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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.

The cast Fe-Al-Si type intermetallic alloys (with or without chromium content) were investigated with the aim to obtain the values of thermal expansion coefficient and describe the dilatometric behavior of alloys. The effect of chromium addition, as well as the influence of heat treatment on the structure and dilatometric characteristics (thermal expansion coefficient, CTE), were described. It has been shown that the presence of chromium does not significantly influence the values of thermal expansion coefficient of as-cast alloys so that chromium addition can be substituted by higher silicon content. The annealing used for phase stabilization slightly decreases the CTE values for chromium doped alloys, nevertheless only in the higher temperature range. In comparison, CTE values of the alloy without chromium are slightly increased by the annealing used in the whole temperature interval. But, the differences are not significant from the point of view of technical practice.

The conventional method for measuring propeller geometric parameters involves utilizing specialized equipment or 3D measuring devices. Currently, specific propeller geometry parameters can be as-sessed by employing virtual measurements performed on a virtual propeller model generated using reverse engineering methods. This paper introduces a novel approach to constructing 3D models of small fishing boat propellers using photogrammetry and reverse engineering techniques. In this method, the propeller is captured through photographs taken with a smartphone camera employing special techniques. Subsequently, these images are processed using Agisoft Metashape to generate a mesh model, from which a precise photogrammetric model of the propeller is developed using CATIA. By comparing the photogrammetric model with the scanned model in GOM Inspect, and evaluating the measurement outcomes of blade radius and pitch on virtual and physical models, it is possible to ascertain that the photogrammetric model exhibits exceptional accuracy. Consequently, the photogrammetric model can be effectively utilized for the measurement of propeller geometric parameters.

Today, 3D printed wrist-hand orthoses can be used to immobilize the arms instead of plaster or fi-berglass casts. Typically, 3D arm models for modelling wrist-hand orthoses can be created using a 3D scanning system. Our previous study shows that smartphone cameras and photogrammetry tech-niques can be used instead of professional 3D scanning systems, but the accuracy of the photogram-metric models has not yet been fully investigated. This paper presents the results of accuracy verifica-tion of arm models reconstructed from 2D images captured with a smartphone camera. The forearm and wrist-hand parts of a photogrammetric model were subjected to a virtual inspection by compar-ing them with the corresponding parts of an arm model created with a 3D scanner. In addition, a physical verification was carried out by assessing the contact between the arm of interest and an ac-tual 3D printed wrist-hand orthosis that was created with reference to the photogrammetric model. The test results show that the photogrammetric models achieve the necessary accuracy to serve as reference models for the construction of 3D printed wrist-hand orthoses.

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

Motor rehabilitation contributes to neural remodeling in individuals with motor disabilities, which is crucial for their recovery of motor ability. In addressing the No. of human-machine coupling and synergistic motion characteristics in motor rehabilitation, this study analyzes the collaborative motion characteristics of each joint in the lower limbs. A virtual human-machine coupling system is proposed, and the driving functions of the human-machine coupling system are designed. By utilizing ADAMS motion simulation software, the motion characteristics of the human-machine system are analyzed, and the variation patterns of motion parameters at key positions are obtained. Based on this, the system's synergy is analyzed and experimentally validated from the perspectives of gait, motion speed, and joint motion angles. The experimental results demonstrate that the hip and knee joint angles of the exoskeleton robot exhibit a motion pattern highly consistent with that of the human body, with an angle error of less than 3°,indicating excellent synergy.

The experiments aimed to verify the use of a focused ion beam (FIB) to create structures analogous to the natural surface and then use the two-step imprinting method to prepare replicas of the surface creat-ed by FIB. The surface of the petal leaves of pansy (Viola x wittrockiana) was selected as a natural sur-face pattern. The TESCAN AMBER FIB-SEM microscope was used for the preparation of an analo-gous surface. The molds for the replication process were made of President Light Body elastomer. PVB, PVA, CMC, PCL, EP were used for the preparation of polymer replicas. Scanning electron micro-scope was used to evaluate the quality of the prepared polymer replicas. The dimensions of the replicat-ed convex and concave structures were 25 x 20 µm. The polymers showed a different ability to copy the structure in detail. For PVA, CMC, and PCL, surface structuring at the nanometer level was described in this study. Due to the dimensions of the cones of convex and concave structures, the color was ob-served on all samples.

