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With increasing complexity of machinery and products manufacturing the strict requirements for quality and, reliability of the measurement equipment and systems plays significant role in production system and quality assurance in terms of customer satisfaction. In nowadays automotive industry in connection to ISO/TS 16949:2009 there has been observed a strong confrontation with request for proof of suitability for use of selected gauges for a specific operations. An appropriate methodology allowing to determine a gauge the most suitable for a given operation is Gauge Reproducibility and Repeatability study (GRR or R&R). The GRR takes into a consideration the variability of produced parts, operator`s approach, and whole measurement system. The article deals with a description and the adequate methodology, and the experimental implementation of GRR in manufacturing quality process assurance in order to set up and continuously improve the quality level in automotive parts production.

Integral stringer panels can attain weight reduction in primary aircraft structures, but do not contain the physical barriers for a fatigue crack growth. One of the promising techniques for prolonging a fatigue crack growth is bonded crack retarders made of materials with high stiffness. An experimental study was done on two specimens with different geometries. High strength bonded straps made of corrosion resistant steel AISI 301 were adhesively bonded to Center-Cracked Tension (CCT) specimens made of aluminium alloy 2024-T351 and fabricated by a high-speed machining process to promote fatigue crack growth retardation. Specimens were tested at a constant amplitude load. The study concludes that the fatigue crack growth life can be significantly improved. Experimental results were compared with a prediction based on the VCCT technique and the NASGRO equation.

Aiming at the problem of product family assembly line (PFAL) evolution balancing, an evolution balancing model for PFAL is established and an improved algorithm based on NSGA_II is also proposed. Firstly, the product family evolution and assembly line characteristics are researched and analyzed in big data environment. Tasks on PFAL are divided into platform and personality tasks, and the stability of assembly tasks is mainly considered especially. In the optimization process, a chromosome encoding based on TOP sorting algorithm is adopted, and a new density selection and decoding algorithm is proposed to make up for the deficiencies in traditional algorithms. Finally, an example of PFAL planning is given to verify the effectiveness and feasibility of the improved NSGA_II.

This paper deals with the preparation, composition and mechanical resistance of inorganic-organic nanolayers with built-in hydrophobic groups through sol-gel synthesis. The components of the nanolayers are 3-(trimethoxysilyl)propyl methacrylate, tetraethyl orthosilicate and hydrophobic chains - hydrocarbon chains in the range of 8 to 16 carbons. The study is aimed at evaluating the mechanical properties of prepared nanolayers with different hydrophobic chains compared to a reference sample without any hydrophobic groups. An abrasion resistance test was performed on several selected nanolayers with the best hydrophobic and antifouling properties. In the framework of the research, nanolayers prepared with polymerization achieved by heating at 85 °C or 150 °C were compared. The best mechanical properties and hydrophobicity of prepared nanolayers was AF12 with a hexadecyl hydrocarbon chain polymerized at 150 °C. These nanolayers are suitable for marine, underwater or any other hydrophobic application results from performed research.

The abrasive wear of pulley surfaces at winding of the ropes causes changes of the shape and quality surface of the groove and has influenced lifetime of the skidding machine. The pulley is made of steel C45E without heat treatment and its structure is not suitable for the abrasive wear of the pair metal-metal. Contribution describes a research aimed to changes in material structure by the heat treatment. The pulleys (first one in original state and second one after heat treatment) were tested in operating load at skidding during 320 hours. After experimental test, measurable properties as weight loss, groove dimensions of the pulleys were compared. On the samples from the pulleys, material resistence to wear was tested too. Another alternative for change of material properties would be an aplication of various types of weld deposits on the steel C45E. We have examined the quality of weld deposits and compared their hardness and microstructure. The results of experimental tests resulted to recommendations for practice.

The present work deals with the execution of through micro-holes on tungsten carbide plates using a micro-EDM (Electrical Discharge Machining) machine. The investigation focuses on the monitoring of the performance during the drilling phase in order to obtain the in progress behavior of the performance indexes. The experiments were carried out by varying some process parameters such as peak current, voltage and frequency to achieve both high and low power discharge conditions. Regarding electrodes, the most commonly industrial used ones were selected: tubular tungsten carbide and brass. The performance indexes taken into account were machining time, Material Removal Rate (MRR), Tool Wear (TW) and Tool Wear Ratio (TWR). Brass electrode always resulted to be the best solution in terms of drilling speed even though the wear of this electrode type is remarkable higher than the tungsten one. The evolution of the performance indexes during the drilling operation showed the same trend for both electrodes: increasing the hole depth, the drilling operation proceeds in a more difficult way, due to the evacuation of debris that becomes more difficult and therefore the performance indexes get worse. Finally, the technology windows of the cumulated MRR and TWR were defined for both electrode materials, in order to predict the micro EDM process performance varying the hole depth.

