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The ultrasonic/ceramic membrane combined process was employed to have a better effect of the filtrated water quality. We set the ultrasonic frequency at 20 kHz and the corresponding power at 2kW. Innovatively we probed into different range of molar weight of organic matters in the filtrated water, and results showed that the ultrasonic/ceramic membrane combined process could change the distribution of micromolecule organic matters. We found that with the increasing of turbidity of raw water, the membrane flux decreased rapidly but the quality of filtrated water changed little. Studies on different range of molar weight showed that for the organic matters whose molar weight were below 1kD, higher turbidity had an optimistic effect on removing them while for those whose molar weight were above 1kD, the effect was reverse.

A mechanical treatment of an adherent before an application of adhesives is one of key factors influencing resultant strength of an adhesive bond. A grit blasting belongs among one of the most often used methods of the surface treatment. A resultant structure of blasted adherent and also parameters of the surface roughness can be changed during the blasting by a suitable choice of many parameters among which a material and a size of abrasive particles, a distance of an air jet and a blasted material, a size of the jet, an air pressure and an angle of abrasive particles impact can be ranked. This experiment describes an injector system of grit blasting using basic abrasives - corundum and glass ballotini. During grit blasting of common steel adherent it came to the change of the impact angle of the abrasive particle in a range from 75° (a perpendicular angle) to 10°. Different impact angle led to different roughness parameters and to various structure of the adherent surface which was evaluated by an electron microscopy. Subsequently, it came to experimental description of the strength of adhesive bonds which were created by adherents whose surface was grit blasted under various impact angles of abrasive particles.

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.

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 describes experimental and numerical investigation of airflow inside the floor convector. Analysis was divided to two parts. First part was airflow visualization. This part was realized in two areas. At first the visualization was realized in the area between a fan outlet and a heat exchanger inlet using a continual laser and a video camera. Then the visualization was realized in the region above the heat exchanger outlet with a Particle image velocimetry. At last the flow behavior in domain between the fan outlet and the floor convector outlet was analyzed with a numerical simulation. Commercial software ANSYS Fluent in version 15.0 was used. Results from the numerical simulation and the experiments were compared and the flow behavior was examined.

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.

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.

The article deals with the results of the simulation analysis of a railway wagon bogie model. We analysed four freight wagon bogie variants for its dynamics properties research. The bogie models correspond in general to the Y25 bogie concept. The models were created in SIMPACK software enhanced by the RAIL module. From the research results depicted in the graphs we found out, that the newly designed bogie variant gives the best results when compared to the other analysed versions. The newly designed model consists of a standard Y25 bogie frame with two Lenoire friction dampers. This bogie is equipped with longitudinal linkages on both sides. These linkages are completed with a radial torsion binding, torsion rod, between side bogie parts. The contact of railway wheels and rails generates active forces affecting the surface contact, affecting the size of the normal and tangential stress, wear surfaces of the wheel/rail, or directly the size of the derailment.

Many solid materials are subjected to structural changes, e.g. phase transformations within temperature change. These phase transformations are usually accompanied by a significant change in particular volume. The change in volume of a solid material is measured by the corresponding change in length of a specimen of the material. The experimental method which is based on measurement of volume/ length change during linear heating or cooling is dilatometry. Dilatometry is characterised by the linear thermal expansion coefficient which can be described as the relative length-change divided by the corresponding temperature interval. The basis of the thermal expansion of crystalline material is related with the function between interatomic forces in crystal lattice. This paper investigates the effect of temperature on structural changes within austenitic stainless steel that underwent different heat treatment before the measurement.

A paper deals with technological applications of laser. It evaluates the influence of design and technological conditions on output parameters of cutting process and also presents relative laser machinability of polymeric and metallic materials; in addition, it shows possible evaluation of structural change of metals and it gives mathematical model for determination laser cutting quality functions based on results of the experimental research. The temperature distribution has been derived. Results of plastic materials and hard-to-machining metals machinability are shown. Finally, surface quality evaluation after exposure to concentrated light energy and quantification of material microhardness are described.

Composite materials, such as fibre reinforced plastics and sandwich panels, have considerable potential for use in the next generation of transport structures. They are lightweight, durable, and readily moulded to shape. However, there are also additional complexities associated with the use of composites, particularly in terms of design and manufacture. These complexities, together with issues of cost, are currently limiting their adoption by the transport sectors. The selection of the manufacturing process for a composite component will normally depend upon the nature of part and the required production volumes. We try to present vacuum assisted resin infusion process, suitable for low-medium production volumes (less than 500 parts per year). Vacuum infusion is well suited to large parts (greater than 1m) with intermediate fibre content (less than 35% by volume). As a reference product was selected overhead - side panel of train cabin designed like a sandwich construction with suitable foam or honeycomb core. Our experimental results described vacuum infusion process like actual variant to produce designed products to transport industry.

