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The article presents the results of experimental research on creating the mobile continuous earthmoving machin-ery. Methods for performing field experimental studies and measuring equipment used are described. The article shows the data of experimental research, their analysis, the determination of physical nature of changes in exter-nal load characteristics of the machinery operating equipment. The conducted experimental studies of modern mobile earthmoving machinery enabled to establish its technical capabilities, the characteristics of the power load of the operating equipment when developing the soil. It also enabled to determine the ways and directions for mod-ernizing the operating equipment of machinery. One of the ways is to optimize technological combination of soil cutting, displacement of the developed soil to the unloading area and unloading of the actuator. The research per-formed and the results obtained have enabled to experimentally confirm the effectiveness of the technical pro-posals to create the design of the chain and bar actuators with impulse soil unloading intensifiers for trenchers implemented in the industry.

The article presents partial results of research to increase the service life of snow ploughshares, which are used for winter maintenance of forest transport roads. The main working tool of vehicles - snow plough is the arrow ploughshare. It is made as a weldment. The contact tool, when in contact with the road, is the rake blade, which is subject to abrasive wear. The experiment consisted of analysing the current state of materials, designing and exploring such options that would ensure a longer ser-vice life of the blades. Welding material was designed to be applied to the base material of the blade. Furthermore, the HARDOX 450 was designed for the production of the whole ploughshare. The last design was welding HARDOX 450 with an electrode OK 48.00 with the base material steel 11 484. This proposal is presented in more detail in the article. The hardness of HBW, HV and HRC was measured on the samples and microscopic analysis was performed using light and electron microsco-py. The aim was to determine the quality of the connection of materials, mixing in the connection zone and comparison with the condition on the original blade. It is assumed that a suitable choice of welding electrode or a suitable choice of abrasion-resistant steel can achieve an effective increase in the life of the snow plougshare, whether from a technical or economic point of view.

The paper present the structural design of freight wagon chassis frame with adaptable loading platform with regard to the safe operation and assessment of the properties by the calculation methods of simulation analysis. 3D model of wagon was created in a computer program PTC/Creo. Wagon chassis frame was subjected to the static and dynamic analysis in programs ANSYS and ADAMS/Rail. On the basis of computer aided simulation analysis was optimized the frame of the wagon. This wagon chassis frame will be able to offer even more capacity and utilize less resources and energy than current wagons for intermodal transport.

In the recent years, the demand for weight reduction in modern vehicle construction has led to an increase in the application of hydroforming processes for production of automotive and aerospace lightweight components. The tube hydroforming measurement site (TH stand), designed and built at Warsaw University of Technology allows both die, and free tube hydroforming processes to be performed, thereby making it possible to obtain information about the material, as well as optimal process parameters [1][2]. The present freshly patented method for metal tube hydroforming is dedicated to short product series or even single products and prototypes [3]. The method is applicable to forming difficult-to-machine materials. The well-known techniques use dies made of plastic or wood, especially to form short product series. The use of moulding sand and properly prepared geometry of casting mould makes possible shaping materials at high temperatures, which could not be done in previous short series solutions, where a plastic or wooden die were used. [1] Sadłowska H., Jasiński C. Morawiński Ł., Strain measurements on the tube hydroforming testing machine, Archives of Metals and Metallurgy Vol. 65 , Issue 1, 2020, pp. 257-263 [2] Sadłowska H., Odkształcanie się rur podczas swobodnego rozpęczania hydromechanicznego na stanowisku TH, w: Prace Naukowe Politechniki Warszawskiej. Mechanika, Vol. 267, 2015, ss. 25-30 (in Polish) [3] Patent No. PL424401, Kochański A., Sadłowska H., Bulletin of the Patent Office of Inventions and Utility Models vol. 17_2019, pp. 11

This work deals with the effect of the cutting conditions and the spindle tilt on the surface roughness when grinding complex shaped surfaces of Maraging steel MS1 on an ANCA MX7 5-axis tool grinding machine. It is necessary to grind complex shaped surfaces where high surface quality is important and requested. For this experiment was selected a component with a complex shaped surface which was printed on the 3D printer machine from maraging steel MS1. Since grinding of complex surfaces is being investigated, it is necessary to use CAM software for creat-ing an NC program. The aim of this work is to study the effects of the cutting conditions on the grinding of a com-plex shaped surface in relation to the resulting surface roughness. To do this, it was necessary to design an experi-ment with the appropriate grinding technology, create a clamp, and create NC data in NX CAM software for grinding the complex shape surfaces on the part.

