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This paper presents the nonlinear analysis of the reinforced concrete buildings of nuclear power plant under the aircraft attack. The response from the nonlinear analysis was considered taken the deterministic calculation procedures. The dynamic load is defined in time on base of the airplane impact simulations considering the real stiffness, masses, direc-tion and velocity of the flight. The dynamic response is calculated in the system ANSYS using the transient nonlinear analysis solution method. The damage of the concrete wall is evaluated in accordance with the standard NDRC consid-ering the spalling, scabbing and perforation effects. The simple and detailed calculations of the wall damage are compared.

Sound reflection of materials is influenced by many factors, e.g. by material type, density, thickness, porosity, angle of sound incidence, surface shape and excitation frequency of acoustic wave. The aim of the paper is to investigate the surface shape effect of expanded polyvinylchloride material on sound reflection. For this reason polyvinylchloride samples of different surface shapes and perforations were produced on universal and CNC machine tool. The material ability to reflect sound of the investigated polyvinylchloride samples was experimentally measured by means of the transfer function method on Kundt's impedance tube. The material samples were subsequently compared in terms of their sound reflection. It was verified that the highest sound reflection was obtained in case of the smooth surface polyvinylchloride sample.

The article deals with the basic steps of injection mould design. The goal of the research was the proposition of the mould form so to be achieved the minimum waste and the shortest time of both mould filling and product cooling. Studied mould component is intended to serve as a stopper in the automotive spotlight. The simulations were realized for three designed types of running system and for four versions of cooling system. Due to the design optimization, the pressures, originated inside the cooling system and inside the mould cavity during the injection moulding process, were also investigated. 3D model of the mould was created in Autodesk Inventor Professional software and then solidification of material was simulated in Autodesk Moldflow. On the basis of the best solution, real form was manufactured and placed into injection moulding machine Arburg Allrounder 320 C.

Nowadays, constant pressure on enviromental aspects in the foundry industry is calling for an improvement in casting production. The almost not used inorganic binders are coming back to the fore. Into this group, among others, belong binders based on alcali silicate solutions, known as water glass. The new hot-curing binder systems were introduced by different binder manufacturers. In order to compensate dissadvantages of alkalic silicate binder, the systems and processes are working with additives and adjuvants which are contained in a binder itself or added in liquid or powder form to the sand mixture. This paper presents the ASK Inotec process and impact of silica sand granulometry on achieved core mixture strength, which is important from a core production and also from a decoring ability point of view. Experiment was performed in laboratory terms using standard equipment and conditions.

In the paper, results of a research on influence of piston stroke rate on structures of AlSi9Cu3(Fe) (EN AB-46000 group) castings manufactured at constant intensification pressure of 290 bar are presented. Relation between piston speed (0.3-2.3 m/s) and casting structure was evaluated after a series of trial high-pressure castings. The examinations were carried-out on properly prepared samples taken from the castings in places with the largest cross-section area. The effect of pouring rate was evaluated on the grounds of metallographic observations on a light microscope and a scanning electron microscope. It was found that larger grains of the very hard phase solidify at low piston speed between 0.3 and 0.75 m/s. Higher piston speed results in finer casting structure and in refinement of particles of intermetallic Fe-Mn phase, which is beneficial for usable properties of the castings.

The goal of every company is to be a successful producer. There are no easy ways because there are a lot of factors that have varying impacts on the final profit. One of the most significant factors is production time. If the processing phases of the production of polymer products are compared, cooling is clearly the most time-consuming. The reason lies in the poor thermal conductivity of polymers. Therefore is very important looking for the optimally way of cooling. One of the very interesting improvements of current production process is application of progressive internal cooling systems which using cold medium, such as deep-cooled air, the injection of a mixture of water droplets with pressurized air or the injection of liquefied inert gas (CO2, N2). When these internal cooling techniques are compared, it is clear that the highest production increasing is achieved by the technology injection liquefied gas. Although this technology has been known for some time, it has not been widely used until now. The reason for this could be some production restrictions and process disadvantages. The main goal of this paper is therefore focused on find out these limitations.

