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The presented article deals with the application of Reverse Engineering and Rapid Prototyp-ing processes in the development process in the automotive industry. In our case, we will focus on the design of the exterior rear view mirror. We obtained the information about the shape and as well as the data used to model the part in a virtual CAD computer environment by scanning it with a Leica laser scanner. The obtained point cloud was imported into CATIA V5 software, which is often used in the automotive industry. In the CATIA software modules, section curves were translated into cloud points. Based on these curves, free shaped surfaces of the mirror body and its holder on the car door were created. After creating the mirror body-mirror mount assembly, print data of these parts were generated for production by Rapid Prototyping technology. The printing method based on ABS material using the FDM (Fused Deposition Modeling) method was chosen.

The presented article deals with the determination of selected mechanical properties of additive ma-terials used for 3D printing (PETG, PLA, ABS, ABS +, PLA ESD, ASA, PC / ABS). Due to the fact that 3D printing has exploded over recent years and additive manufacturing has become popular in some industries, the quality of input materials and their mechanical properties is extremely im-portant. We used 3D printer Original Prusa MK3 to prepare samples for testing. Individual samples printed from all above mentioned materials were analyzed using selected mechanical tests (static tensile test, hardness tests). In the static tensile test, selected parameters (tensile strength limit, ten-sile modulus, elongation) were determined for all additive samples, which were statistically pro-cessed. The parameters for two methods of measuring hardness were also statistically evaluated, namely Shore and ball indentation. All tested additive materials were compared with the aim of ob-taining the final ranking (point evaluation of tested materials with quantification of price costs). The best properties after the performed tests were achieved by the additive material PLA Filament Plasty Mladeč.

Superalloys are a group of alloys developed for use during long-term heat exposure above 650 °C. Properties and applications of superalloys are described in the present work. The work includes statis-tics about superalloys demand, market value and the current price. Division of superalloys according to basic element is mentioned. Nickel-based superalloys are further divided into two groups accord-ing to their use. Afterwards, the paper is focused mainly on nickel-based superalloys. Examples of nickel-based superalloys are listed in the work. Recycling possibilities of nickel-based superalloys are stated and analysed. General scheme of processing nickel-based superalloy scrap with regard to the content of rhenium is proposed and shortly discussed. The best-known companies dealing with sup-eralloy scrap recycling are mentioned further.

High-entropy alloys are known to possed good mechanical properties which are usually related to the preparation technique. In this work, the CoCrFeNiMnXAl20-X (X=5, 10, 15) alloys were prepared by a combination of mechanical alloying (MA) and com-pacted via spark plasma sintering (SPS). Such prepared materials were examined for their phase composition and microstructure. Furthermore, their mechanical properties as a result of the content of Mn/Al were determined. It was found, that the partial substitution of Mn by Al lead to increasing the volume content of the solid solution with BCC crystallographic lattice within the ultrafine-grained microstructure of such prepared materials. Moreover, increasing the Al content within the alloy lead also to the improvement of the mechanical properties. The CoCrFeNiMn5Al15 alloy reached the best properties of all the alloys showing compressive strength of 2496 MPa and having a hardness of 668 HV 1.

Over the next few years, LEDs are likely to be responsible for all of the vehicle's exterior lighting func-tions. Everything is focused on maximum security. For this reason, there are more and more automatic color detection systems in the car. Proper color separation is the key to optimal operation and proper evaluation of these automatic systems. An example is the correct detection of traffic light colors. The automotive industry is dependent on consistency and predictability. Classification is an important func-tion for automated control and requires the correct color resolution of the signals captured by the camer-as. We propose to use glass containing various colored active substances such as Eu2O3, Tb2O3 and Sm2O3 as color filters for LED diodes. LED source from one visible light area to another visible light area. This study is devoted to the production of photoactive glass. Subsequently, the photosensitivity of molten photoactive glasses is tested. Both the absorption and excitation spectra of selected photosensi-tive glasses are measured.

