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Monitoring and diagnostics of cutting tools are crucial for ensuring production efficiency and product quality in the machining industry. This study uses acoustic emission (AE) to non-invasively detect damage and monitor tool condition in real time. Experiments assessed cutting inserts in a milling head, both used and new. Results showed AE effectively diagnoses tool wear, with significant differences in signals from worn and new inserts. Fast Fourier Transform (FFT) analysis determined the frequency range of signals during machining, confirming AE's usefulness. Microscope verification supported the AE findings on tool wear. This research highlights AE's potential in non-destructive diagnostics, enhancing production efficiency and product quality

The Mg-Y-Zn alloy system is well known for its outstanding combination of high strength and ductility, even at relatively low concentrations of alloying elements. This exceptional performance is primarily at-tributed to its characteristic microstructure, which features Long-Period Stacking Ordered (LPSO) phas-es and the distinctive Mille-Feuille Structure (MFS). Kink-induced strengthening, developed during thermomechanical processing, has emerged as a promising strategy to simultaneously enhance strength and ductility. In this study, the beneficial effect of pre-deformation aimed at introducing additional kinks into the microstructure prior to extrusion is demonstrated. The subsequent extrusion process promotes dynamic recrystallization (DRX), generating fine DRX grains while preserving kink structures in the non-DRX regions. As a result, the yield strength is enhanced by approximately 80 MPa, accom-panied by a slight improvement in ductility.

As part of my research work, in its practical part, I deal with the selection of suitable 3D printing pa-rameters for parts of a robotic kit, as well as the selection of a 3D printer and the determination of a set of experimental measurements and testing in order to obtain the necessary data to determine a suitable filament material for 3D printing of a part of a robotic kit and setting the appropriate 3D printing parameters to obtain the desired mechanical properties of the parts while maintaining the economic benefits of 3D printing. The main aspects for choosing a filament material are printability in primary and secondary school conditions, easy printing (beginner level), minimal postprocessing, adequate mechanical properties – these are obtained by experimental measurement and correspon-ding destructive tests on a real part from the VEX GO and IQ kit.

Titanium is the polymorphic metal whose recrystallization temperature significantly affects its final properties. The area between 850 °C and 995 °C is a very important area from the point of view of heat treatment of titanium alloys. It is a transition area just below the β transition limit. This article deals with the analysis of the influence of thermal loading on the change in tensile strength and fracture behavior of titanium alloys in comparison with thermally unloaded samples. Monitoring of fracture surfaces and description of the internal structure of the material.

When diamond scribing knives are used to grind silicon wafers at ultra-high speeds, slight changes in the structure of the diamond scribing knives and changes in the grinding parameters will have a large impact on the processing accuracy and appearance of the silicon wafers. In order to reduce the defective rate of silicon wafers, improve the service life of diamond scribing knives and grinding efficiency. To address this issue, the working mechanism of the scribing knife grinding is analysed in the paper, the influence of spindle speed and feed rate on the quality of the silicon wafer slit when the scribing knife is grinding is studied, and the chipping of silicon wafers is observed through the scanning electron microscope and optical microscope, so as to analyse the shape of the cross-section, length of the cutting edge, concentration of diamond particles in the cutting edge, thickness of the cutting edge and determine the structure of the scribing knife, and to test its influence on the silicon wafer slit by means of the grinding experiments. The structure of the scribing knife was determined, and its influence on the quality of silicon wafer slit was tested by grinding experiment. The results show that the wear rate of diamond particles, slit quality and processing efficiency of the scribing knife are optimal when grinding silicon wafers at 50,000 r/min and 60-80 mm.sec^-1. The above study can help to further understand the wear mechanism of the scribing knife in the process of ultra-high-speed grinding of silicon wafers, improve the machining efficiency, and prolong the service life of the tool.