Titanium dioxide in its anatase allotropic modification is well known for its photovoltaic and photocatalytic activity. Through a modification of Nanospider™ device it was achieved a continuous production of nanocrystaline anatase nanofibers. These inorganic fibres have a huge specific surface area due to their fine diameter and structure and thus offer a promising potential in many applications. In this article it is described the device allowing continuous production of inorganic TiO2 nanofibers by the use of electrospinning process and optimization of following calcination process leading to obtaining of almost pure nanocrystaline anatase structure.

The present paper expands the knowledge in the field of welding of age hardening aluminium alloys using MIG method. Aluminium alloy AW 6082 (AlSi1MgMn) according to the specification standard CSN 42 4400 was used for the experiment. This type of alloy is used in industrial practice e.g. for medium stressed parts in railway and motor vehicles and in water, oil or petrol pipes. For the purpose of assessing the impact of multiple cycles on the properties in the heat affected zone the weld was designed as a multi-layer weld. The objective of this paper is not only the impact assessment of the degradation of the mechanical properties, but also the possibility of recovery of these properties by heat treatment. During the experiment, the effect of temperature holding time by solution annealing and artificial hardening on the mechanical properties of the base material, HAZ and weld was studied. The effect of heat treatment was evaluated by Vickers hardness test.

Crystal segregation is taken as chemical heterogeneity under the micro-scale and it develops during the crystallization process. Alloy crystallization does not take place under a particular temperature, as it happens in the case of pure metals, but it runs under a certain temperature interval. When cooling the melt, various places start development among dendritic cells which differ in their chemical composition. Crystal segregation can be generally defined as chemical heterogeneity developing during the alloy crystallization process, and it can be either en-riched or in contrast depleted with alloying elements and impurities, which are unevenly segregating over the en-tire dendritic surface. In the central part of the dendritic cells there is an alloy, which is depleted with alloying elements, while the edge areas of dendritic cells and interdendrite space present higher concentration of alloying elements. This concentration shows a hyperbolic development; when the central part of dendritic cells area has the lowest alloying elements concentration, while the edge part of a dendritic tree and the interdendrite space show the maximum concentration. The distance between two main axes of dendritic cells is affected by the temperature interval running between the liquid and solid phase of the chosen alloy, as well as by melt cooling rate and temperature gradient during the solidification phase. The shorter distance between the axes of dendritic cells appears under faster cooling, which allows very fast heat dissipation and creates very fine structure of the resulting alloy. The longer distance between the main axes of dendritic cells stimulates greater segregation appearing under slow melt cooling.
Crystal segregation formation of aluminum alloys enriched with alloying elements and impurities cannot be prevented, only its extension can be regulated and it can be suppressed with the correct choice of heat treatment parameters. To suppress the crystal segregation the casts should undergo heat treatment which is called homogenization annealing.

Ti-Al-Si alloys are very prospective materials for many applications, particularly for automotive and aerospace industry, due to their low density, excellent resistivity to oxidation and heat stability. The main problem is high brittleness at room temperature and high mechanical characteristics persisting only up to 800 °C, which is limiting in some applications. Ti-Al-Si alloys were prepared by powder metallurgy using Self-propagating High-temperature Synthesis (SHS), which is considered as a first step in production consisting of SHS, milling and consolidation by Spark Plasma Sintering. In this experiment the observed subject was the microstructure and phase composition of Ti-Al-Si alloys in order to find optimum alloy composition for desired technology. Based on the results of this work, TiAl15Si15 alloy can be recommended due to fine microstructure composed of titanium silicide (Ti5Si3) particles in the matrix of titanium aluminide (TiAl). Concerning the production by SHS, the highest achievable heating rate can be recommended.