The article presents the results of theoretical research on creating the mobile continuous earthmoving machinery. The aim of the article is to develop and evaluate the effectiveness of technical decisions when creating and mod-ernizing trencher chain and bar actuators. The peculiarity of the performed research is a complex way to solve the problems of ensuring the efficient operation of the earthmoving machinery. It involves a combination of two subsystems: "soil - operating equipment" and "basic chassis ? bearing capacity of soil surface". The mechanisms of changing the power parameters of the machinery load are established. The input parameters for a system de-scribing the operation of a special earthmoving machinery are soil physical and mechanical characteristics and the dimensions of the earth excavation, the installed power of the basic chassis engine, the type and characteristics of transmissions of the machinery operating equipment and chassis propulsion, geometric parameters of single cutters, the speed of cutting the soil and moving the machinery. The mathematical model of the system as a whole makes it possible to determine the rational design, kinematic and energy characteristics of the machinery and its operating equipment. It minimizes the energy intensity of soil development.

Laboratory fatigue testing is an important part of the fatigue design of machine components that are supposed to work under cyclic loading. These tests are used to confirm whether the tested component matches the required fatigue life and they also serve as a verification of the numerical calculations. This paper describes a fatigue life testing of a welded steel construction. The testing was carried out in the Regional Technological Institute (RTI) using an electro-hydraulic loading system, which allows realization of the tests simulating a real service. An integral part of the fatigue tests is a pre-scheduled inspection of the crack initiation and propagation. The tested construction was checked using non-destructive magnetic particle testing before the fatigue test and also during and after the performed test. Some cracks were observed, especially in the weld area. The biggest crack had the length of approximately 40 cm. This crack was cut out and underwent detailed metallographic and fractographic analysis to estimate the effect of material purity and quality of the weld on the fracture.

The paper deals with dynamic in-plane simulation analysis of a motorcycle suspension. The motorcy-cle᾿s mechanical model is considered as a visco-elastically suspended rigid body. Two types of the kinematic excitation are considered ‒ a deterministic „hat“ shaped bump and stochastically uneven road characterized by its power spectral density. The simulation results for both the deterministic bump and stochastically uneven road show that significant reduction of the root mean square value of the motorcycle body centroid acceleration (comfort criterion) can be achieved by placing the lower end point of the rare spring-damper module closer to the beginning of the swinging arm and also by increasing deviation (tilt) of the spring-damper module from the vertical. The maximum improvement in the root mean square value of the motorcycle body centroid acceleration is 51.7 % for the deterministic „hat“ shaped bump and 37.4 % for the stochastically uneven road. The method presented in the paper can be employed in design of both touring motorcycles, which are characterized by higher requirements of comfort, and off-road motorcycles where protection from impacts generated by bumps is important.

The impact of plasma nitriding process on corrosion resistance of ferritic stainless steel (FSS) was evaluated in this study. The FSS X12Cr13 (AISI 410) was subjected to low-temperature plasma nitriding (LTPN) treatment at a temperature of 400°C in 3H2:1N2 (l/h) and in 1H2:3N2 (l/h) reverse working atmosphere (LTPN-R) and to high-temperature plasma nitriding (HTPN) treatment at 550 °C for 15 h. The microstructure and microhardness of the untreated and nitrided stainless steel were evaluated. The corrosion properties of the untreated and plasma nitrided steel samples were evaluated using the anodic potentiodynamic polarization tests in neutral 2.5% NaCl deaerated solution. The phase analysis showed that LTPN and LTPN-R treatment on the AISI 410 steel led to the formation of N layer (nitrogen expanded ferrite) accompanied by Fe3C and Fe4N iron nitrides and CrN. The HTPN technique led additionally to the formation of an increased volume of Cr4N4 chromium nitrides and Cr15Fe7C6 chromium iron carbide. The plasma nitriding process significantly increased the microhardness of the ferritic stainless steel. The pitting was evaluated, and the pitting coefficient was calculated. The electrochemical corrosion tests showed the best corrosion resistance of the untreated X12Cr13 stainless steel, only slightly increased corrosion rates of LTPN and LTPN-R techniques, and extreme corrosion rates after application of the HTPN technique, causing Cr depletion and thereby suppressing the ability to passivation.

Direct Metal Laser Sintering (DMLS) is a method which builds metal parts in a layer by layer procedure. The melting of metal powder by a laser beam is a complex physical metallurgical process and successful processing of the whole manufacturing procedure requires complex management. Therefore, a successful result is not guaran-teed. The print job is designed based on the designer?s personal experience, and the possibility to verify the cor-rectness of a job proposal would save time and money. Nowadays, there are many kinds of software which allow timely detection of errors in the print job design. This paper deals with demonstrations of print task simulations. The results from actual simulations are useful as support for the print job designer, but they do not completely substitute for real production tests of parts.

