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The paper presents the strength tests results of joints made by use of two hot melt adhesives. The tests were carried out according to the modified standard ČSN EN 1465 (66 8510) and ČSN EN 205 (66 8508). For bonding the three-layer plywood of 4 mm thickness was used. The test samples of 100 x 25 mm size were cut out from a semi-product in the direction of its longer side, in the oblique direction and in the direction of its shorter side. The specimen pairs were bonded using the hot melt glue gun. All assemblies were loaded up to their destruction. The destructive force and the destruction type were registered. From the results of carried out tests evaluation it follows that hot melt adhesives can be recommended for bonding plywood. The bonding strength of bonded joint is comparable to the strength of the bonded material. Finally the technical-economical evaluation of the experiments was carried out.

The paper deals with welding joints and the methodology of increasing safety during austenitic chromium-nickel steels welding - type EN 10028-7 1.4301 (X5CrNi18-10). The technology of submerged arc steel welding 1.4301 using MAG enables a wider application of these steels in terms of the production of pressure vessels, but despite following all the safety regulations of heterogeneous welding stated in WHS, there might be an occurrence of melting defects of carbon parts through the welding of joints. The aim of this paper is to discuss the corrections of welding penetrations of the additional material during inhomogeneous welding, with the least possible destruction of the original material.

A properly designed and engineered gating system for use with high pressure die casting technology will produce castings with excellent mechanical properties. The gating system must secure the fast and continuous filling of the cavity. An appropriately designed and structured gating system can reduce the length of the die casting process, thereby increasing the effectiveness of production, reducing the amount of waste, and delivering cost savings. This article focuses on the structural analysis and optimization of runners and their impact on the mould casting of a specific light-weight casting made of AlSi alloy.

This paper deals with the creation of a computational model of a particular cable manipulator composed of a rigid manipulator with three degrees of freedom and a platform driven by four fibers. Each fiber is led over a pulley and is driven by a linear motor, which can be controlled. The multibody dynamics approach is a suitable way in order to create the manipulator model. The most common cable modelling techniques are summarized in this paper and then the computational model of the cable manipulator QuadroSphere is created using MSC.Adams software. The computational model verification is done using the modal analysis of linearized model and the experimental modal analysis on the real set up. Further results of various numerical simulations are presented and their utilization is discussed.

This paper presents a new computer-aided method for modular-fixture design, in which the key point is building the fixture on the concept of NC Manufacturing System (NMS). In this paper, an approach of creation for a NMS is proposed, first to extract or setup the feature model of worktable of NC machine tool in any CAD system. Base on the worktable, the algorithm of computer-aided modular fixture design (CMFD) is then presented; the Post-NC verification to check the performance of modular fixture in NC machining is introduced at the last section of the paper. This method could help engineers to develop and employ an error-free modular fixture during the complex NC-manufacturing production.

Article deals with the during operation of pneumatic dosing device designed for die casting machines where the metal level in the furnace decreases stepwise by which the period of dosing of the filling mould is prolonged. We also deal the regulation of delimitation of metal level decrease in the furnace based upon the pneumatic principle.

Nowadays, there is a huge number of machine tools of various damage degree all over the world and it is necessary to renovate them. Some parts can be renovated by the adhesive bonding technology. However, it is necessary to quantify the degradation process. The aim of experiments was to set the influence of cutting fluid on the strength changes of adhesive bonds. In cases of satisfactory results it is possible to use with success the adhesive bonding technology for the renovation of damaged parts of machine tools. On the basis of the performed experiments it can be said that the resultant strength of adhesive bonds decreases during the time at simultaneous acting of the cutting fluid. From the experiments results the same influence on the degradation process of various adhesives was not proved. It came to a stagnation of the adhesive bond strength decrease after 75 days on the average.

With development of a number of branches (automobile industry) the demand of increasingly more complex and more exacting castings that are mechanically cleanable with difficulties only is growing. Application of the technology of disposable water soluble cores from inorganic salts is one of solutions of troublesome problems of removing the cores from places hardly accessible for cleaning. Solubility in water enables reversal crystallization of the salt from the water solution what is a precondition for forming a closed ecological cycle of the core manufacture. Application of salt cores can be met in processes of low-pressure casting, gravity casting in dies, and in connection with just running research project in pressure castings from Al-alloys. The article brings results of checking the cores made from cooking salts (NaCl) predominantly available on the Czech market. It is aimed at two main technologies (shooting and high-pressure squeezing) of their manufacture and it investigates the influence of chemical composition, form and morphology of the grain surface on mechanical properties (bending strength) of water soluble salt cores for their application for high-pressure die casting of Al-alloys.