An article deals with a definition, concept, development, calculation and construction of a prototype solution of a mechanical regulation of a turbine ventilator using a half-flap eliminating an amount of ventilated air. The whole mechanical regulation solution lies in a central shaft. When a rotation nozzle is spun to high revolutions, a flap closes gradually and eliminates air flowing. This prototype of the mechanical regulation may be used for classic concepts of turbine ventilators, where the rotation nozzle stays in one position and only rotates around its own axis.
The article describes individual development stages from the concept up to construction, including a final visualization of the prototype solution of the mechanical regulation of the turbine ventilator using the half-flap. The mentioned innovative solution of the mechanical regulation is very up-to-date thanks to its simplicity and nonservice operation. It is just the matter of time when one of the producers would be interested in the turbine ventilator solution and it would be introduced into a market space.

This work deals with the problematics of 3D printing. Additive manufacturing (AM) covers a lot of principles of producing products and prototypes, for example, Direct Metal Laser Sintering (DMLS). This principle is based on sintering metal powder in thin layers, layer by layer. This theme is very extensive and a very popular research area. The paper is focused on printing thin walls. The material for printing was Maraging Steel MS1. This material achieves great mechanical properties like as high strength and high hardness. The tensile strength can be up to 2000 MPa after age hardening. The printer used was an EOS M290. The effects of different part position on safety of printing are compared. Also, the effect of support structures on accuracy was investigated. The main part of the paper is focused on an experiment where thin walls are printed and subsequently evaluated. The influences and limitations were investigated. The measurements were carried out on a Blickle Multicheck PC500 microscope.

A chemical cleaning of an adhesive bonded surface is a significant technological factor at a creation of an adhesive bond. Owing to the fact that producers do not provide information about releasing of harmful substances into the atmosphere mass values of a flow of pollutants were experimentally tested in various chemical environments serving for an adhesive bonded surface treatment. A piece of knowledge of the mass flow of the pollutants which are released into the space is a possible solution which is dealt with in this paper. There is a difference in the individual chemical treatments influence on the adhesive bond strength. The scanning electron microscopy was used for the evaluation of the influence of the chemical treatment of the adhesive bonded material on the adhesive bond quality. The adhesive bond strength was determined depending on the chemical treatment of the surface on the base of mechanical tests. The adhesive bonded surface treatment did not change the fracture surface. The optimum values of the adhesive bond strength and the lowest values of the evaporation in the environment at the same time were reached at perchlorethylene and toluene.

Grinding operations are sometimes replaced with hard turning or milling cycles. Mechanism of chip separation during grinding and the corresponding surface integrity remarkably differs from hard turning or milling. For this reason, this paper deals with application of Barkhausen noise for evaluation of surface anisotropy after hard milling. Experiments were carried out on bearing steel 100CrMn6 hardened on 45, 55, 62 HRC and one series without heat treatment. The analysis contains comparison of RMS values for the different hardness and tool wear after hard milling and also discusses the specific mechanism of BW motion in the case of cyclic magnetization.

This article deals with the analysis of the chemical pre-treatment influence on the corrosion resistance of the low carbon unalloyed steel material after cold forming. These are the pre-treatments nanotechnology based. The layer is created by sol-gel technology. Except two used types of nano chemical pre-treatments is also used classical ferric phosphate. The six variants of chemical pre-treatments were prepared and these variants were then compared in terms of corrosion resistance and the way of exclusion and surface morphology using SEM and EDS analysis. The experimental samples were prepared for each variant. They were observed macroscopically and using SEM before corrosion load. These analysis shows the differences between each variant. Using SEM and EDS analysis was searched the typical elements for each variant and was observed the excluded layer and potential defects. The experimental samples were placed in the corrosion chamber and loaded according to the standard CSN EN ISO 9227 after this analyses. The surface of the experimental samples were without any other protection thus there was observed changes on the surface of the samples after one hour. The corrosion loading was finished after 24 hours. Experimental samples were evaluated macroscopically and were compared. The result of the experiment is the best variant of chemical pre-treatment in terms of corrosion protection of steel substrate concluded after all analyses and observations.