The works deals with a study of fillers influence on chosen mechanical properties of polyamide and the given influence was investigated by using of atomic force microscopy (AFM). Atomic force microscope NT-206 in a complex with control and image processing software is intended for measurement and analysis of surface microrelief and submicrorelief, objects of the micrometer and nanometer range with high resolution. Using AFM it is possible to scan spectroscopic curves that show dependence of composite action force of the probe and surface of the sample on distance between them - they are curves of approach /moving off. In presented measurements by using of spectroscopic curves, the homogeneity and ratio of Young's modulus for polyamide samples were evaluated. For each sample, the curve was created by using of five different places - points. We employed the general approximation and Snedonn's formula for analysis of data and calculation of Young's modulus off complete rake curve. The Sneddon's model gives the relationship between load gradient dP/dh and Young's modulus E.

Seamless tubes are the strongest amongst all tubes types and have a homogeneous structure throughout their length. They are typically manufactured by cold drawing where strong grain deformation takes place. EBSD was used to evaluate the changes of grain structure and texture connected with tubes manufacturing from the initial state over the cold drawing with a stationary plug to subsequent recrystallization annealing.

At present, a large spectrum of cutting tools and machines is available. Therefore, cutting of difficult to cut materials seems not to be a problem which could not be solved by an appropriate choice of cutting system. This article deals with wear of cutting tool edges when milling a superalloy Inconel 718 and its direct influence on resulting roughness of a machined surface. Combinations of different cutting speeds and feeds have been performed. A criterion of flank wear amounting to VB=0.7 mm was chosen for machined material Inconel 718 and used cutting materials in combination with cutting conditions. Regarding the exacting character of the test it was necessary to use an as solid as possible machine, that is why a 3-axis CNC milling machine was chosen. All tests were performed with process liquid because of extremely high temperatures which occur.

This article deals with the experimental grinding of cemented carbide cutting tools. Several carbide milling tools with the same geometry were ground under the different grinding conditions and strategy described in this research. The main aim is to determine the influence of the grinding process on the quality of the cutting edge. Different grinding conditions and strategies were used in grinding of the primary radial relief on the peripheral cutting edge. The cutting edge was analysed after grinding by an optical-scanning device and an electron microscope to determine the quality of the cutting edge and radial relief face of the tool. EDX analysis was used for the chemical characterization of the ground surface. The chipping of the cutting edge occurred when the grinding feed rate and the wheel spin direction was changed. The influence of the grinding conditions and strategy on the chipping formation was determined. The mean radius of the cutting edge after grinding was also measured. The results of this work will be used for further research and cutting experiments.

The need to determine actual fiber volume ratio of the real composite part manufactured in the semi-closed mold led to application of the alternative procedures than the widely used Burn-off method. The low cost one, which is required preferably by any manufacturer, is based on Archimedes law (AL) and the most accurate determination of volume of displaced water. The more complex method which is based on the reverse engineering approach where the 3D scan technique is used to determine the volume of the part. Both are nondestructive methods. And finally the last method mentioned in this study is a sophisticated optical visualization technique and Figure post-processing by mathematical software (it was used NIS Elements and Wolfram Mathematica). Figures for mathematical post-processing were taken using light optical microscope (LOM) and scanning electron microscope (SEM). While better contrast between matrix and fibers is achieved in case of composites filled by transparent fibers, SEM figures provide better image contrast for non-transparent fibers.
The AL and 3D measurement methods are very precise and suitable for orientative control during production, but they give only an average values of the fiber volume ratio in whole product. The mathematical post-processing of image is suitable for laboratory designing of composite part. It is destructive investigation method and image thresholding is time consuming, but on the other hand image processing gives the resultant fiber volume ratio in a particular cross section of the part. That makes the technique a good tool to find the weakest place of the part in meaning of the mechanical properties.