This paper focuses on the structural design of screw tools in briquetting presses used for the production of solid, high quality, bio fuels. The primary objective is to analyse the screw tool geometry and determine a procedure for its design, specifically the theory involved with the pressing tool and force relations which are necessary for the verification of the proposed tool geometry and its strength analysis. In designing the main drive of the press, procedures for determining frictional performance of the screw press are used. Familiarity with the above mentioned procedures forms the basis for research into new tools in screw briquetting presses that will improve the service life and competitiveness of the technology.

The vertical stability coil is a new set of saddle shaped non-superconducting coil designed for the purpose of improving the control capability of plasma vertical movement. To avoid the electromagnetic shielding and en-hance the response performance, the vertical stability coil is installed in the inner wall of vacuum vessel. The subsequent disadvantage accompanying the benefit is that the coil is under severe neutron radiation. Besides the neutron radiation the coil will also encounter the ohmic heat once it is energized. The temperature rising of vertical stability coil is not allowed to beyond the specific threshold to guarantee the reliability of the coil com-ponents. Thus, the ohmic heat and nuclear heat calculation methods are presented and the detail temperature field is analysed by using ANSYS to check whether or not the coil can bear the thermal load. In addition, the thermal load will result in the thermal stress. To verify whether the thermal stress will lead to the structural damage, the thermal-structural coupling analysis is launched and the stress is evaluated based on ASME ana-lytical design. The analysis results will provide guidance for the local structural optimization of vertical stabil-ity coil.

Machining technology is a widely used chip technology designed for the production of segmented parts. It is widely used in almost all branches of industry, including the automotive industry. Here, the investigated alloy 2024 is widely used. A critical factor in the current design of many of these advanced systems is accurate knowledge of degradation behavior in the work environment in the context of surface condition after surface machining. If this environment causes surface discontinuities, they will significantly affect the life of the part. Corrosion behavior is considered to be an extremely critical factor due to its effect on the service life of the structure. Due to the many complexities that have developed in relation to surface condition and corrosion, little useful technical information is available. The aim of the article was to determine the effect of the surface condition on the corrosion behavior of alloy 2024. The chemical composition of the alloy was evaluated by spectral analysis. Furthermore, the samples were evaluated by confocal microscopy and the elemental distribution in the microstructure of the 2024 alloy was analyzed with emphasis on the Al2Cu phase distribution. The individual structural phases were performed using a scanning electron microscope with an EDS analyzer. This article is part of a larger experiment that will focus on the subsequent modification of this alloy, in order to change the microstructure and skin resistance of castings.

In conventional steels, bainitic microstructure which forms under isothermal conditions consists of bainitic ferrite and carbide precipitates whose distribution and size substantially depend on the pa-rameters of isothermal treatment. In CFB steels (Carbide Free Bainite) however, the main micro-structural constituents are bainitic ferrite, retained austenite and, sometimes, the M-A constituent. CFB microstructure may possess better ductility and the same or even higher strength than micro-structures of bainitic ferrite and carbide precipitates. This advantage results from the principle of formation of the CFB microstructure and is related to the absence of brittle carbides and their substi-tution with retained austenite. This paper explores the effect of austempering on mechanical proper-ties of unconventional CFB steels 42SiCr and 42SiMn.

The article presents a comprehensive example that demonstrates the control of a plastic injection process in practice. It includes measurement and analysis of the production process, its control using a control diagram to bring the production process to a state under statistical control by applying tests of non-random clusters and subsequent evaluation of process capability. The last part of the article gives an example of the maintenance of economical statistical optimization for four scenarios.

This article summarizes the results from the fire resistance test of geopolymer suspensions in the form of coatings on non-metallic substrates. Their heat resistance was evaluated based on the burn-through time compared to the uncoated substrate. Non-metallic substrate materials, extruded polystyrene (XPS) and chipboard (DTD) were chosen as the underlying substrates for GP suspension research. Parameters from the fire resistance test as fire test duration of geopolymer coatings and percentage increase in burn time of geopolymer coatings on an XPS and DTD substrates compared to an uncoated substrate were evaluated. One of the discussed point was also the addition of CaCO3 and Al(OH)3 for studding flame retardancy effect.