This study discusses the impact of heat treatment conditions on the final properties of quenched and low-tempered bearing components in terms of microstructure, hardness and impact strength. Technological process of heat treatment must be done rationally and in addition to the required hardness must also ensure the dimensional precision of bearings components. Different austenitization conditions have a great influence on the phenomena which takes place in the material during the austenitizing. Heat treatment of rolling bearing components is an indispensable part of their production and it is also an unavoidable item of the price calculation of bearings. The aim of a competitive struggle for the rolling bearings market is an offer of the best quality bearings (dimensional accuracy, stability and durability) at a reasonable price.

This essay aims to describe technology and mold design for production of hollow composite parts like carbon rims or sport rackets. Tested materials correspond to those used for composites in sport applications. Production technology called inflatable bladder molding (IBM) is describe with respect to used material, molds and process parameters. Furthermore, prototype mold for verification of flexible bladder, inner pressure and curing conditions is constructed and tested. Construction design of manufacturing mold together with description of technological steps is proposed.

At design of cutting tools the positioning of cutting edges and geometry of cutting inserts are becoming increasingly diversified with the development of cutting procedures. As a result, the generated tool marks on cut surfaces also can take many forms. Roughness values in face milling can change both in planes parallel with the feed direction and in planes at angle to it, therefore it is particularly important to be able to plan the roughness characteristics of surfaces. A new method is introduced in the paper for planning the roughness characteristics of cut surfaces that can be used to determine theoretical values of roughness characteristics of surfaces generated by tools having defined edge geometry. It is based on CAD modelling of the theoretical cut surface; practically any complex tool geometry can be modelled and 3D roughness parameters determined. In application of rotating tools a variety of tool designs and setting accuracy were taken into consideration during the determination of theoretical values for the simultaneous cutting of more than one edge. An example is shown for two different insert geometries.

Composite materials synergistically combine the properties of their sub-phases. Among the most widespread group of composite materials include fiber reinforced composites - usually with a polymer matrix. Mechanical properties of fiber composites are used in a variety of industries. The fibers can be represented by synthetic fibers or natural ones. Advantage of natural fibers is that it is a renewable resource, they are inexpensive, have adequate mechanical properties, which, however, due to the biological material may vary substantially. Described contribution deals with the experimental description of the tensile strength of two epoxy resins filled with short sisal fibers - random orientation of the fibers with different length, i.e. 2 mm, 4 mm and 6 mm. This paper compares the composite systems prepared from epoxy resins with different viscosity (resins Glue Epox Rapid, Glue Epox Rapid F) by casting. The presence of short fibers of sisal without controlled interlayer statistically unchanged tensile strength in many cases, and also increased the modul of elasticity in all cases.

Simulation of grinding is a topic of great interest due to the wide application of the process in contemporary industry. Up to date, several modelling methods have been utilized in order to accurately describe the complex phenomena taking place during grinding, the most common being the finite element method and artificial intelligence techniques, e.g. soft computing methods. The present paper proposes a new hybrid model for precision grinding, more specifically the combination of finite elements with neural networks. The model possesses the advantages of both the aforementioned methods, for the prediction of several grinding features that define the outcome of the process and the quality of the final product.

Final properties of castings made of aluminium alloys strongly depend on amount of impurities. Production of high quality parts thus requires strict control of impurity level or elimination of detrimental effects caused by presence of impurities. Such requirements are even more important in case of castings made of recycled materials. In Al-Si based alloys is very important awareness of the problems with the presence of iron as an impurity. Negative iron effect is expressive even in low amounts, and with higher level becomes more harmful. Elimination of its effects can be performed by several techniques, from which no one have general implementation. One of the possible ways is addition of so called iron correctors to the alloys. Influence of vanadium as iron corrector is still not precisely examined. In this article, influence of vanadium to AlSi10MgMn alloy with 1.0 wt. % of iron is analysed by tensile and hardness testing together with microstructural evaluation.