This work deals with the possibility of modification of the phase composition and improvement of the properties of the NiTi alloy by alloying with other elements. After the production by conventional melting metallurgy as well as powder metallurgy, the Ni-Ti alloys contain in addition to the NiTi shape memory phase a lot of other phases, for example Ti2Ni, Ni3Ti, Ni4Ti3. Some of these phases can have an undesirable effect on the properties of the Ni-Ti alloy. A possible solution is the addition of alloying elements to destabilize these phases. The aim of this work is to describe the effect of Zr, Nb and Cr as alloying elements in the amount of 1 and 3 wt. % on microstructure, phase composition, hardness and transformation behavior of the Ni-Ti alloy produced by powder metallurgy using reactive sintering. Alloying by chromium leads to increase of hardness and microhardness of the NiTi phase whereas the addition of the alloying elements niobium and zirconium increases the temperatures of phase transformations.

This paper deals with numerical simulations and with experimental testing of chassis of low-floor trams. This chassis was designed with respect to low-floor construction, low weight, good driveability of a tram and with respect to fulfillment of standards and regulations. The chassis is in a numerical simulation burdened by load conditions according to EN 13749:2011 even during an experimental testing. The simulation is performed using the FEM Nastran solver implemented in the CAD system Siemens NX 11. Based on FEA the locations for strain gauges during testing were found. A total number of 40 strain gauges were used to measure the strain which was then recalculated to uniaxial stress. The testing was performed on hydraulic test bench Inova. The results of FEA and of an experimental testing were compared.

In the current world, the business faces different challenges, as it was in the 1950th. Today, most of the manufacturing companies have a very strict approach to increasing market needs of Safety, Quality, Delivery and Cost key performance indicators (KPI). To stay competitive, it is needed, that a holistic approach on the improvement of strategic KPIs is needed in order to be successful. The target of this paper is to show the application of the Value stream mapping methodology, used in a case study for a finish good assembly line in an Electronic Manufacturing Facility. The study is showing the improvement of quality, delivery and productivity KPIs over a time period of 3 consecutive years. The result is the increase of production output from 500 pcs/shift to 1050 pcs/shift, decreasing the number of quality returns from 3 to 0 and improving the delivery performance from 95 to 100% against customer requested date.

Polymer composite honeycomb sandwich panels (PCHSPs) are used in many sectors of industry, such as in aerospace, defense and public transport factory. Sandwich panels consist of two facing skins and the core. Products of all industry sectors have to meet requirements on their dependability. This research paper deals with a proposal of the most appropriate methodology for dependability testing of PCHSPs products used in transport industry. Dependability is a global concept that includes terms such as availability, reliability, durability, maintainability, supportability, etc. The experiments have shown S-N curves with damages and without damages of PCHSPs. An important part of dependability is to be fonded the limit states of the studied object, which are for PCHSPs are characterized by fiber cracking and (core) delamination. Dependability evaluation consists of analysis and tests. For every test, it is necessary to be developed its test plan. Facing skin components of the sandwich panels may particularly be damaged. There are several methods of non-destructive testing, which can be used to determine the damage of facing skins of sandwich panels. Infrared thermography (IRNDT) is one of them. IRNDT utilizes thermo-physical properties of the materials, including thermal diffusivity.

Hot dip aluminizing of steel products leads to the contamination of the batch by iron, which could significantly exceed its admissible levels. The re-processing of thus-polluted Al-Si waste by conventional casting technologies requires extensive technological adjustments, which raise the cost. Therefore, powder metallurgy was used to process Al-Si15-Fe7 alloy (in wt. %) to refine the microstructure and improved mechanical properties without further modification of chemical composition. Mechanical machining (MM) followed by spark plasma sintering (SPS) led to strong improvement of ductility, whereas mechanical machining coupled with high-energy ball milling (HEBM) and consolidation by SPS resulted in compressive strength reaching almost 1000 MPa, but with the absence of plastic deformation. In addition, both samples showed no significant change in mechanical properties even after long-term annealing at 400 °C.

In order to solve the problems of data collection, data storage, artificial neural networks, real-time display of images, real-time monitoring of current status and recurrence of historical data, online monitoring system of cold extrusion of internal thread process is designed by LabVIEW8.5. The time-domain analysis and time-frequency-domain analysis are carried out for the torque signal, temperature signal, vibration signal, acoustic emission signal and transmitted signal. The research shows that: this online monitoring system can forecast processing status accurately, raise real-time alarm to replace or re-install the thread forming tap, accordingly avoids effectively the wreckage of thread forming tap and the scrap of work pieces; the fault recognition rate reaches 97%. And the practical model of online monitoring system for cold extrusion of internal thread process can be used to monitor working process.