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

The paper deals the production of porous aluminum materials that are characterized by lower density and mechanical properties. Samples of porous aluminium materials were produced on the basis of the developed methodology that applied sodium chloride particles of different sizes (average size 4, 6 and 9 mm). The AlSi12 foundry alloy was preffered for the production of the aluminium porous material. As part of the experiments, samples of porous aluminium material in the shape of a truncated cone were made. The cavity of the foundry mould was in the shape of a truncated cone with diameters: D = 0.047 m, d = 0.040 m and height v = 0.040 m. The material properties were determined on the produced samples. Their weight, volume and their density, relative density were calculated. Based on empirical relations, their value of Young's modulus of elasticity and value of thermal conductivity were determined. The compressive strength of selected samples was monitored as well. The value of Young's modulus of elasticity was determined from the measured stress-strain course. Furthemore, the porosity of the produced samples was evaluated on a scanning microscope.

Abstract: The article describes a new technical solution for ensuring efficient and inexpensive cleaning, disinfection and sterilization of production facilities and their equipment, based on the principle of gen-erating the use of ozone gas. It describes the technical solution and construction of sterilization and cleaning equipment with ozone gas and the sterilization of small objects, especially textiles contaminat-ed with various viruses, including the Covid-19 virus. The device is designed as energy-saving, structur-ally simple, with high sterilization and cleaning efficiency. The sterilization device is small in size, mo-bile and its design enables transportation in the trunk of an ordinary passenger car. The weight of the device is 14 kg. The device's ozone source is an ozone air purifier, mass-produced according to valid EU standards. The power source of the ozone purifier is an electrical source with a voltage of only 230 V and a frequency of 50 Hz. Alternatively, it is possible to use power from a safe mobile source or inverter. The operation of sterilization and cleaning device in a closed, non-ventilated area, does not endanger peo-ple's health or damage plants. The description of the construction of a technical sterilization device is focused on a specific type of device, but the stated theoretical results can be equally well used in the electrotechnical, food, medical or pharmaceutical industries and in general wherever there is a need to effectively and efficiently clean and sterilize production objects, their equipment, used materials and all other production aids means and tools.

With the development of welding technology and the improvement of automation level, welding robots are playing an increasingly important role in industrial production. However, during the welding process, due to factors such as material characteristics, welding parameters, or improper processes, defects may appear on the surface of the workpiece, which may reduce the quality and service life of the workpiece. In order to solve this problem, this article used frequency domain feature extraction and nearest neighbor classifier in workpiece detection algorithms under machine vision technology to extract and classify surface defect images of workpiece, and studied the detection method of welding robot workpiece surface defects. The research results indicated that, under the same other conditions, the accuracy of machine vision technology was over 90% for all five different defect types, while the accuracy of traditional technology was between 75.5% and 84%. The performance of machine vision technology was far superior to traditional technology, indicating that machine vision technology could improve the accuracy of welding robot workpiece surface defect detection methods.

Nickel superalloys are the main materials used in manufacturing of turbine blades and vanes in aero-space industry. They works is extremely high temperature in a corrosive environment (oxidation, hot corrosion) and undergo several different thermo-mechanical loads. Aluminide coatings are the main method of protection of the surface of nickel superalloys against exhaust gasses environment in jet en-gine. In presented article the microstructural characterization of aluminide coatings produced using two industrial methods (pack cementation and out of pack was conducted. The commercially available powders manufactured by Oerlikon-Metco were used in aluminizing process using industrial Bernex BPX Pro 325S CVD system. The MAR M247 was used as a base material. Amount of activator and pure aluminum had a noticeable effect on the total thickness of obtained layers. Both samples with increased activator and pure aluminum content formed 5 to 11.5 x thicker aluminide coatings in comparison to other sample, which was aluminized using an Al-Co powder as aluminum source. Further investiga-tions are needed to specify precise phase composition of analyzed coatings.