The main aim of this experimental paper is investigation, analyzing and realizing the experimental measurement of cutting temperature when external turning of rotational parts made from AlCu3MgMnPb aluminum alloy. In this experimental study a number of turning tests have been carried out by using a test lathe and a cutting temperature measuring device. This measurement have been successively investigated and experimentally verified with the special samples (in experimental measuring of the temperature during the turning process of samples and measured results designated with special thermal camcorder type FLIR used for special measurement of cutting temperature). The theoretical contribution of the realized experiment is the finding that the change of cutting speed, depth of cut, feed motion and cutting temperature increase with increasing of the chip emerging influence factors change over time. Practical benefit is recognition that the emerging shape of the chips in turning of aluminum alloy is a consequence of the deformation process, which depends on the measured sample from its crystal structure and the conditions under which the deformation process occurs mainly by the deformation, cutting speed and temperature.

The research into root causes of defects in cylinder head castings are described in the paper. Chemical composition of castings, evaluation of casting microstructure before and after the heat treatment and final inspection of casting quality from various points of view are parts of the research. The list of the most common defects in case of using five selected products is the result of the experiment. The objective of the research was to identify causes of defects in the process of cylinder head casting as well as to identify root causes of discrepancy using the quality management tool.

Approximately equiatomic alloy Ni-Ti is commercially most successful member of shape memory material group. This paper concludes basic knowledge about properties, ways of preparation and possible applications of this unique material in medicine, industry, construction or everyday life.

The paper analyses the possibilities of modification of cutting tool geometry in order to preserve a protective plastic zone of material at a cutting tool. Based on the results of model experiment as well as practical verification, a rapid increase in tool life has been achieved. The tool life is dependent on the size of the shortened rake face. Optimization of the tool face size enables to achieve multiplied tool life when comparing with a classical cutting tool. A uniqueness of this processes is the formation of the two chips, one of which is a created plastic layer along the edge of the cutting tool. The application of the tool is possible only with the plastic material cutting. Experimental tests were realized with usually used steels.

The contribution contains results of bonded joints strength tests. The tests were carried out according to the modified standard CSN EN 1465 (66 8510). For bonding the spruce three-ply wood of 4 mm thickness was used (according to CSN EN 636). The test samples of 100 x 25 mm size were cut out from a semi-product of 2440 x 1220 mm size in the direction of its longer side (angle 0°), in the oblique direction (angle 45°) and in the direction of its shorter side (crosswise - angle 90°). The bonding was carried out using eight different domestic as well as foreign adhesives according to the technology prescribed by the producer. All used adhesives were designated for wood bonding. At the bonding the consumption of the adhesive was determined. After curing the bonded assemblies were loaded using a universal tensile-strength testing machine up to the rupture. The rupture force and the rupture type were registered. Finally the technical-economical evaluation of the experiments was carried out.

The article presents the measurement results of the relaxation of long-term loaded compression springs manufactured out of non-alloy steel. The goal was to determine the differences between the interrupted and uninterrupted tests. During the relaxation test that lasted 5000 hr in a laboratory with a temperature of 22ºC, initial shear stress set at a value of 30% of the ultimate tensile strength of the material, decreased the strength of the springs with a wire diameter of 1 mm by 3.6%, springs with a wire diameter of 3.15 mm by 2.5%, and springs with a wire diameter of 5 mm by 1.3%. The difference in the results was found in tests 16 times and 4 times interrupted to measure the current relaxation. The results of intermittent tests cannot be considered as relaxation values for statically loaded springs. Conversely, when determining the maximum tension of quasi-statically loaded springs with respect to the relaxation, the uninterrupted relaxation tests cannot be used.

An application of an adhesive bonding technology is limited by cyclic loading of an adhesive bond. The aim of the experiment is to clarify a fatigue behaviour (low-cyclic tests of the fatigue) of four structural two-component epoxy adhesives applied to an alloy AlCu4Mg. The aim of the research was to evaluate a service life of the adhesive bond in terms of its fatigue stressing at the quasi static shear test. From that reason values of a passing loading for low-cyclic fatigue test were chosen for tested adhesives, i.e. 25 %, 50 % and 75 % from a reference value of a maximum force gained at the static test according to CSN EN 1465. The critical value at the low-cyclic fatigue test was determined from the experiment results for the adhesive bond as 75 %. Most of the adhesive bonds did not reach 100 cycles at this value.
It is obvious from the results that the considerable change of the adhesive bond strength did not occur after 100 cycles at the passing loading corresponding to 25 % and 50 % of the average maximum strength of the adhesive bond. The average fall of the resultant adhesive bond strength was in the interval 3 % to 11 %.

Nowadays, one of the motive trend in engineering industry is transportation and manipulating technology. The hydrostatic mechanisms belong to the most important components and are created by hydraulic engines, pumps, switchgears etc. Inseparable part of hydraulic engine is a servo-valve which coordinates the fluid flow by a microscopic movement of piston. The servo-valve is a casting, usually made of ductile cast-iron that is necessary to machine. The functionality of hydrostatic circuits is influenced significantly by the precise movement of pistons.Therefore it is necessary to provide the dimension accuracy, machining quality and also the geometric shape of holes. This article describes the issue of holes reaming in hydrostatic components with a use of reamers made of sintered carbide and cermet.