This work deals with the microstructure of TiAl15Si15 intermetallic compound, which can be used as a high-temperature low-weight material especially for the automotive and aerospace industry. A combination of high mechanical properties, good oxidation resistance and low density of this material is a good potential for use this alloy in many applications. The TiAl15Si15 alloy was prepared by different techniques of powder metallurgy. In this work, microstructure after reactive sintering, reactive sintering in a combination of Spark Plasma Sintering and mechanical alloying followed by Spark Plasma Sintering was described. The results were compared with the same alloy prepared by arc melting.

Titanium aluminides represent a class of materials with unique mechanical and physical properties. This is reason why they are often used in aerospace or automotive industries. These materials form lamellar or nearly lamellar TiAl and Ti3Al phases. There are few methods how to synthesize Ti-Al based alloys, but they are often very difficult and expensive. In present work, a mechanical alloying which is probably best choice for synthesizing of Ti-Al intermetallic phases was used. Further, the most promising conditions of mechanical alloying allowing to create intermetallic phases were determined. It was shown, that by mechanical alloying allows to synthesize desired alloys with grains sizes of several tens of nanometres.

The rolling process is widely used to manufacture high-performance splined shaft components. However, there is a convex at root on free end of spline formed by rolling with round dies. However, the analysis and representation of this forming problem are difficulty due to the complexity of motion and multiplicity of processing parameters. This paper concentrates on the corner filling problem, and a physical analog experiment was designed to investigate the problem. The physical experimental results indicated that the designed experiment can reflect the formation of convex during spline rolling process. The finite element analysis of the physical analog experiment process was carried out to study the influences of friction condition and end shape of billet on convex at root of rolled spline. The results indicated that the height of convex will be reduced with increasing friction condition; the height of convex can be reduced by optimizing the end shape of billet. The results of present study provide a basis for optimizing and controlling the forming quality on free end during spline rolling process.

The article deals with the optimization and modernization of assembly systems by creating models in the simulation software. The creation of digital models is a current trend in enterprise digitization called Industry 4.0. The Tecnomatix Plant Simulation environment allows you to create a virtual model of a real assembly line with the input of its basic production parameters. To perform the analysis, 8 real assembly lines were used, with an average of 15 workplaces, which were integrated into one universal line by means of simulation. The aim was to analyse the effectiveness of the proposed modernization universal assembly line using the generated statistical data.

One of the basic principles of railway vehicles is their carrying and guiding. In the contact pair of a wheel and a rail, one body is rolled on the surface of the other part and all main forces are transmitted in this contact. Contact between wheel and rail is also important from an economic aspect as it is related to the wear of the track rails and the wheel thread itself, including the wheel flange, and has caused the necessary maintenance of the track and the vehicles themselves. Therefore, our article focuses on simulating the influence of a flat wheel on changes in wheel forces. The model was created in the CATIA program and was consequently imported into the SIMPACK program, which was followed by analysis of the passage of the vehicle along the track. In the simulation, we considered an ideal track and a wheel flat on the right front wheel. We also plan to work with these results by adding and comparing them with results obtained by applying irregularity to our ideal track.

Cutter vibration characteristics of five-axis milling machine in high-speed milling process were studied. Finite Element Modal Analysis for high-speed cutters with different parameters is conducted using finite element software.The impact of tooth number, extended length, diameter and material of milling cutter on the mode shapes and natural frequencies of milling cutter is researched in detail. Harmonic response curves of High-speed cutter under different frequency are calculated. Based on the response curve, the resonance frequency range of high-speed cutter is obtained in order to achieve high-precision milling and longer life of the tool. Analysis shows that: mode shapes of milling cutter are divided into strong vibration mode shapes and weak vibration mode shapes and its natural frequency become smaller with the increase of the cutter teeth number. Natural frequency of milling cutter decreases with the increase of extended length of milling cutter. The number of strong vibration mode is smaller with the increase of milling cutter diameter so that the milling cutter with large diameter can play a role of anti-vibration. Natural frequency of the high-speed steel cutter is lower than that of the diamond and carbide cutter. This research provides theoretical basis for the design of high speed milling cutter and reducing milling chatter.