Customer requirements represent the driving force in the market, dictating the directions of development, production and processing of forged parts. Meeting these requirements is of paramount importance to forge shops as a precondition for their continuing operation and competitiveness. Consequently, optimization of manufacturing operations and their rapid response to market requirements are necessary for the forge shops to survive. However, any production stoppage for optimization results in extra costs. Forge shops thus strive to carry out optimization in as few steps as possible and within the shortest possible timeframe. A viable solution emerges in the form of material-technological modelling which involves laboratory-based optimization taking place away from the forge shop without any constraints on the production operations. This paper deals with selection of a material for a forged part to be controlled-cooled from the finishing temperature to substitute a C45-steel part treated by normalizing. One criterion was that the entire forged part should contain ferritic-pearlitic microstructure.

With the rapid development of science and technology, the means of industrial production have become more diversified and intelligent, and the development of new means of industrial production has become an increasingly important research topic. Therefore, the automatic assembly technology was studied taking machine vision system as the main research subject in this study. An automated assembly model of industrial technology based on machine vision recognition was established, parameters such as the part positioning parameter, assembly time, the number of parts wrongly assembled and the number of parts missing and the qualification rate of assembly were obtained, and the corresponding experimental conclusions were obtained. Moreover it was compared with the traditional manual assembly technology, and it was found that the automatic assembly technology based on machine vision recognition had better performance and more remarkable experimental results compared with the traditional manual assembly technology, and the traditional manual assembly technology needed continuous modification and optimization. This work provides a new route for automatic assembly technology in industrial technology.

Multilayer synthetic leather-like textiles are traditionally manufactured by using dimethylformamide as a diluent via polymeric polyurethane coating and coagulation processes. Unfortunately, this process has a strong environ-mental impact since it encompass a complex and polluting grinding process to separate dimethylformamide from water. Furthermore, this compound was proved harmful for both environment and textile practitioners’ health. The aim of this work is to improve the state of the art in the production of leather-like fabrics through the devel-opment of an innovative process of coagulation of polyurethane in aqueous solution to replace the current highly polluting process that involves the use of dimethylformamide. The coagulation is obtained by means of a IR ther-mal fixing thus resulting in a completely eco compatible manufacturing process. The obtained quality of the man-ufactured synthetic leather, tested according to textile standards, is comparable to the one obtained by means of conventional processes.

This article deals with the calculation of pressure vessels for beer maturation using analytical calcula-tion according to ČSN standards and with the help of commercial software PVESS. The article pre-sents commonly used procedures in the design of pressure vessels, resp. vessels for use in the brewing industry in the assembly of pressure vessels stacked on top of each other. The article describes the main parts of the brewery tanks, including the procedure for their design. The choice of materials used, the choice of basic dimensions of pressure vessels was determined in the work. The tank vessel is made of stainless steel 1.4301 or 1.4541. The advantages of this material in the brewing industry are also presented. From the given input parameters, a control calculation of the strength of pressure vessels was performed. The result of the work was the verification of the calculation, finding out the deviations of the measurements using mathematical software with a common calculation according to the valid standards for the calculation of pressure vessels.

A number of asset management models, methodologies and tools are available and well known today. How-ever, various organizational approaches to asset management processes are adopted by companies in the industry. In the paper, a number of examples of maintenance process models are summarized and a comparison of examples (benchmark) of real maintenance organizational structures is presented. The used examples origin from chemical, petrochemical and automotive industries. On this background, a case study of major maintenance organization change in Unipetrol, a central European refinery and petrochemical group (part of PKN Orlen) is presented and analysed. The goal of the implemented changes in the company was to increase the overall efficiency of the maintenance organization, mainly in the areas of management, and to achieve the set KPIs. Organizational changes were implemented on the basis of a model of a close connection between maintenance and production organizations in the form of a Multi-profession production team, named “Facility team”. The changes in the organisational structure and asset management processes described in the paper had finally a significant impact on the number of management positions (reduction by 25%), roles, competencies and asset management process flow. The quantitative impacts to KPIs in areas fulfilment of process safety requirements and efficiency, after implementation this changes, it had a positive effect in the horizon of the coming year and are also evaluated and analyzed in the paper.