A soil processing belongs among basic steps in an area of a crop farming. The research was focused on increasing a service life of ploughshares by an overlaying technology. The research within field conditions was focused on innovations of ploughshares in the area of a conventional processing of the soil by means of the overlaying technology. A new functional profile was created by means of overlaying electrodes on the conventional tool in order to respect drainage of the processed soil, i.e. oblique overlays. The overlaying material was put in the most stressed places of the ploughshare, i.e. parallel with a face and an edge and these both in a front as well as in a back part. New functional surface was distinguished for a reinforcement of a top of the ploughshare edge and the back part of the ploughshare. Overlaying material was of carbide type OK Tubrodur 15.82. Within the tools service life testing under the field conditions the change of the tools shape and their mass loss were investigated. Statistical methods were used for evaluating of the experiments.

The article deals with the evaluation of the roughness of the machined surface, steel ISO C45 and ISO 11CrMo9-10 after machining at interrupted cutting conditions. A regular interrupted cut and irregular interrupted cut can have significant effect on the resulting surface of components. Parameters of roughness were measured on the slats, which was machined with using the interrupted cutting simulator. The slats were gradually machined - 4, 3, 2 and 1 slat for getting irregular interrupted cut. Selected parameters of roughness which were tested; Ra - an average arithmetic deviation, Rq - an average quadratic deviation and Rz - the maximum height of the roughness profile. Experiment took place in cooperation with Faculty of Mechanical Engineering of VSB - TU Ostrava and Faculty of Mechanical Engineering of ZU Zilina - machining in the laboratories of ZU Zilina, Slovak Republic.

Standardization is the basis for improvement in the company. This allows for repeatability performance of activities and thus the stability of the process. This chapter presents the standardization as part of Toyota's production system. Standardization is also one of the elements examined using the method BOST, because it was used for hot dip galvanizing process improvement. The research was carried out in one of the national companies producing steel products and providing services in the field of modern anti-corrosion protection, in particular hot-dip galvanizing.

In the report the results of bonded joints laboratory tests are published. The determination of the tensile lap-shear strength of rigid-to-rigid bonded assemblies according to the standard CSN EN 1465 (66 8510) was the aim of the carried out tests. The samples were made from steel sheets. For bonding of test samples four different types of adhesives were used (two super glue adhesives, one epoxy adhesive and one contact adhesive). Ahead of bonding the surfaces of all samples were blasted using corundum grit and degreased. For degreasing four various types of five different degreasers were used, namely perchlorethylene, acetone, methanol, technical gasoline and toluene. Then the samples were dried using warm air. For comparison the blasted samples without degreasing were bonded, too. At the tested samples bonding the consumption of adhesive was determined. From the adhesive consumption for one bonded joint and from the adhesive price the costs of one sample bonding were calculated. After curing the bonded assemblies were loaded using the universal test machine LabTest 5.50 ST up to their rupture. The rupture force was written down. From the values of the rupture force and the bonded surface size the bonded joint strength was calculated. By the carried out tests evaluation the influence of different degreaser types was determined. Also for all used adhesives the price of one bonded joint was calculated.

Metallic biomaterials are currently produced mainly by conventional metallurgical processes, i.e. the melting and casting used e.g. in production of cobalt alloy implants, or forming processes as cold or hot working (rolling or forging of stainless steel for surgical applications). Such processes including melting are used also in production of "smart" biomaterials - NiTi shape memory alloys. The mechanical properties are strongly dependent on the grain size. Therefore, the techniques to obtain finer structure are very desirable to enhance the mechanical properties of the biomaterials and thus to increase lifetime of the implant. This paper is devoted to the description of the possibilites of powder metallurgy not only for the structure refinement, but also for the ptoduction of clean biomedical alloys as well as the porous bioamterials. The use of powder metallurgy is described for Co-Cr-Mo surgical alloy, Ni-Ti shape memory alloy and Ti-based porous biomaterial. In addtion to known methods, new powder metallurgy processes and materials developed by the authors are presented.