The main aim is testing the basic properties of cobalt super alloys, under its own brand name HAYNES, marking No. 188, at machining and propose the most suitable cutting materials and machining parameters. The superalloys are developed for elevation of temperature service where relatively severe mechanical stressing is encountered and high surface stability is frequently required. The cobalt-based alloys have been in use for several decades in the manufacturing of various components. Although technology development rises in chipless machining such as moulding, precision casting and other manufacturing methods, the machining is still number one, at piece production which is typical for energy and chemical engineering. The driving force for their development still has been requirement of higher operating temperatures for many manufacturing fields in industry area.

Extraordinary properties of magnesium alloys, biodegrability and low density guarantee that these alloys are suitable for using in medicine as bone implants. So far there have been used alloys of titanium, cobalt and stainless steel for this purpose. Among the mentioned materials the magnesium alloys are winning because of their mechanical properties, which are more similar to human bones and at the same time there is the possibility to reduce the number of surgeries because of the spontaneous implant disintegration. Pure magnesium reaches neither the requested mechanical properties nor the corrosion resistance. That is why people are searching for elements, whose supplement would improve these magnesium properties to acceptable values. In this paper there was examined the influence of alloying elements (zinc, yttrium) on mechanical properties, the shape and the size of pores in the structure of magnesium alloys. Apart from alloying elements, a pores creating agent was also added to create pores with the diameter of more than 200 μm in the structure of magnesium alloys. Pores of this size allow the bone cells to grow in the implant and enable its gradual replacement by the bone. All samples were prepared by the method of powder metallurgy.

The study aim was discussion on the steel construction production with regard to quality problems and its analysis by using value engineering. The most important elements of the work should, however, discuss how an important factor for the company's production and quality management are. Based on this explicit purpose developed the following hypothesis: identification of the nonconformities location in the production process of steel constructions and its causes contributes to the production improvement. The research result is identification of nonconformities formation areas and presentation of the production process improvement methodology by applying of quality tools and value engineering idea as well. The research object was chosen company producing steel constructions for buildings. The examination research findings come from 2011 year.

This paper presents static measurements results of the kinematic pair centre of the C-rotary axis of the 5-axis machine tool at digitised angle positions αof the machine rotary table. The measurements were conducted with the application of R-test calibration and measuring system. The article discusses the test sequence as well as the evaluation of the kinematic centre location of the rotary axis, relative to linear X, Y-axis. The summary formulates guidelines covering the compensation of the axis location. Measurement results were presented in diagrams and tables.

Objectives of the paper are intended to implement system solutions to nondestructive evaluation of technologies associated with verification of equipment, preparation of samples with different types of functional properties and their subsequent evaluation of various scientific methods. The main objective of experiments is to transform new knowledge of non-destructive technologies into industrial practice in the evaluation of functional properties of the surface and subsurface layers of these technologies. The aim is to increase the level of cooperation R & D institutions with social and economic practices through knowledge and technology transfer, and thus contribute to increased economic growth of the regions in Slovakia. This work is related to the project with the University of Zilina OPVaV-2009/2.2/04-SORO number (26220220101). Its name is Intelligent System for Nondestructive Technologies to evaluation of functional properties of parts of X-ray-diffractometry. The main objective of the project is to transform new nondestructive technology for knowledge transfer to industry for evaluation of functional parts in surface and subsurface layers of non-destructive techniques.

This paper is concerned with an experimental and numerical study of the fatigue behaviour of cylindrical 6063-T66 welded specimens subjected to biaxial loading. In-phase torsion-bending fatigue tests under constant amplitude loading were performed in a standard electromechanical machine with a suitable gripping system. The experimental part was focused on the modeling of combined biaxial loading and determining the number of cycles to fracture in the region of low-cycle fatigue. In-phase loading can be treated fairly well using the conventional hypotheses (von Mises or Tresca) on basis of the nominal, structural or local strains or stresses. Based on the experimental results the fatigue design curves are compared to the fatigue data from base metal and weldments.