Technological progress in the 21st century has catalysed the industrial revolution (Industry 4.0) following the development of multiple new industrial automation technologies in the manufacturing sector. Regardless, past research indicated the unsuccessful attempts in adopting Industry 4.0 technologies among manufacturing organisations. Undoubtedly, the operationalisation of Industry 4.0 in manufacturing proved challenging as organisations were required to evaluate various aspects for effective implementation. Thus, a sound understanding of constructs concerning employees’ acceptance and readiness levels towards novel automation technologies was required. Hence, this study aims to explore, develop, and validate the suggested conceptual framework by integrating the Technology Acceptance Model (TAM) and Technology Readiness Index (TRI) with Exploratory Factor Analysis (EFA). The EFA process was the first crucial step in ensuring the internal consistency and stability of the instrument across the sampling population. Consequently, the research outcome potentially enabled the manufacturing sector to identify and comprehend the key determinants in designing industrial automation technologies. This study also contributed to knowledge on technology acceptance by synthesizing TAM 3 and TRI 2.0 theories, thus constructing a new TAM in manufacturing.

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

The present contribution examines the structures of and corrosion processes in copper-basalt composite laser claddings on a steel substrate. The cladding material was a laboratory mixture of the following components: Oerlikon METCO 55 (Cu > 99.9 %) + basalt dust. In this investigation, metallographic structures of copper-basalt composite laser claddings were studied using optical and scanning electron microscopy. The adhesion of the claddings to the substrate was testing using the non-standardized Mercedes test. A potentiodynamic corrosion test in artificial mine water was performed on a specimen of the composite laser cladding. The test results were compared against those for a reference high-purity copper standard and AISI 304 steel. The findings were interpreted in terms of the potential of using copper-basalt composite laser claddings as corrosion protection coatings on steel components in nuclear power generation.

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

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

The article presents new possibilities of simulation software and its application to improve the pro-duction structure. In many enterprises, the basic issues are related to the determination of planned tasks for individual positions, calculating the demand for employees, taking into account their skills and qualifications, calculating work costs, determining work efficiency and its dynamics. Therefore proper work organization consists in setting the course of work in such a way as to obtain maximum results with the least amount of work by man and machine. The article presents the problem of per-sonnel allocation to the production line. The basic stages of developing a simulation model of this process are discussed, including all necessary information and inputs. The results shows impact of the selected simulation scenarios to the workload level of the staff and the duration of the production process. In this concept, to solve the problem a simulation model of the production process was built. A new generation of 3D FlexSim simulation environment with an integrated OptQuest optimi-zation module was used.

The article deals with the design of a robotic workplace for laser engraving. The first part of the article describes the importance of introducing robotics to industry 4.0. Custom solutions work is devoted to the implementation of the six-axis robotic arm UR10. This six-axis robotic arm inserts the designed jig with the semi-finished product into the engraving machine. In the engraving machine, the semi-finished product is engraved on the final product. This saves the operator time to pinpoint the position of the semi-finished product inside the engraving machine. The proposed jig is designed to be universal so that the position in the x-axis and in the y-axis can be precisely defined. At the end of the jig there is a bed for placing the semi-finished product, which can be replaced by another in the case of other dimen-sions of the semi-finished product. The conclusion is a comparison of time savings in individual steps and overall engraving time savings for one engraved part.

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

The article presents the results of the use of quality instruments – tools and techniques – in order to reduce surface defects of steel structures on the example of a selected element – engine cover of asphalt milling machines. The article shows the potential of using selected quality tools – basic and new – in the service of quality analysis and improvement. Quantitative analyzes were presented out using the Pareto-Lorenz diagram and the c control chart, qualitative analyzes using the Ishikawa diagram and the FMEA method, quantitative & qualitative analyzes using the interrelationship diagram and matrix diagram, and it was proposed quality improvement using qualitative tools such as affinity diagram, and PDPC diagram. The most common defects of painted surfaces turned out to be improper thickness and surface contamination. As it has been shown, the experience of employees is largely responsible for the cause of these defects, which was also confirmed by other analyses carried out with the use of quality tools. The training was the most frequent method of prevention. It has also been shown that special attention should be paid to quality control, its effectiveness, and quantity. The article proves that correctly used quality tools can contribute to the improvement of the quality of manufactured products, helps in solving various quality problems.