This article deals with adhesion of various alkali-activated metakaolin-based geopolymer coatings on structural steel 1.0038 (according to EN 10025-2). This steel alloy was chosen in order to analysis ad-hesion of prepared geopolymer coatings. Our samples were characterized by laser and SEM micros-copy and grid test was performed. Microscopy was performed to get knowledge about visible charac-terization and overall quality of prepared coatings. Based on previous research SEM results corre-spond with properties changes in coatings and their classification of grid test. Grid test was per-formed and results was evaluated. These results show potential of our prepared GP and could be used as base for further research and possible application as anti corrosion coatings in construction or fire-resistant barriers. The aim of the research was to prepare alkali-activated metakaolin-based geopoly-mer on a structural steel substrate, to evaluate the visual quality of the coatings and to evaluate the results of the grid test.

Nowadays, the digitalization of the production process is an indispensable part of the stampings production in the pre-series stage, but also as a subsequent support for series production. Automotive producers are under pressure to comply with the ever decreasing CO2 production standards for cars, which predicates the use of modern material types with an advantageous weight-to-strength ratio. This paper focuses on the use of mathematical modelling in a numerical simulation environment to predict the deformation process and subsequent material spring-back of dual-phase steel DP500. The material data and characteristics are used to define the material computational model in numerical simulation. The results of the numerical simulations are then compared with the stamping obtained by a real pressing process, where their shape comparison and further evaluation of the used material models and selected parameters are performed.

In recent years, 3D printed arm casts can replace traditional arm casts to treat bones fractures. 3D printed arm cast modelling often uses professional 3D scanning systems to capture 3D data of the arm. These systems are very expensive and may not be available in many hospitals. In order to over-come this disadvantage, inexpensive methods should be developed. This paper introduces a new data collection method based on smartphones. The photos of an arm were taken with a smartphone cam-era using some special techniques that could facilitate the process of image processing and 3D mod-elling in Agisoft Metashape and CATIA. To validate the proposed method, the photogrammetric model was compared with the scanned model (obtained by a low cost scanner) in GOM Inspect. Be-sides, a fit check of real 3D printed arm casts attached on the volunteer's forearm was also per-formed. The test results indicate that the photogrammetric model could be used as raw data for 3D arm modelling.

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.

There are many drawbacks and inconveniences in the application of human power in the energy meter calibration line. In order to achieve a standardized level of operation and to improve the efficiency and quality of the automated meter testing line, this paper applies the intelligent inspection robot to the automated meter testing line and discusses the key technologies involved. Based on the texture characteristics of the screws on the energy meter cover, a screw coordinate positioning method based on the texture center of gravity method is designed as a machine vision technique for intelligent inspection robots. Based on the feedforward controller transfer function and feedback system open-loop transfer function, combined with PI controller, a feedforward-feedback composite servo position control strategy is designed to complete the release action of the robot end controller. Pressure sensor on the robot end claw controller, integrated servo drive with current sensor. The Kalman filter method of static estimation is used to fuse and process multi-source data information to realize the grasping action of the robot end controller. The test results of the key technical performance and economic and time benefits of the robot show that the recognition success rate and grasping success rate of the robot for energy meters are as high as 100%, and it takes a total of 54s to complete each grasping and releasing action. The maximum error in each direction is 4.9mm, 5.2mm and 5.1mm respectively, and the maximum error in angle is only 1.25 degrees. The working manpower is reduced by as much as 93.16%, the average expenditure of inspection cost is only 1.24 yuan, and the floor space is reduced to 700 square meters. In summary, the study can ensure a high level of consistency in the quality of energy meters, improve the efficiency of calibration and production, and create greater economic benefits while providing a solid technical guarantee for the large-scale construction and stable and reliable operation of the power grid.

This research focuses on comparing the working accuracy of two additive manufacturing processes, Atomic Diffusion Additive Manufacturing (ADAM) and Binder Jetting (BJ). Through the analysis of key characteristics of these processes, we aim to evaluate which one yields better results in terms of working accuracy. ADAM is a process that involves the gradual deposition of metallic materials using a plastic binder, whereas BJ is a process where the binder is applied to powder material, followed by the removal of excess binder. This work conducts a detailed examination of the properties of the ADAM and BJ processes, with a focus on surface texture and microstructure of the resulting objects, the use of optimal technological parameters, and the assessment of dimensional and shape accuracy. It is also important to note that the final nature of 3D objects depends on technological parameters such as geometry, orientation, and placement of individual shape specifications. The results of this study are crucial for assessing the accuracy of these additive processes and can serve as a significant basis for selecting an optimal approach in the field of additive manufacturing.