Q245 steel was once widely used in the pressure vessel industry.At present, the high temperature fatigue performance of Q245 steel was tested and analyzed. According to the relevant standards, the pre-crack specimens were tested at 25℃and400℃respectively. The a-N curves, the da / dN  K curves and the Paris formula of Q245 steelat both room temperature(25℃) and high temperature(400℃) were obtained. Finally,the high temperature fatigue fracture analysis was done.The fatigue crack growth occurredalong the grain at high temperature. A large number of acicular oxideappearin the fracture surface and the fatigue striations could notbe observed at high temperature.

Many materials of general interest, which they are frequently employed in common life, industry, biotechnology, tissue engineering studies, medicine, have many excellent properties, but their inert nature may limit their wider usage in some cases. Many modification techniques have been therefore developed to improve surface properties of variable substrates for other applications. For a long time we study surface properties of a wide range of substrates (polymers, glass, silicate powders, etc.). Surfaces of studied materials are firstly activated by chemical or physical ways and than variable chemical compounds (e.g. nanoparticles, nanostructures or nanolyers) are grafted or deposited on. Surface properties are characterized before and after individual activation or modification steps by many techniques (microscopies, spectroscopies, goniometry, electrokinetic analyses, X-ray diffraction, etc.). Some of tested samples are also tested for antimicrobial activities and/or for cell adhesion and proliferation for their potential usage in tissue engineering. This paper presents a survey of techniques for preparation of nano-structured materials for usage in electronic, optics or medicine and selected results.

The research is focused on an analysis of bonds adhesive bonded with structural two-component epoxy adhesives by means of an electron microscopy. The paper deals with an evaluation of basic factors influencing an adhesive bond creation with an emphasis on a resultant adhesive bond quality. The adhesive bond quality was reviewed on the basis of an assessment of reached adhesive bond strength, a fracture surface and by a research on adhesive bonds cuts by means of the optical analysis (SEM). Evaluated criteria of the adhesive bond creation were: the adhesive bonded surface treatment, the time of an adhesive workability and the loading value at the fixation of adhesive parts. The results of SEM analysis proved an occurrence of impurities in the adhesive bond at omitting the chemical cleaning of the adhesive bond which get into the adhesive layer. The adhesive bond strength fall was more than 70 %. The strength and the quality of the adhesive bond depend on the adhesive bonded surface treatment, the adhesive workability time and the loading value of the adhesive bond at its creation. Above mentioned conclusions were proved by the mechanical tests and SEM analysis.

An intermodal transport is nowadays an inseperable part of a transport system. Designs of longer wagons are the result of efforts to achieve universality, transport capacity increase, reducing of noise and maintenance needs. In this paper are presented results of selected parametres of a long goods wagon driving on a test track. The long goods wagon and test rings models have been created by using the ADAMS/Rail software. The analysed wagon has been equipped by the Y25 bogie. Simulations of the long goods wagon running have been performed on the model of railway test rings - VÚŽ Velim, Cerhenice. For the dynamic analysis of the long goods wagon have been selected two sections of the railway test rings. For the ride properties wagon assessemnt have been selected output signals of vertical forces Q, guiding forces Y and the Y/Q ratio. There have been detected, values of assessed parametes have not been exceeded the limited values and therefore wagon runnings have been safety.

Currently, traditional materials are very often replaced by composite materials in many industrial areas. The advantages of these materials consist mainly in their lightweight, high strength and flexibility, corrosion resistance and a long lifespan. The use of composites reaches its large development in the field of aerospace. This article discusses quality of the manufacturing process technology of a specially shaped composite frame in 3D space. The used technology is based on a winding of carbon, glass, organic filament rovings on a polyurethane core. Polyurethane core which is a geometry of frame with and without a circular cross section. Quality production of said type of composite frame depends primarily on the correct winding of fibers on a polyurethane core. It is especially needed to ensure the correct angles of the fibers winding on the polyurethane core and the homogeneity of individual winding layers. The quality of fibers winding also depends on the material properties of polyurethane core and fibers. The article describes mathematical model for use an industrial robot in filament winding and how to calculate the trajectory of the robot. When winding fibers on the polyurethane core which is fastened to the robot-end-effector so that during the winding process goes through a fibre-processing head on the basis of the suitably determined robot-end-effector trajectory. We use for description numerical model and matrix calculus to enumerate the trajectory of the robot-end-effector to determine the desired passage of the frame through the fibre-processing head. The calculation of the trajectory was programmed in the Delphi development environment. Equations and relations of the numerical model are important for use a real solving of the passage of a polyurethane core through fibre-processing head.