The presented study focuses on the study of polylactide acid (PLA) material, which is a frequently used material in 3D printing. Surface modification using DCSBD plasma discharge is proposed as a way to improve the adhesion between individual layers of material. Adhesion is a critical factor for achieving high-quality print output, as low adhesion can cause individual deposited layers of material to separate and ripple during printing. Dynamic Mechanical Analysis (DMA) is used to determine the glass transition temperature (Tg) of a material. Tg is important because it determines how difficult the material is to print, the closer the Tg is to room temperature, the easier the material is to print. How-ever, after printing a layer of material and subsequently cooling it to room temperature, the material begins to shrink and wave due to the change in material expansion. This can have a negative effect on the adhesion between the layers of the material, which can lead to separation of the layers. The presented study tries to find a way to improve the adhesion of individual layers of material. Surface modification by plasma discharge appears to be a promising method that could improve the adhesion between individual layers of PLA material.

Additive manufacturing commonly also called 3D printing is a process which creates 3D structures according to digital 3D models by successive deposition of material layer by layer. Electrochemical 3D printing is a relatively new form of additive manufacturing, which creates metallic structures by electrochemical reduction of metallic ions from the electrolyte onto a conductive substrate. Advantages of this technology are ability to produce structures of several materials, without inert atmosphere, thermal stresses and without using laser optics. Theoretical part was focused on introduction to additive manufacturing and overview on its technologies, description of principle of electrochemical deposition, overview on electrochemical additive manufacturing technologies and influence of parameters, which affect it. Experiments were focused on effect of selected parameters of electrochemical 3D printing on print rate, mechanical properties, porosity, and microstructure of built structures of copper.

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.

The presented work deals with the research of the super-alloy Inconel 713LC, on which an Al-based coating was applied using the "Out-of-pack" diffusion coating process, or CrAl. In this contribution, the results of measuring the thickness of thin coatings using a confocal laser microscope and the method of impedance spectroscopy are presented and discussed. This can demonstrate the possibility of being used also for researching the properties of thin layers using a VF probe, which, thanks to the use of ferrite, has a practically constant inductance in the entire frequency range, and the presence of a metal sample in the magnetic circuit of the probe was manifested as a result of eddy currents by a significant decrease in the inductance value at higher frequencies. However, the measurements require precise measurement of impedance with an accuracy of 1mΩ and phase angle with an accuracy of 0.001° with high stability of the measuring frequency. For a better assessment of the parameters of the layers, it is necessary to extend the frequency range of the measurement to the range of MHz units.

The main aim of this case study is to present the changes caused by heat treatment on the structure and properties of 100Cr6 steel by annealing, hardening, and tempering in combination with previous chemical-heat treatment (CHT) by boriding. The boriding causes changes to the microstructure of the steel samples, which include a change in the morphology of the deposited cementite and a change in the volume of the chromium carbide particles. The cementite is transformed from its original granular form to a lamellar form. An increase in the proportion of chromium carbide particles in the sample occurs due to the higher affinity of chromium for carbon. This leads to precipitation of chromium carbides rather than carbides of iron. A multi-phase diffusion layer Fe2B-FeB with a thickness of 31 ± 2.8 µm is formed during boriding, with a typical tooth-like texture. Although the diffusion layer does not have the same toughness and resistance as the single-phase Fe2B diffusion layer, samples after boriding increase their resistance to tribological abrasion by 29 % compared to samples without this treatment. After quenching and tempering of the borided samples, a maximum tensile strength of Rm = 1779 MPa is measured. Compared to samples which are only quenched and subsequently tempered, this is an increase in tensile strength of about 59 %.

Stress corrosion cracking (SCC) is a common cause of structural failure. The simultaneous action of the corrosive environment and tensile stresses creates cracks that have an intercrystalline or transcrys-talline character. These are cracks with a fragile morphology of the fracture surface without signs of plastic deformation in their vicinity. SCC cracks occur in several alloys. This paper focuses on copper alloys in which this type of failure occurs frequently. Examples from practice show cases where the occurrence of SCC violation was related to the conditions of use of components and their production technologies. The paper does not aim to capture all the influences associated with the occurrence of SCC failure of copper alloy products.

The article deals with the quality of the driving characteristics of a passenger car with passive shock absorbers depending on the tire pressure. The work was solved using experimental methods using the AHS test bench. The main goal of the work was to assess the vehicle suspension system using acceleration sensors and pressures between the wheel and the road using shock absorber test benches using the EUSAMA and CAP methodology. The results of the work demonstrated the possibilities of using the measurement of acceleration values in selected places in the vehicle. The obtained results were also verified for the possibilities of further development in the area of reducing the dynamic load when driving a passenger car on the road.