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.

Fused Deposition Modeling (FDM) is one of the widely used technologies of additive manufacturing. The concern over the surface quality and dimensional accuracy is getting increased among the research community. The design of the experimental methodology is based on the analysis of variance (ANOVA) of fractional factorial design. This analysis was used to study the effect of layer thickness, extrusion temperature, speed of deposition, and fill density on dimensional accuracy and surface roughness of the model developed by FDM. Polylactic Acid (PLA) material has been selected in this work as it is inexpensive, easy to print, and biodegradable. The results showed that layer thickness is an effective factor in determining surface roughness. Fill density (X and Z dimensions), layer thickness (Y dimension), and speed of deposition (Z dimension) are significant factors for dimensional accuracy. Regarding surface roughness, curvature was found to be significant; however, the minimum optimization point was not reached. Thus, more experiments are required to be carried out to get the minimum point. For dimensional accuracy optimization, the dimensions along X, Y, and Z were realized to be more accurate at lower levels of every factor except for fill density (D), which was optimized

In warehousing logistics, the sorting and transportation efficiency of goods is still one of the important factors limiting the rapid development of logistics. At present, most regions still use manual sorting with low efficiency and high cost. Especially in some special work areas, such as high temperatures, severe electronic radiation, and areas with heavy long-term work tasks, urgent need for small robots to replace manual labor. In order to solve the inconvenience that small places such as logistics only use manual sorting, It is necessary to design a small-sized weight sorting and transportation robot, which can wait for receiving goods at a designated location, judge and identify the weight of goods by itself through PID intelligent control algorithm, which can move forward at a constant speed, and transport its weight to the designated position and unload it. Constant speed can make the trolley travel more smoothly and load and unload goods more smoothly, which is of great significance.

In order to quickly measure the straightness parameters of the deep hole/blind hole axis, a robot for measuring the straightness of the deep hole/blind hole axis based on the photoelectric prin-ciple is designed. Using the linearity of the laser as a reference, the straightness of the inner hole can be detected through the function that the PSD sensor can accurately locate the position of the energy center of the light. By studying the relationship between the position of the light spot and the output voltage of the PSD device, the measurement model of the straightness of the deep hole axis is derived. During the measurement, the robot spiral driving mechanism moves back and forth inside the deep/blind hole, and the automatic centering mechanism realizes the precise positioning of the deep/blind hole axis. The laser fixed on the axis of the automatic centering mechanism can illuminate the PSD target to obtain the current position data of the deep/blind hole axis. Use the least square median method to eliminate the gross error of the obtained data, and the least square principle fitting can obtain the measurement results of the current axis straightness. In order to ensure the measurement accuracy, the measuring robot is calibrated by a standard ring gauge and used for the age of the pipe with an inner diameter of 135mm to obtain an error accuracy of less than 0.05 mm for the axis.

The features of quality, which is an ambiguous, gradual and very subjective concept, cause that there is no one absolute standard for it. Scientists are looking for ways of its evaluation and improvements of the existing methods. It relates to various areas, but at the same time it is also complex and multi-faceted. There are so many definitions of quality that are constantly evolving. In the paper two meth-ods Servqual and Servperf to assess the quality of teaching services were used. The aim of the paper was to compare the results of the service quality analysis with use of both methods and to indicate the differences between them. It was also checked whether conclusions regarding the quality of ser-vices differ depending on the used research method. The Servqual method takes into account the individual expectations of the respondents, which may affect the assessment of the actual service. It is more complicated, but the results are more adequate to the specifics of the service. It was shown that in one of the areas the results concerning the quality of teaching services differed significantly depending on the used method. However, it is not yet clear which of the two scales is a better meas-ure of service quality.

Nowadays, a lot of data is generated in production and also in the domain of assembly, from which different patterns can be extracted using machine learning methods with the support of data mining. With the help of the revealed patterns, the assembly operations and processes can be further opti-mized, thus the profit achieved can be increased. This article attempts to explore the patterns related to the most used Key Performance Indicator (KPI) in manufacturing, the Overall Equipment Effec-tiveness (OEE) metric. The patterns and relationships discovered will be sorted into Assembly Pattern Catalogue (APC). Firstly, a literature review demonstrates scientific relevance. Secondly, it examines the circumstances and methods of samples in the Manufacturing Execution System (MES) data source and Enterprise Resource Planning (ERP) systems. In the third section, the detailed pattern catalogue is defined in the area of assembly. The novelty of the article is that beyond the generaliza-tion of patterns, it characterizes the pattern catalogue with mentioning practical industrial examples.