The article describes the fundamental physical principles of the ultrasonic defectoscopy Phased Array, which provides new possibilities in the non-destructive testing (NDT) of materials, especially of welded joints. There is a report from the ultrasonic testing of welded joint with ultrasonic flaw detector OmniScan MX2 from the company Olympus NDT. The artificial defects were designed in software ESBeamTool 5 from the company Eclipse Scientific, which simulates the geometrical ultrasonic beams spread. Then, ultrasonic testing was performed at the same welded joint with artificially made defects. At the end, data from both ultrasonic testing were evaluated. The same procedure will be used for the design of ultrasonic inspection TOFD (Time of Flight Diffraction) and Phased Array at welded joints of gas pipelines.

The article describes mathematical model and possible usage of results of dynamic loading simulation of the chassis of track vehicle. The computational model is designed for computational simulating system MSC.ADAMS.AVT. Possibilities of research results usage are described in the article mainly. Results of simulation calculations were used for make-up of constructional parameters parts file of vehicle chassis and findings of influence their changes on changes of directional vehicle stability by running at first. Make - up of approximate relations for transaction of fast orientation calculations is second described possibility of results simulation calculations usage. The possibility of usage of results simulation to do verification of mathematical model is third possibility of usage results simulation calculations. The optimization of influence changes of several design value together is fourth possibility of usage of results simulation calculations that is described in this article.

This article focuses on an analysis and a transfer process of CT clinical metadata of a real patient gained within a cooperation, research and development of an individual knee joint implant at Clinique of Display Methods in Saint Anna's Teaching hospital in Brno. The first part of the article is aimed at the application of a software 3D-DOCTOR that enables gaining of demanded output data (e.g. a model of patient bone part, i.e. knee joints) from scanned input CT metadata in DICOM format (Digital Imaging and Communications in Medicine). The output data are gained in format *.stl (Stereo Lithography) to further possible usage (e.g. a design and a production of individual total joint prosthesis). The second part of the article concentrates on an application of software RP MiniMagics that enables editing, modification and the whole optimization of polygon net by which models of distal part of femur and proximal part of tibia are described.

The final shape of machine parts is formed out by means of machining. At the machining the surface rises of definite properties, a given integrity, from these a surface usage comes out in the final machinery. This surface use is put especially its service life and loading capacity. The manufacturing watches the selected elements of the surface integrity for the functionality assurance of the machine parts. The machining influences in a different way the variant components. These are e.g. construction notches - the changeovers of single design components. The selection of a technology method of machining, the cutting tool at the finishing can affect notably both the function and service life of a machine part. The paper deals with the surface integrity at the surface load in machinery. There are the questions of the construction notches and next elements owing to the use of finishing method.

The design of elliptic trajectories of kinematic mechanisms by classical method is a challenge. New method is proposed. Theoretical tests were conducted on a method. It can not be used for scaling and rotation. Some limitations are revealed as well. Geometric modeling showed the method can be applied to arbitrary curves. It should be noted that the theoretical and modeling researches of arbitary curves is not full. Simple robot was designed for processing ellipses. The design of the stand was assembled from aluminum profiles, linear modules and fasteners RK Rose + Krieger. Experiments have shown a difference between the theoretical and actual trajectory less than 5%. The error of stationing was 8,5% before using of the direct analytical method.

The article focuses on the issue of 3D measuring surface parameters using optical measuring devices, designing a statistical experiment and following evaluation. The development non-contact surface texture measurement methods lead to new possibilities for describing the surface of machine parts. But cannot be to rely only on the obtained the measured parameters values, and it is true that it is necessary to prepare the measurement. The processes of measurement enter many influences. Some of these effects can manage it, and then we call those factors. At the output of the receive process feedback. Method DOE (Design of Experiments) is used to locate a combination of factors that provide the most favorable response. The proposal described experiment compares and evaluates various surface roughness parameters of two different materials and machining technologies samples. Measurements were done by two operators, and each measurement was carried out three times. Measurement took place on a confocal laser microscope LEXT OLS 3000.

The article describes the fundamental physical principles of the ultrasonic defectoscopy TOFD (Time of Flight Diffraction) and Phased Array. There is a report from the ultrasonic testing of girth welded joint with ultrasonic flaw detector OmniScan MX2 16:64 PA from the company Olympus NDT. In welded joint were artificaly made three defetcts. Two lack of sidewall fusion (on the left and right side of welded joint) and one crack in axis of welded joint. Both ultrasonic testing were designed in software ESBeamTool 5 from the company Eclipse Scientific, which simulates the geometrical ultrasonic beams spread. At the end, data from both ultrasonic testing were evaluated. The same procedure will be used for the design of ultrasonic inspection TOFD and Phased Array at girth welded joints of gas pipelines.