In order to solve the problem of heterogeneous deformation in the rolling process of 10Ni5CrMoV heavy plate, the effects of uniform temperature rolling (UTR) and graded temperature rolling (GTR) on the microstructure and deformation uniformity of 10Ni5CrMoV steel were studied by means of numerical simulation and verification experiment, and the strengthening mechanism of high permeability rolling process on the rolling deformation of 10Ni5CrMoV heavy steel was clarified. The results show that compared with the uniform temperature rolling process(UTR), different gradient temperature rolling processes (GTR) make the deformation area gradually expand to the core, and the deformation of the core increases significantly. The reduction rate of the first pass gradient temperature rolling processes (FGTR) is about 2.3% higher than that of uniform temperature rolling, and that of continuous gradient temperature rolling (CGTR) is about 5.3% higher than that of uniform temperature rolling. At the same time, the microstructure difference of the core surface is reduced, which is conducive to improving the uniformity of microstructure and properties. At the same time, the microstructure of the core in the rolled is uniformly refined, and the effect is significant.

To enhance the accuracy of fault diagnosis (FD) in motor rotor systems, this study introduces a novel method that leverages feature extraction (FE) combined with a CNN-BiGRU-Attention deep learning model. Initially, the time-domain features of the vibration signals are extracted using Variational Mode Decomposition (VMD), which also effectively denoises the data. Subsequently, the frequency-domain features of the vibration signals are extracted via Fast Fourier Transform (FFT). The aggregated features are then fed into the CNN-BiGRU-Attention model to perform fault classification. In this model, the Convolutional Neural Network (CNN) module extracts local spatial features, the Bidirectional Gated Recurrent Unit (BiGRU) module models the temporal dependencies, and the Attention mechanism enhances the focus on critical fault information, thereby improving the model's classification performance. Experimental results demonstrate that the proposed FD method achieves an accuracy of 99.58%. Compared to other commonly used models, the performance metrics of our model show significant advantages and superior performance.

Tree-like branched Al-Al₂Cu heterogeneous nanostructures with a high surface area ratio were successfully fabricated using magnetron sputtering of Al matrix and Cu nanoparticles, followed by in situ annealing. The method enables precise control over the composition and morphology of the nanosized columnar Al₂Cu phase grown on the substrate and embedded in the Al matrix. The formation of Al₂Cu begins at the initial locations of sputtered Cu nanoparticles. Further annealing promotes their coalescence and coarsening. Orientation relationships examined in several Al₂Cu particles revealed a semi-coherency with the Al matrix. The high surface area and tunable composition highlight the potential of these nanostructures for advanced battery anodes, with tailored geometry achieved through controlled processing conditions.

The introduced work deals with the microscopic analysis of metallographically prepared selected metal materials structures, using a scanning electron microscope (SEM). Prepared samples of seamless steel pipes were subjected to a thorough microscopic examination from the outer surface to the inner regions in order to interpret the spe-cific structure, including the change of the inner surfaces due to wear. The experiment showed that the micro-structure and character of the surfaces play a crucial role in the behavior of metallic materials under real condi-tions. Four types of pipes were monitored according to their use. The unused steel pipe (designated as sample No. 1) exhibited a rough outer surface with identified inclusions, while the used pipe (designated as sample No. 2) showed marks of intergranular corrosion and significant wear after long-term use. The older pipe (designated as sample No. 3) showed a decarburized area and inclusions containing sulfides and aluminum. The steel pipe with corrosion layers (designated as sample No. 4) exhibited a continuous corrosion layer with cavitation and cracks. The results of this study offer a comprehensive view relating to the influence of the nature of the micro-structure and wear on the water flow (performance) of metal pipes, with an emphasis on the identification of possible risks associated with geometry change, corrosion and wear. The recommendations create a basis for predicting the degradation as well as appropriate maintenance to ensure their long and reliable service life under real-world conditions of use.