Tool life changes according to a curve presenting two extreme values depending on the cutting speed. Besides the well-known Taylor formula, several other functions describe tool life, mainly for the 3rd speed range beginning with a tool-life maximum. In earlier studies the authors suggested a tool-life function valid for the whole speed range. Here the machinability of hardened steel is being investigated in a wide range of cutting speeds. The intention of this study is to work out a method for the physical interpretation of tool degradation defining the tool life. For this purpose the nonlinear differential equation of wear rate is applied. During the experimental work the tool life was measured when boring a 100Cr6 hardened workpiece of 75 mm diameterin the speed range vc=10…120 m/min with a feed rate of f=0.075 mm/rev, depth of cut ap=0.1 mm, γr=-5° and the life criterion Wcr=0.4 mm. The results proved the supposition that at a speed smaller than the tool-life maximum it is abrasion and adhesion that causes the tool deterioration, while above this speed, the thermo-activated degradation process plays an increasingly large role as speed increases. Calculating from the results of the cutting examination, the activating energy of the degradation process is Q=136±29 KJ/mol, on the basis of which it is likely that the degradation of the tool material occurs through the recrystallization of the surface layer from cubic into hexagonal, causing the surface layer to wear out more rapidly.

The paper deals with the physical-chemical effects of a blowing agent on production the cellular metal systems (in this case aluminium foams). Based on the isothermal concertation and pressure curves for the H-Ti system and by using the maximum gas volume obtained from equation of state, there was applied the blowing agent to 1 kg of AlSi12 aluminium alloy. Moreover, using relation to determine aluminium foam relative density (ρ REL) from alloy AlSi12, there was done prediction to determine density of 1 kg metal foam from AlSi12 alloy at different blowing agent contents from 0.1 up to 1.5 wt% of titanium hydride TiH 2. These isothermal calculations were compared with the density of aluminium foal from alloy AlSi12, which was produced by an industrial process. Basic mechanical properties were subsequently measured on the produced foam samples.

This paper presents the theoretical calculations of the foaming process of selected powder foaming agents (TiH2, CaH2, MgH2, ZrH2, CaCO3 and MgCO3) regarding the volume of gas, relative density and density of the metal foam obtained with respect to the use of a certain amount of powdered blowing agent. This work is carried out in the frame of the university project in which a small subproject is dealing with the problem of the cellular lightweight metal structures. Furthermore by calculating the diffusion of hydrogen in both solid and liquid aluminium there were found results for the duration of the anticipated action of the powdered blowing agent (0.75, 1.0, 1.25, 1.50, 1.75 and 2.0 wt. %).

Our workplace, Technical University of Liberec, is currently engaged in research and production of cellular metal systems. Basically, cellular metal systems are materials with lower density. It is a research in the field of mechanical engineering that is focused on the development of new materials. In general, many methods have been developed for the production of cellular metal systems, e.g. by BANHART [2] or ASHBY [4]. At their production, the direct gassing of molten metals (mostly aluminium ones) or gassing by the powder agents (e.g. specially formulated aluminium powders) are mostly used. Depending on the manufacturing method, a cellular system with open or closed cells can be obtained. The most commonly used metal is aluminium and its alloys. We are currently focusing on the production of porous aluminium by using sodium chloride. Sodium chloride occupies regular sites in the aluminium material and thus contributes to the aluminium porosity. After solidification of the aluminium, sodium chloride is dissolved in water. Sodium chloride is relatively inert to the aluminium and together with it, has a favourable density (2160 kgm-3) compared to the aluminium density (2700 kgm-3). The values of these physical quantities were observed on the produced aluminium test specimens having  60 x 10 mm: relative density of porous system REL; porosity of metal system P; amount of solid phase system volume fraction VPM; density of porous metal system PM and porous material Young's modulus of elasticity EPM.