The aim of this paper is to compare the mechanical and tribological properties of TiCN and CrCN coatings. These coatings are widely used in industrial applications to improve both friction and wear. They are deposited at the same deposition parameters using an industrial Physical Vapour Deposition (PVD) system. Estimation of the tribology properties is made in a "ball-on-disc" mode, and the wear and wear rates of the coatings and counter-bodies are compared. The test study is conducted using a ball made from Al2O3 with a diameter of 6.350 mm and a load of 10 N, at room temperature and a humidity of 44 ± 2 %. The mechanical properties are estimated by nanoindentation, a scanning electron microscope and a mechanical profilometer, and the hardness, elastic module, chemical composition, and surface coating morphology are estimated. The scratch test is performed on the coatings using a CETR UMI Multi-Specimen Test System scratch tester device with a progressive load from 2 to 100 N and speed of 10 mm/min, according to the ISO EN 1071-3:2005 standard.

This article offers a novel method of gold nanoparticles preparation which increases their obsevation feasibility. Gold nanoparticles were prepared by sputtering of 6 nm of gold on surface of NaCl crystals and consequent annealing. Gold nanoparticles were separated from the substrate mechanically in the ultrasonic bath. The preparation of gold nanoparticles on NaCl substate is extremely versatile. It enables to descibe size and shape of the individual nanoparticles much better than usually used SEM and AFM techniques, it enables to see the lattice arrangements and also to do more precise chemical analysis without the influence of the substrate. It is applicable for characterization of temperature-, time-, chemical composition- and atmosphere influence on morphology of gold nanoparticles. The nanoparticles were observed by HRTEM. In our case, the influence of carbon addition on morphology of gold nanoparticles was studied by sputtering one or two carbon interlayes in the gold layer. It was found out that one carbon interlayer slightly descrease nanoparticle size. On the other hand, two carbon interlayers lead to formation of irregular large shapes of the gold particles.

It is well known that the susceptibility of steels to hydrogen embrittlement is markedly dependent on hydrogenation conditions of samples. In this contribution are presented key results of relatively extensive studies oriented to examination of the effect of electrolytic hydrogen charging conditions (charging time and current density) on the hydrogen embrittlement of steels evaluated by the slow three point bend tests, micro- and macro-hardness tests. Various kinds of industrially produced hot rolled steel strips were tested (structural steel, dual phase and HSLA steels). The major aim of this study was to determine the hydrogenation conditions that do not result in the formation of defects such as microcrack or voids (in terms of absence of defects found by using optical microscopy) during hydrogen charging process.

Titanium-aluminium base nanomultilayer (NML) coatings are deposited by cathodic arc evaporation using pure titanium and aluminium with eighteen percent silicon cathodes. Each multilayer Ti-Al-Si-N structure consists of 49 bi-layers with different thickness. The external deposited layer is with five times longer growing period. The coatings are deposited at the pressure of 2 Pa and the substrate temperature of 400 °C. Polished steel discs (Ø 20 mm × 5 mm thick) are used as the substrate material.
This article presents an investigation of the surface morphology and mechanical properties of the coatings, particularly the adhesion and nanohardness. The AFM analysis indicates that the coatings are dense, with an average surface roughness in the range of 33 / 58 nm. The coating with the smaller value of average surface roughness exhibited a maximum hardness of 43 GPa. High calculated value of plasticity index (H/E) is 0.104. The scratch test results revealed that all the investigated coatings have very good adhesion in the normal loading interval from 1 N to 40 N.