Cast iron with nodular graphite is one of the most important structural materials that exhibit really good mechanical properties already in the as-cast condition. Nowadays, cast iron with nodular graphite is used in many areas of the manufacturing industry, the most widespread being in the engineering and automotive industries. The applicability of this material for construction purposes is mainly due to its mechanical properties, which are close to those of steel, but the production cost of cast iron is lower. This experiment was aimed at optimizing the production of ductile iron castings in the casting pits so that the foundry could produce ductile iron castings in the casting pits. Therefore, the optimization of the moulding compound database material was carried out in numerical simulation and at the same time, the heat transfer measurement of the foundry sand mould was carried out.

The effective application of additively manufactured materials requires accurate identification of their mechanical properties as well as damage mechanisms. Computer vision offers a novel approach for non-contact measurements, enabling the identification of selected mechanical properties. This paper presents a new method based on image analysis and the detection of circular markers for non-contact displacement measurements. The core principle involves detecting the centers of gravity of the circular markers formed on the sample under investigation. The centers of gravity are evaluated on each image created during the tensile test, representing nodal points. At these points, displacements are determined based on the non-contact extensometer. The deformations sought are a function of the displacements at each nodal point. These values were calculated based on several theoretical models, also used in the finite element analysis. The paper describes the computational procedure for determining the deformations based on the mentioned theoretical models. Subsequently, the total strain field is determined using linear interpolation of the displacement values at the individual nodal points. The results provided by each of the theoretical models were compared.

In order to explore the causes of trapped oil and cavitation formation during the operation of aviation fuel gear pump to ensure the safe and reliable operation of the pump, dynamic grid technology and Realizable were adopted. The k-ε turbulence model and Schnerr-Sauer cavitation model were used to simulate the three-dimensional transient state of the jet fuel gear pump. The results show that: 1) the air bubbles are mainly distributed in the tooth cavity of the inlet end of the gear pump due to the low inlet pressure and the vortex. 2) Under the effect of high pressure and bubbles at the outlet, an approximately closed tooth cavity is formed near the outlet end, and the trapped oil pressure is generated, whose pressure value is 16 times that of the inlet pressure. 3) As the outlet pressure decreases, the trapped oil pressure in the tooth cavity decreases, but the area of the low pressure area increases, and the cavitation area shows a diffusion trend. 4) The high pressure value formed in the tooth cavity is mainly affected by the speed of the gear. As the speed decreases, the high pressure value gradually decreases to the outlet pressure, and the pressure value decreases slowly with the change of the rotation Angle; The speed decreases, cavitation weakens and the cavitation bubbles formed in the tooth cavity gradually shrink to the oil film between teeth.

Molten salt reactors are one of the technologies developed under GEN IV nuclear research. The mol-ten mix of LiF and BeF2, LiF, NaF nad KF, or NaBF4 and NaF act both as a reactor coolant both in primary and secondary loop. The combination of molten fluorides and high temperature creates high-ly corrosive environment. The aim of this work was to test corrosion resistance of Inconel 800HT alloy in molten FLiNaK, FliBe and NaBF4-NaF mix. The testing tube was filled with salt mixture and heated to 600-725 °C for a total of 1800 hours. The material exposed to NaBF4-NaF mix shoved mild corrosion attack on grain boundaries. Samples exposed to FLiNaK salt were more damaged, largely the part above the salt surface. The intergranular corrosion was also observed, more severe than in the case of NaBF4-NaF environment. Corrosion in the FLiBe salt caused depletion of alloying metals from the material’s surface. In all cases was dissolving of Cr into the melt identified as the main mechanism. The corrosion was accelerated by impurities in the salt mix, mostly water forming hydrogen fluoride gas in combination with insufficient seal of the testing tube.

The topic of this paper is the application of machine learning and neural networks in engineering, specifically in the prediction of the lifetime of bearings operating in different conditions. In addition, the basics of machine learning are introduced, giving an idea of the importance of input data quality for model training. It also presents the elements of neural network training to be used in other projects. The article is supplemented by a source code examples written using only the Python language, and some other popular libraries, like the NumPy, Matplotlib, Tensorflow, Keras, and Scikit-learn. The main advantage of the libraries used is that they are freely available and widely used, bringing variety of sophisticated tools for gen-eral use.