The aim of this article is proposition of new methodology of experimental analysis of long-term monitoring of sandwich composite structures. The sandwich composite structures are, due to its properties like stiffness, high impact strength, corrosion resistance, low thermal conductivity and low acoustic conductivity and, commonly used in civil engineering in recent years. This type of structure is composed of two main parts (face sheet and core) having different material and mechanical properties. Sudden change of these properties causes interlaminar stress in structure. A good knowledge about behaviour of sandwich composite structure is important for efficient manufacture techniques, long-term prediction of structure behaviour and for economics. The experimental part has been focused on obtaining the experimental results of deformation between layers of sandwich composite structure during long-term monitoring. The long-gauge optical fibres SOFO® SMARTape Compact have been used for long-term monitoring of sandwich composite structures. Long-gauge optical fibres were placed between the foam core and an outer layer of the composite structure during manufacturing. Test specimens were loaded in three-point bending test.

The paper deals with the methodology of heat transfer coefficient measuring while using squeeze casting process. The casting with crystallization under pressure was used, specifically direct squeeze casting method. The pressure applied to the melt causes a significant increase (up to ten times) of the coefficient of heat transfer between the casting and the mold. The paper deals also with obtained results of the measured temperatures in the mold and the casting. The goal was to affect crystallization by pressure with value 100 MPa. On the basis of the measured variables were calculated values of heat flux between casting/mold, and consequently also the values of heat transfer coefficient.

The article deals with the use of Siemens digital factory concept for production capacity planning. In the increasing competitive environment of globalized world economy, pressure to grow effciency of production pro-cesses and systems greatly increases. In addition the increasing cmplexity of product requires appropriate as well as-sembly and logistic processes as production process planning and control. These requirements in the production process planning and cotrol may be due to its complexity filled only with appropriate instruments provided by comprehesive concept of the digital factory, which allow effective use of information on production, promote collaboration between departments and provide relevant data to anyone who needs it. This paper describes implementation of digital factory simulation tools for the production process planning and control at our industrial partner. This approach to production capacity planning using the digital factory concept is unique in the Czech Republic.

Within the research, an attempt was made to determine influence of preliminary wetting of high-silica based eco-friendly moulding sands containing sodium water-glass on effectiveness of their hardening by traditional drying. Effectiveness of adding water to the base during stirring was evaluated by comparing mechanical and technological parameters after traditional drying at 100 °C. Medium high-silica sand and two grades of hydrated sodium silicate 149 and 150 were used in the examinations. It was found that modification of preparation procedure by adding a proper quantity of water to high-silica base before adding binder (1.5 wt%) favourably affects mechanical and technological parameters of hardened sandmix. Results of the measurements are correlated with SEM observations of links between base grains. On the grounds of complex evaluation of moulding sands hardened by traditional drying, a positive effect of water addition was found, especially in the sandmixes containing binder with higher viscosity, i.e. grade 149. Optimum quantity of water addition should be determined for each specific grade of binder.

In this article is described, how can ultrasonic method Phased Array be used for inspection of weld joints made by electrofusion welding on plastic pipelines. For purpose of testing and to develop a proper setup, several artificially made defects were created in the weld area to verify, if this method can be successfully used for this application, since standards for testing of plastic pipelines have no specific regulation for this method. Therefore we are trying to propagate this method for gas and water transport industry, because it can severely reduce risks of accidents caused by unidentified defects, which can occur in welded joints.

This work deals with fatigue testing of the EN S355 structural steel welded joint. The weld was manufactured by the MIG welding technology and as the filler material was used the G3Si1 wire. The fatigue tests were carried out in the rotating bending mode on the specimens manufactured from the welded joint of the S355 steel. The main aim was to evaluate the fatigue endurance of the weld material and for this reason were used machined axis symmetrical specimens to remove the notch effect of the weld shape. In order to increase the fatigue endurance of the weld, the Nd-YAG laser was used for laser shock peening (LSP) of specimens surfaces, which lead to removing of the weld defects but in overall caused that LSP has behaved as the notch and lead to decreasing of the fatigue endurance. Obtained results of fatigue tests are compared, discussed and supported by correlation with results of additional experiments, e.g. identification of incurred structures after the laser shock peening by the metallographic observations and micro-hardness tests.