A model-based viewpoint planning and filtering method is proposed to determine the position and pose of viewpoints in 3D reconstruction of multi-view images. The method first determines the necessary parameters to control the camera position and attitude. Second, the mathematical error model is developed and combined with stereo overlap to guide viewpoint selection. According to the shooting distance, a dense candidate view area is then established, the subview collection is screened, & a view supplement scheme is proposed for the area where the candidate view cannot be shot, improving the integrity of the resulting data. Experimental results demonstrate that our viewpoint planning method has high shooting coverage & highly accurate 3D reconstruction.

In the automotive industry, deep-drawn sheet metals are widely used and protective coatings are ap-plied to its surfaces to improve certain performance properties (e.g. to increase corrosion resistance). Sheets with these coatings are stressed during the forming process of the part and cracking of the protective coating may occur. The main goal of this paper is to determine the resistance of a Zn-Al-Mg based protective coating to uniaxial and triaxial stresses, and also to determine how effective anticorrosion resistance the coating provides to the base steel matrix in the event that cracking occurs. It has been shown that both uniaxial and triaxial loading leads to a failure of the Zn-Al-Mg coating integrity. Salt spray corrosion tests of 3 and 6 weeks were subsequently performed on both deformed and undeformed base material samples. These tests showed that a continuous Al2O3 layer is formed between the steel matrix and the coating, which, irrespective of the formation of cracks in the coating, is the main contributor to the increase in corrosion resistance of the sheet.

With regard to the current economic situation, which deals primarily with energy prices, companies are trying to find reserves within individual technologies. The automotive industry is still a very important industry. One of the ways to improve the material properties of a body part is thermomechanical processing. This is how the B-pillar, which serves as a safety structural element of the car, was processed. The presented article aims to investigate the influence of selected thermomechanical processing parameters on the resulting properties of a B-pillar made of high-strength steel 22MnB5. At the same time, energy saving in the given production process should be used in such a way that it is not at the expense of the quality of the component. Three kinds of experimental production processes with different parameters of thermomechanical processing of steel were proposed for scientific investigation. Based on these proposed processes, several pieces of B-pillars were produced and subjected to further investigation. Changes in material properties were monitored using hardness measurements and subsequently the resulting microstructure of the material was examined for each experimental post.

A considerable attention is paid to the production and monitoring of the properties of metallic cellular structures and the properties of aluminium foams, respectivly. Foam structures can be manufactured in three basic ways (by blowing the external gas into the melt, by melt gasification due to the thermal decomposition of the foaming agent, by the melting of the foamable preform which contains foaming agent particles). The paper addresses to our publication [18] and furthermore focuses on the investigation of mechanical properties of two types of foamed AlSi12 aluminium alloy samples. Samples (150x25x10 mm) were produced by powder metallurgy using a foaming agent TiH2. The characteristics features of the produced foam structures (relative density, porosity, volume fraction of solids, Young's modulus of elasticity) were studied on AlSi12 alloy samples. In addition, the porosity of samples and continuity of their air cells were monitored usign the scanning electron microscope.

Selective Laser Sintering (SLS) or sintering of polymer powders is one of the most well-known additive technologies for printing 3D components. The properties of individual polymer powder materials have a significant impact on the quality of the manufactured part. Potential deformation and shrinkage can occur during printing if a significant number of parts are piled on top of one another or are oriented incorrectly, accumulating thermal energy in certain areas. The aforementioned research focuses on an experimental study to investigate the impact of the distribution and orientation of printing samples in the build chamber on the accuracy of dimensions and the surface roughness of PA12 prints. The aim of the study was to examine the impact of model settings during production as well as the effect of individual factors on the properties of manufactured parts, with a focus on ensuring that heat rises evenly from each print without accumulating.

In today's manufacturing industry, composites are widely used. This is primarily due to the highly variable material properties that can be obtained by combining various materials as reinforcements and matrices. However, modern environmental concerns have pushed researchers and engineers to seek materials from organic and renewable sources. The study will look into composite surface roughness during the cutting process, which will involve milling with a CNC router machine. A portable surface roughness tester will be used to obtain a surface roughness average (Ra) reading, and microscopes will be used to examine the composite surface roughness behaviour under a microscope. Based on the results of the experiment, 82 wt.% vinyl ester resin on coconut fibre composite provides the best material properties. With a constant feed rate of 500 mm/min applied to spindle speeds of 5,000, 20,000, and 30,000 rpm, the 5,000 rpm showed the best surface roughness average performance compared to the other two. Further research focusing on feed rates may be required to better deduce the material machining data.

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.