Workpiece fabrication of titanium alloy is widely used in several high-end fields. In this study, finite element analysis of titanium alloy turning process is carried out and the turning process is modeled by using material properties and intrinsic equations. Then the power transmission of centerless lathe is controlled in the machining process, so as to obtain the performance calculation of different process parameters on cutting force, chips, and residual stress. The analysis of the simulation and experimental data yielded that when the tool travel speed was 1 m/min, the radial force increased to a maximum value of 150N. When the depth of cut was 0.3mm, the radial force was 151N and then increased to 200N. In the comparison of the simulation results, it was concluded that the depth of cut was 0.3mm, the minimum error value was 7.43%. In the quality analysis, the optimum parameters for travel speed and depth of cut were 1.0 m/min and 0.2mm respectively. When the spindle speed was 480 r/min, the roughness of the machined surface of titanium alloy was closer to the simulation results, and the lowest difference was 0.1 μm. Therefore, the finite element machining model of titanium alloy turning proposed by the study could effectively improve the machining quality and accuracy, and it has superiority. In the future machining and parts manufacturing, it can improve the processing efficiency and promote the optimization of titanium alloy material properties.

In the automotive sector, poroelastic materials (PEMs) are used as trim elements to achieve the desired interior acoustics of a vehicle. This study examines the effect of manufacturing as well as measurement techniques on airflow resistivity. This property plays a key role in the acoustic behavior of PEMs. First, the importance of engineering acoustics and poroelastic materials in vehicle industry is reviewed, followed by the introduction of the most important properties and their measurement techniques. Next, the theory and the measurement techniques used to determine resistivity via direct method are detailed. Then the factors influencing the results and their quantified effects are presented. More than 10 influencing factors are identified and examined, from which the inhomogeneity, resulting from the production technology proved to be the most significant. The results obtained with direct and inverse methods are compared for validation purposes and to determine the achievable accuracy of the inverse method. The average difference between the two methods is 4.54%, which means that the inverse method can provide a good approximation. Finally, conclusions are drawn and suggestions are made for the future.

In this study, the ballistic resistance of multi-layered composite armour is experimentally investigated. The composition of this armour consisted of armour steel Armox 500T, para-aramid fabric Twaron CT 747 and ultra-high molecular weight polyethylene Endumax Shield XF33. To compare the ballistic resistance, the ballistic resistance of the armour with the perforated steel Armox 500T was tested. The rifle cartridges 7.62 x 51 mm FMJ NATO M80 were used to test this resistance. The aim of this experiment was to compare the ballistic resistance of unperforated and perforated steel Armox 500T. As part of the experimental part, the chemical composition and microhardness of the steel Armox 500T was verified. The hardness of the composite materials was also measured for optimal armor configuration. After the projectile impact, the damage mechanism of the steel Armox 500T and the composite materials were investigated by using optical and electron microscopy. It was proved that the ballistic resistance of the perforated steel depends on the used pattern. Based on the performed experiments, the steel Armox with pattern A effectively reduced the weight of the testing configuration and absorbed all the kinetic energy of the projectile 7.62 mm FMJ M80.

In order to improve the crushing effect of the rotor of vertical shaft impact crusher on the particle, the design method of secondary accelerated rotor based on kinematics theory is proposed. And the operation effect of the secondary acceleration type rotor was verified using a combination of computational fluid dynamics and discrete element method (CFD-EDM). First, the kinematics of the particles thrown by the rotor throwing head was analyzed. On this basis, the structure of the secondary acceleration type rotor was designed by comprehensively considering factors such as the motion, friction, and collision recovery coefficient of particles; Then, based on the gas-solid coupling analysis method, a simulation model of the rotor's effect on particle acceleration was established and the reliability of the model was verified; Finally, the CFD-EDM method was used to calculate and analyze the motion process of particles in the crushing chamber, the collision position of particles in the crushing chamber, and the average throwing speed of the rotor. Research results show that roughly 77.6% of the particles in the crushing chamber will collide with the impact plate to achieve secondary acceleration; The average throwing speed of the traditional rotor is 57.14m/s, and the average throwing speed of the designed secondary accelerated rotor is 60.89m/s, which is about 6% higher than the average throwing speed compared with the traditional rotor, and achieves the expected design purpose.