The paper deals with a method and technology for increasing of precision sorting of transparent materials - glass. The recycled glass is a valuable material which is necessary as an ingredient in the process of glass manufacturing. We propose a very fast industrial device based on FPGA (field-programmable gate array) image processing along with a novel algorithm for a robust real-time treatment of acquired data. The system consists from a line-scan camera with fast CameraLink interface, FPGA processing, battery of valves propelled via pneumatics and nozzle block. Very important part of the system is a background configuration software enables precise assessment of required limits as inputs to FPGA processing. The overall performance is discussed from the perspective of laboratory and industrial tests. The proposed FPGA image processing can be utilized for further future enhancements in the field of precise sorting of glass with stuck labels on it. The results give very good performance even in the industrial environment with a lot of dust and dirt and hence the glass does not need to be extensively cleaned.

The main idea of this research work is to understand the energy absorbing capacity of cellular solids when used in application of automobile as a safety measure to protect the occupants and structure of the vehicle. The full scaled model of the proposed design of the impact attenuator would be an expensive approach to follow. To understand the mechanism of energy absorption in honeycomb structure two types of experimental test were carried out. The first test includes a simple compression test of honeycomb structure only. The second experimental test consist of a composite sandwich of glass fiber and honeycomb under high speed drop test. Using the simple compression test the mechanical properties of the honeycomb were extracted in the out of plane behavior and then results from experimental data were calibrated with the FEM model. It was observed that very similar results were obtained in Experimental and FEM methods. And finally, the full scaled model analysis was carried in FEM package of ANSYS using mechanical properties of honeycomb extracted in simple compression test.

The article presents results of the use ABC method applied to technological machines modernity level assessment in anti-corrosion protection of steel structures. Research findings enables identifying and analysis of the technological modernity level of machines used in the anti-corrosion protection process that is crucial for the final quality of the process and product manufactured in the steel construction production. The paper proves effectiveness of using ABC method of the machines modernity level as-sessment in the analysis and improvement of the steel construction corrosion ensuring process.

The use of most commercial magnesium alloys is limited to working at normal temperatures. The excellent ratio between the mechanical properties and the density of magnesium alloys necessarily leads to the development of new types of alloys that would be usable even at elevated temperatures. This would significantly increase the applicability of these alloys where steels or aluminum alloys are still used, especially in the transport industry. The problem with today's high temperature resistant magnesium alloys is the need to use expensive rare earth alloys. Significantly cheaper alloys of magnesium with zirconium and calcium are studied in this work. The microstructure, mechanical properties under pressure at the temperatures of 20, 150, 200 and 250 ° C were studied for several alloys with different contents of Zr and Ca. Furthermore, the stability of alloys during their long-term temperature exposure was studied. A very positive effect of the studied additives on the properties of alloys was found, which gives these alloys a very promising perspective in the future.

The article deals with a possibilities of an enhancement of functional properties of highly stressed components by specific combination of surface technology. Two surface technologies such as plasma nitriding and laser shock peening were selected for the experiment. Those technologies were applied upon steel 42CrMo4 frequently utilized in manufacturing of strained components. Properties obtained by applied surface technologies were tested by following experimental methods. The chemical composition was verified by optical emission spectrometer Tasman Q4 Bruker. The surface morphology was inspected by scanning electron microscope TESCAN MIRA 4. The microstructure of heat treated as well as of nitrided specimens was observed by opto-digital microscope Olympus DSX500i. The microhardness profiles were measured by microhardness tester LM247 AT LECO. The friction coefficient was tested on tribometer Bruker UMT 3 TriboLab. For an assessment of the surface wear resistance the profilometer Talysurf CLI 1000 and Contour GT were utilized. The experimental results show that although the proposed surface technology combination manifests itself to be disadvantageous, both technology LSP, as well as plasma nitriding, applied separately, can lead to a significant wear reduction.

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