is the possibility of comparing their results with other variants. The first step and goal is to create an overview of the cutting processes and the associated cutting process modelling, compare their advantages and disadvantages, and then propose an approach of our own.

In order to test whether the design of the new steel mold trolley meets the requirements of the working conditions,the ANSYS finite element simulation and optimization analysis of the frame system of the new steel mold trolley were conducted.After the analysis, the results show that the new steel mold trolley designed basically meets the requirements of strength and stiffness, but there are some problems of insufficient strength；Through the topology optimization of the gantry frame of the new steel mold trolley frame system, the "door shape" section gantry structure with better force structure was obtained.The influence of the specific structural parameters of the "door shape" cross-section gantry structure on the overall stress of the steel mold trolley frame system was studied.The results show that the optimized steel mold trolley gantry structure has a maximum stress of 174.94MPa, an average stress of 26.22Mpa and a maximum deformation of 2.20mm under the condition of extreme load, which can better meet the actual engineering needs.

In vibration-assisted drilling, the wear state of the drill bit affects the processing quality of the hole. The traditional method of identifying the wear state of the drill bit adopts the method of packet de-composition, ignoring the timing characteristics of the signal. In this paper, the force and acoustic emission signals in vibration-assisted drilling are used. The Gram angle field converts the one-dimensional time series into a two-dimensional image, while retaining the trajectory of the time se-ries in the high-dimensional space. Based on the Graham difference field (GADF) image of force and AE, the Inception improved convolutional neural network (IN-CNN) is used to identify the wear state. The experiment proves that compared with the traditional convolutional neural network, BP neural network and support vector machine, the recognition rate of IN-CNN drill wear state based on GADF is 93.1 %, which is increased by 2.5 %, 10.6 % and 8.1 % respectively. It provides a reliable condition monitoring method for the state identification of the drill bit in semi-closed vibration-assisted machining, and has practical engineering significance for improving the machining accuracy and efficiency of composite equal-holes.

This study aimed to investigate the influence of single-wall carbon nanotube (SWCNT) content on the mechanical properties of polyurethane (PU) nanocomposites. The SWCNT content varied from 0 wt% (reference sample) to 2 wt%. Tensile, hardness and Charpy impact tests as well as dynamic me-chanical analysis (DMA) were performed. Based on the test results it was observed that an increase in the content of single-wall carbon nanotubes resulted in significant improvements in material strength and stiffness. Furthermore, atomic force microscopy (AFM) was used to examine microsurface to-pography of the samples and to obtain spectroscopic curves, based on which local elasticity was eval-uated. Overall, performed measurements indicate that the incorporation of SWCNTs into PU matrix makes resultant nanocomposite stiffer and more resistant to deformation. The results highlight the potential of SWCNTs as effective reinforcement of polyurethane-based nanocomposites.

The aim of this article is to approach the measurement of forces and pressures of collaborative robots. In the article, research will be carried out on measuring the forces and pressures of a collaborative robot before putting it into real application. Force and pressure values will be measured using appropriate measuring devices. The measured results will be compared with the ISO/TS 15066:2016 technical specifi-cation and subsequently evaluated.

The modelling of dynamical systems with mutual interaction through normal and tangential forces between surfaces is one of the most important tasks in the current computational research. The paper deals with the formulation of the equations of motion in dynamics of multibody systems and subsequent usage of various contact force models. Four types of normal force calculations are introduced and their behaviour is demonstrated using a simple example of a sphere moving towards a plane. The parametric study of the contact models with respect to the coefficient of restitution and an exponential parameter is performed. In order to show a more practical usage the simplified dynamic model of a nuclear reactor control assembly is created and its dynamic response is discussed. The model is characterized as a falling rigid body in a narrow channel filled by a fluid.

In this paper, the adhesive behaviour of different polyurethane glues was studied and compared. The study was inspired by real conditions in the production of car windows, and it is divided into several parts, which deal with three types of polyurethane adhesives. The first type is a standard one-component polyurethane adhesive, which cures with air humidity. The second type is a one-component polyurethane adhesive with the addition of a curing accelerator. And the third type is a two-component polyurethane adhesive. Adhesive blocks of defined dimensions and plastic parts glued to the glass were used for this experiment to simulate a real product. The influence of temperature and humidity on the curing process was evaluated. The test included measuring the force required to tear the parts from the glass and assessing the type of failure. Based on the achieved results, the adhesives were evaluated regarding their applicability in the real automotive industry and the key properties necessary to maintain the safety and quality of the glued part were determined

Nickel-based superalloy is a kind of metal material that is widely used to manufacture high-temperature parts in the fields of aviation and aerospace, but it is also a typical difficult-to-machining material. The precision cutting of nickel-based superalloy has always been an important manufacturing problem. Based on the tests of conventional drilling with three kinds of twist drills, the machinability of Inconel 718 was evaluated comprehensively by drilling force, tool wear and machining quality, and the cutting tools suitable for drilling nickel-based superalloy were chosen. Then the experiments of peck-drilling for Inconel 718 were carried out, and the process effect under different peck depth Q was deeply researched. The results showed that the HSS-Co (high speed steel with cobalt) twist drill can meet the needs of low-speed drilling of nickel-based superalloy, while the coated carbide twist drill has better service performance. The drill tip structure of dual clearance angle is beneficial to decrease the cutting friction and improve the machining accuracy. Compared with conventional drilling, the peck-drilling can reduce the cutting force and improve the dimensional accuracy and surface quality. However, it is very important to choose a suitable peck depth Q for fully exploiting the advantages of peck-drilling.

Testing of machinability of the UMCo50 superalloy was carried out within the project following the actual production of the semi-finished product by casting. Turning was chosen as the machining method to minimize the effect of an interrupted cut. Considering the machinability of a hard-to-machine alloy, the cutting material with the fine-grained WC-Co carbide with the TiN/TiAlN gradient PVD coating was selected. The progression of cutting forces, chip formation and tool wear were evaluated. Images of the material structure of the semi-finished product and the resulting chips were taken. From the measured values, graphs of the dependence of the chip thickness ratio on the cutting speed and the Taylor´s dependence of the tool durability on the cutting speed were obtained. The aim of the experiment was selection and verification of suitable cutting conditions for efficient machining of this superalloy, especially the appropriate value of the cutting speed. The recommended value of the cutting speed was 50-70 m.min-1, while the tangential component of the cutting force was in the values usual for corrosion-resistant steels.