The present paper is focused on the study of the characteristics of selected titanium alloys before and after heat treatment. The specimens were cooled both in water and liquid nitrogen from 900°C and 1000°C for pure titanium and from 1000°C and 1100°C for the Ti-6Al-4V alloy. Further, the paper deals with line MG63 live bone cells deposited on a titanium base substrate. Proliferation and differentiation are monitored of cells during 7-day in vitro cultivation portraying growth of cells on a biologically selected material.

Titanium alloy Ti6Al4V fabricated using Selective Laser Melting (SLM) has gained significant attention in biomedical and aerospace applications due to its superior mechanical properties and design flexibility. However, its machining characteristics, particularly in milling, remain challenging due to the material's hardness and thermal conductivity. This study investigates the milling performance of SLM-manufactured Ti6Al4V by optimizing surface roughness using the Taguchi method. An L9 orthogonal array was employed, considering spindle speed, feed rate, and depth of cut as control factors. Surface roughness measurements were analyzed using Signal-to-Noise (S/N) ratios, and Analysis of Variance (ANOVA). Results indicate that spindle speed significantly affects surface roughness, contributing over 83.67% of the total variation. The optimized milling parameters resulted in a notable improvement in surface quality, highlighting the effectiveness of the Taguchi method in achieving better machinability for additively manufactured titanium alloys. This study offers useful insights to improve the milling process of SLM-made Ti6Al4V, helping boost performance in industrial use.

Externally toothed components have a very crucial and essential role in all areas of production and manufacturing because they function as away of transmitting motion, energy, and power in all indus-trial applications, such asmodes of transportation, aviation, aerospace, equipment, and operating machines like lathes and milling. All machines have a gear box. Therefore, it is receiving increasing attention. This research presents a new multi-stage rotary ballizing technology for producing toothed parts in one stroke. This process has been investigated experimentally. The parameters that were ex-amined experimentally was at the optimal conditions for single stage ballizing were: die rotation speed of 315 rpm; Axial feed rate, 0.13, mm/rev; The interference (cross in-feed) between the balls and the tubular specimen of 5.5 and 6.5 mm is formed by three stages of ball forming of graduated outer diameters and fixed on a single mandrel; Initial tube thickness is 7 and 8 mm. The effect of these parameters on the forming load, filling ratio and quality of the formed part was studied. The finding sindicated that the seideal variables influence the forming load, tooth filling proportion, and product quality. Experimental results proved the success of this novel technique to form toothed tubular components

The three-point front-mounted electric forklift is an important logistics tool nowadays. The wheel-side reducer is a vital power unit of the electric forklift. The cover plate of the reducer casing, as a key component, bears significant external loads. The cover plate of the casing is prone to deformation under the action of loads, leading to part scrapping and reducing the service life of the entire machine. Additionally, as the cover plate directly connects with the vehicle body, vibrations produced by the electric forklift during operation can affect the working stability of the reducer through the cover plate, reducing its lifespan. When designers design the wheel-side reducer cover plate, they first establish a 3D model of the cover plate using Pro/E. Then, the 3D model is imported into the finite element analysis software ANSYS. By integrating the Newton-Raphson iterative method, the cover plate undergoes static analysis, predicting potential design flaws and proposing corresponding optimization strategies. After several rounds of simulation and optimization, the cover plate meets the usage requirements. Through modal analysis, the inherent frequency of the cover plate is determined. This allows for the assessment of the relationship between the working frequency and inherent frequency, thus facilitating the improvement of the cover plate's design parameters to reduce resonance and noise. Through static and modal analysis, not only is the design cycle of the reducer cover plate shortened and production costs lowered, but resonance is also minimized, enhancing the working stability of the reducer.