At the present time, mechanical vibration is undesirable in many cases. Therefore it is necessary to minimize unwanted vibrations in any appropriate manner. This paper is focused on a study of factors influencing vibration damping properties that were investigated using multilayer composite structures. Frequency dependencies of the displacement transmissibility over a frequency range of 2?1500 Hz were determined by the method of forced oscillations. It was found in this study that the vibration damping properties of investigated multilayer structures are significantly influenced by number of material layers, excitation frequency of mechanical vibration, applied materials in multilayer structures, inertial mass, material thickness and density. It was also observed that a superior ability to damp mechanical vibration leads to a shift of the first resonance frequency peak position to lower excitation frequencies.

The article deals with geopolymer binder system for core production and comparison with PUR cold box amin technology. A sodium-potassium type of geopolymer binder is the subject of the research. The goal of the article is the core production and observing of technological properties, storing cores, usage of refractory coating evaluating of properties during the pouring and decoring of casting. The main target of the experiment is casting quality. It was stated that the final surfaces are much more better than PUR cold box amin technology and the internal casting quality is the same, it means without inadmissible internal defects. Worse decoring times were observed. It has been confirmed, that neither emissions, fumes nor unpleasant odours are generated during the production procedure nor during pouring.

This paper deals with the use of lean manufacturing methods to streamline the welding line in the au-tomotive industry. The automotive industry is constantly developing and innovating its production envi-ronments and technology because of growing competition on the market and customer demands. Cur-rent trends of car makers include pressure to reduce costs and increase production efficiency. With the commencement of new technologies, the production lines began to innovate and the production cycle began to constantly accelerate. The paper deals with the reconstruction of the welding line, which produces parts for the rear axle of a compact SUV. The case study aims to identify bottlenecks and set innovation plans and their evaluation in possible implementation. In the paper, lean manufacturing methods are applied in order to deter-mine the ideal solution for ensuring the quality and ensuring the efficiency of the production line, lead-ing to cost reduction. Through these innovations and modernizations, the company will be heading for digitalisation that changes the core of the industry.

Currently, companies have been trying to make the use of their technology, manufacturing capabilities and experienced workforce to respond flexibly to market demands. Collecting and processing of all relevant data in the company is one of the key points to which increased attention should be paid so as to maximize the efficient use of own resources and consequently ensure a continuous reduction of pro-duction costs. The article deals with the use of burning machines in engineering company. The product range involves the production of burnouts from standard and special materials as well as welded steel parts of structures. The company has long struggled to optimize the material and information flow between particular production operations. This paper was focused on information flow logistics, which proved to be the biggest weakness of the central material preparation department during the bottleneck analysis. The scientific contribution of the resolved issue can be seen mainly in the possibility of inter-connecting process analysis and optimization of material and information flows.

Very dynamic development in the field of computerization and industry robotization, as well as an im-plementation of the Industry 4.0 assumptions are the main reason for the increased demand for magnetic materials. The limited rare earths availability and the sustainable development in the field of material engineering indicate that the methods of recycling magnetic materials from Waste of Electrical and Electronic Equipment are necessary. This paper presents the impovement stages of magnets recovery process - extrusion process of magnetic scraps/particles with polymer (magnetic scraps and particles obtained from WEEE). The process is developed based on the Process Failure Mode and Effects Analy-sis. The reserch pointed the irregularities, that pose the greatest risk of failure in the process. The paper presents changes in the process based on the values of the indicators: severity (S), probability of occur-rence (O), probability of detection (D) and the Risk Performance Number (RPN). Based on the PFMEA, 5 operations were added to the process. Due to changes in the process course, it is possible to minimize the effects of the irregularities occurrence.

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 article deals with the design optimization of the mechanical crank press. These presses have not any signifi-cant development changes in a long time. Mechanical press LDC 250 with nominal force 2.5 MN (250 tons) was considered as an example. This type of press can be used for operations such as bending, drawing or cutting. The topology optimization was used during this research. This papers show advantage of this design method. The op-timized press has lower maximal Von-Mises stress in the structure and the maximal displacement is up to two times lower. The research was focused on the main frame (open frame with shape ?C?) of the press. The resistivity aga-ings vibrations was improved. The weight of the frame was not changed. The CAE tool NX Nastran and the opti-mization tool Frustum were used here. The workflow of the topological optimization is deeply described here. The comparison between the conventional (initial) and optimized design shows new approach to these machines.