The paper presents the research results of the various coatings deposited using the cathodic arc evaporation Physical Vapour Deposition (PVD) method at 300°C, suitable for application on temperature-sensitive steels and alloys. Three main groups of coatings are deposited, denoted as E1, E2 and E3. The deposited bi-layer numbers for E2, E3 and E4 are 103, 207 and 107, respectively. Each group consists of two subgroups, S1 and S2, TiN/AlTiN and AlTiN/TiN nanomultilayer (NML) coatings, respectively. The coating deposition time for E1 and E2 is 60 min, and the carousel rotation speed is 35s and 17.5s, respectively. The coating thicknesses for these two coatings groups are 2.4 μm and 2.3 μm, and the calculated bi-layers thicknesses are 23.3 nm and 11.6 nm, respectively. TiN/AlTiN and AlTiN/TiN as NML or superlattice coatings are deposited onto high-speed steel substrates using pure titanium and aluminium-titanium (70/30 at. %) cathodes. Tribological testing is conducted using an Al2O3 ball and a ball made from steel ISO 683/13, and the applied load and path length at the used speed of 60 RPM are 10N and 25m, respectively. Measurements are performed at room temperature and a humidity of 44 ± 2%.

Merchant's model of chips formation considers an "ideal" (sharp) cutting edge. However, nowadays many manufacturers of cutting tools modify the tool geometry with the goal to increase the tool life and to improve the surface quality. The processes, at which the modified tools are used, go along with chip formation and physical phenomena that differ from Merchant's model.
The article deals with the simulation of chip formation at various ratios of rounded cutting edge and cutting thickness. Aim of the research has been focused on the interpretation of new knowledge from the cutting theory. Authors have tried to understand the theory of cutting process by means of simulation and provide the recommendations for practical usage. They explain the differences between the Merchant's model with a sharp edge and a model with a rounded cutting edge. The contribution describes changes and manifestations of physical phenomena result from given conditions. There were also simulated dependencies of the tool load on the radius of cutting edge in the article. Achieved results will enable not only better integration of cutting tools into the manufacturing, but they also allow to increase the machining efficiency.

This article is focused on the processing of steel materials by thermal cutting technologies - laser cutting. It analyzes the impact of technological parameters - cutting speed effect on the cutting surface quality. The goal is to define the parameters ensuring proper amount of heat absorbed into the material that does not affect the cutting surface to avoid difficultiesduring further processing - such as drilling, thread cutting etc.To determinethe effect of cutting speed on the quality of the cutting surface, it was necessary to measure an internal stress and a hardness of HVM. Internal stresses in the experimental part of the article was measured by the X-ray diffraction and the resulting values are shown in the graphs.In the article are also shown microstructures of selected samples after the laser cutting under the different cutting parameters.

The present paper deals with the metrology, especially with the legal metrology that is responsible for assuring the uniformity and correctness of measurements. In addition to the definition and explanation of the basic terms and principles applied in the metrology, the paper presents especially the results of the scientific and research work in the cross-disciplinary fields of the legal metrology in Slovakia, namely in design and realization of a new measuring system for the verification of the radar level gauges.

To improve mechanical properties of adhesive bonds and to reduce an amount of an adhesive spherical particles or fibres are used. Glass and carbon fibres are mostly used types of fibres, however, they are not environmental friendly. So biodegradable materials, namely jute, cotton and linen were used for experiments. The aim of the experiment is to clarify the fatigue behaviour of structural two-component epoxy adhesive applied to a constructional steel S235J0. The fabrics were composed of jute, cotton and linen in a plain weave and the weights in grams 140g/m2 for cotton, 261g/m2 for linen and 305g/m2 for jute were used. The specimens for quasi-static and lap shear strength tests were made in accordance with EN 1465:2009. It is obvious from the experiment results that it came to the improvement of the quasi-static loading at adhesive bonds reinforced with linen, the increase of static strength was about 28 % compared with bonds without fabric layer.