This paper proposes a set of stable auxiliary positioning modules for die-cutting shoe material by means of image-based die-cut calibration. Used in combination with a self-developed polygonal-object packing system for shoe-material cutting, the punching machine tool can automatically cut accurately, stably, and efficiently with the highly integrated hardware and software. In particular, the packing of the shoe material is based on the contour of the die-cut mold vector, and the object-dilation method is used to maintain a fixed gap between the objects. Then, a search method is employed to calculate a compact packing of the die-cut contours. The center point and azimuth angle of the die-cut contours are determined through object packing by a heuristic search. The contours of this die-cut are projected directly onto the positioning module. The physical die-cut mold is aligned with the images, and then the die-bar is locked to complete the die positioning, which is synchronized with the packing system. This new die-cut calibration method is more accurate and reliable. Moreover, the error in the gap between the material and the die-cut was ±0.1 mm, which is in line with the development trend of automatic precision die-cutting.

The aim of this study is to investigate the effect of oscillatory loading frequency on the dynamic-mechanical properties of 3D printed thermoplastics, namely acrylonitrile-butadiene-styrene (ABS), glycol-modified polyethylene terephthalate (PETG), and polylactide, also known as polylactic acid (PLA). The investigated samples were manufactured using fused filament fabrication (FFF) technology and tested at different oscillation frequencies (1, 5, 10, 15 and 20 Hz). Dynamic mechanical analysis (DMA) demonstrated that an increase in the oscillation frequency causes an increase in the glass transition temperature (Tg) for all analyzed materials, while in the case of the used loading frequencies above 5 Hz, an almost linear dependence between the magnitude of the applied frequency and Tg was observed. The findings also show that with increasing frequency of mechanical loading, there are changes in the visco-elastic properties of the investigated polymers, specifically in the value of the storage modulus (E′), loss modulus (E′′) and loss angle (tan δ), which points to the complex behavior of the materials under dynamic conditions. The results of this study provide valuable insights for the use of 3D printed polymer materials in applications where they are exposed to dynamic stress - in the automotive or aerospace industries.

Core-shell powders have been extensively studied due to their complex structure and wide range of applications. W@Ag core-shell powders are particularly interesting due to the synergy between the tungsten and silver, which can be beneficial in the electronics industry. However, knowledge of their thermal stability is limited, particularly concerning the impact of annealing temperatures on structural integrity and oxidation resistance. In this work, W@Ag core-shell powder was heat-treated in the temperature range 100–700 °C for 1 h in air. Investigation of the microstructural changes using scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy showed that the limiting temperature is 500 °C, when the shell began to decompose and the core began to oxidize. Moreover, X-ray diffraction analysis determined that the phase composition of the thus heat-treated material consisted of approxi-mately 50 % Ag and 50 % Ag2WO4.

Wire electrical discharge machining (WEDM) was employed to process thin-walled, multidirectional carbon fiber-reinforced silicon carbide (Cf-SiC) composites. This study investigates the effects of key WEDM parameters, including gap voltage (Vg), pulse on-time (Ton), pulse off-time (Toff), and wire electrode type on material removal rate (MRR) and surface roughness (SR). All experimental planning, data analysis, optimization, and result visualization were conducted using MATLAB software. Results indicate that using CuZn50-coated wire electrodes increases MRR by 11% compared to CuZn37 bare brass wire. Scanning electron microscopy (SEM) confirmed the inverse thermal expansion-based material removal mechanism, revealing surface defects such as fiber fractures, interfacial detachment, craters, and micro-cracks. Surface roughness, as indicated by 3D topographic measurements was found acceptable with an average Ra between 2 and 3 μm. Overall, WEDM proves effective for machining Cf-SiC, especially for complex geometries such as holes, grooves, keyways, and splines when appropriate electrodes and parameters are applied.

The paper presents the analysis of the gantry crane loading when driving along the crane track, using a Working model 3D, for which the analysis of the gantry crane frame loading was performed. The gantry crane is designed to remove dirt in front of the turbine under the water surface. For the gantry crane which moves along a track, the directional and vertical unevennesses were determined by experiment and are given in graphic and numerical form in (mm), relating to A track and B track with a total track length of 450 (m). Based on the knowledge of the unevenness of the rail track, the four random functional dependencies defining the irregularities of the individual rails as input variables were used for the kinematic excitation of the individual wheels of the gantry crane. The stress analysis was performed for a travel speed of 30 (m.min^-1) and a lift of 10 (t) under the given loading. The results of the stress analysis are presented in graphic form.

X-ray diffraction (XRD) is an analytical technique used to investigate the crystal structure properties of materials. However, the accuracy of XRD measurements can be significantly affected by the sam-ple's surface preparation. This study evaluates the impact of various surface preparation methods on the diffraction peak characteristics, phase composition, and residual stress analysis of two metallic materials: very low alloyed iron-based alloy labelled as pure iron and hardened 54SiCr6 steel. Various final steps of metalographic preparation of the surface for XRD were used, including mechanical grinding with coarse (P120) and fine (P1200) sandpapers, polishing with OPS colloidal silica, chemical etching in hot hydrochloric acid, and electrolytic etching. The results show that surface conditions influence more on the full width at half maximum (FWHM) than the intensity of diffraction peaks. Furthermore, the annealed pure iron sample (with low hardness) exhibited a more pronounced sensi-tivity to surface preparation compared to hardened 54SiCr6 steel, with its martensitic microstructure. Residual stress analysis using the sin²ψ method further revealed that mechanical grinding induces substantial compressive residual stress while polishing and etching methods produce nearly neutral or slightly tensile residual stresses. These findings highlight the importance of consistent and appropri-ate surface preparation methods for reliable XRD analysis.

This study presents a systematic experimental analysis of vibration responses in a planetary gearbox (type A2000) under both undamaged and artificially induced fault conditions. The primary aim was to identify specific frequency-domain signatures of various types and severities of gear defects—such as pitting on the flanks of gear teeth, missing teeth, unbalance of the carrier, and damage to the ring gear—through spectral analysis of vibration signals. Measurements were conducted in both loaded and unloaded states using non-contact torque sensors and a multi-channel diagnostic system (SKF IMx-S) with tri-axial accelerometers. The results demonstrate a strong correlation between the severity of gear damage and the amplitude and structure of sidebands around the gear mesh frequencies. Notably, the presence of pitting consistently increased the sideband amplitudes, while unbalance induced distinct harmonics in the frequency spectrum. Damage to the ring gear and central gear exhibited overlapping features but were distinguishable in the acceleration envelope spectrum. The findings provide a foundation for the early-stage identification of gearbox faults and highlight the potential for deploying automated diagnostic systems in industrial applications. Future work will focus on real-time AI-based detection methods and application of the results in industrial environments such as Continental and U.S. Steel.

The Ti-6Al-4V alloy is widely used as a material for medical implants. In the future, it may be employed for 3D printing using the selective laser melting method. The advantages of 3D printing are for example production of complex shapes or ability to create customized implants. One of the disadvantages of this method is the deterioration of mechanical properties, particularly the ductility of the alloy, caused by high residual stress resulting from rapid cooling during printing. This article aims to characterize the microstructure and defects of the printed alloy and the impact of hot isostatic pressing. Optical microscopy, scanning electron microscopy, and micro-computed tomography were utilized for the study. It was found that the heat treatment has a significant effect on the pore size and microstructural transformation. These findings could lead to the optimization of the manufacturing process and improve the quality of implants made from this alloy.