The most widely used technologies of founding Al-Si cast alloys are gravitation and semi-centrifugal casting, casting under pressure and so on. The contribution deals with influence of different casting method on changes of Fe intermetallic phases. Casting into metallic mould and sand mould were used for experimental work for comparison Fe-rich formation. Fe is a common impurity that leads to the formation of complex Fe-rich intermetallic phases. The dominant phase is plate-shaped Al5FeSi. These phases are unwaited, because reduce properties of aluminium casting. The experimental materials have most common addition Mn. The addition of Mn may reduce Al5FeSi phase and promote formation Fe-rich phases Al15(FeMn)3Si2 in "skeleton like" or "Chinese script" form. This knowledge was confirmed. The present study is a part of larger research project.

Aluminium bronzes can find use in many engineering applications thanks to their excellent properties, predominantly high corrosion resistance, good ultimate tensile strength, fatigue strength and creep strength. Yet, their mechanical properties can still be improved, most importantly by appropriate heat treatment. The type of heat treatment is typically chosen with regard to the desired properties of the product and its service conditions. This paper attempts to summarise the microstructural changes which take place in aluminium bronzes during heat treatment. Another objective of this study was to map the potential of a certain type of aluminium bronzes for undergoing martensitic transformation. The methods, which were chosen for assessing the results of heat treatment with regard to their availability, included measurement of hardness and observation of microstructure using light and scanning electron microscopy, Additional tools for evaluation of microstructure comprised measurement of microhardness and chemical analysis by EDS.

Direct Metal Laser Sintering enables production of fully dense metal parts with comparable or higher tensile properties as compared to the conventionally produced parts. However, for a more widespread use of this additive manufacturing technique, material data should be obtained and evaluated with respect to the influencing manufacturing factors. In the case of Ti6Al4V alloy, the fatigue performance can be highly susceptible to the process related issues, such as build direction, porosity and surface condition. This study was undertaken to examine the fatigue life of Ti6Al4V specimens manufactured by Direct Metal Laser Sintering (DMLS) technique and to investigate the influence of the surface state on the fatigue life. A high degree of anisotropy in the fatigue performance associated with the specimen build orientation was determined.

The Mg-5.6Gd-0.6Y-0.4Nd-0.2Zn-0.2Zr (wt. %) alloy was prepared by metal mold casting. Then the alloy was subjected to hot forging. The microstructure and mechanical properties of the solution-treated, hot-forged and aged alloy samples were studied. The affects of deformation processes on the microstructure and mechanical properties were discussed, and the strengthening mechanisms of alloy were also investigated. The results revealed that the coarse second phases distribute along the dendrite boundaries in the solution-treated alloy. After hot forging, the second phases were broken into small particles and the grains get uniformity. Tensile test results showed that the strength of alloy was greatly improved after hot deformation processes. The forged alloy showed remarkable age hardening response at aging temperature of 180°C. The peak hardness was obtained by the time of 72h. The ultimate tensile strength and yield strength of the peak-aged alloy were 275MPa, 181MPa at room temperature, and 209MPa, 127MPa at 300°C, respectively. The high mechanical properties were mainly attributed to the fine microstructure and fine dispersed metastable precipitates in the matrix.

This paper focuses on verification of experiment of thermoelastic stress analysis by using numerical solution. Thermoelastic stress analysis is noncontact technique to obtain thermograms, thermographic images of the stress fields, by using an infrared camera. In the elastic part experimental results can be used to determine the value of the first stress invariant under adiabatic conditions. The experimental part is dedicated to the postprocessing of the measured data. Numerical solution was performed by finite element method in two softwares: ANSYS and ABAQUS.

At present commonly used conventional materials are substituted by materials of better mechanical qualities. For example highly alloyed steels with chromium, cobalt and nickel alloys, titanium and titanium alloys belong to this group. Titanium and its alloys also belong to the group of hardly machinable materials thanks to its good chemical and physical properties, such as high strength, high corrosion resistance, low density, deformation resistance at high temperature and at the same time low thermal conductivity that unfavourably affects the process of machining. Despite its more complicated machining, titanium together with its alloys are widely used in the aerospace, aviation and automotive industries and, last but not least, in biomedicine. Biologically compatible materials are used for production of implants in medicine from comercially pure titanium TiGr2, TiGr5, nanostructured commercially pure titanium nTI and titanium alloys TiNbTa. As there is a need to produce still smaller and more complex implant with extraordinary accuracies, there arises a strong necessity to understand the process of their machining. We have already published experimentally gained knowledge on turning and milling of stated materials. In this paper we aim to inform about machinability of these materials in drilling.

The Al-brasses are considered corrosion resistant technical materials especially used in pipe systems in energy industry. They are mostly exposed to flowing liquids environments where they are loading chemically and mechanically and their lifetime in practice condition quite vary. The aim of our research work is to compare corrosion and mechanical properties of four Al-brasses from various producers. The Al-brasses have very similar chemical composition but differ in microstructure, surface state what affect their corrosion and mechanical behavior. By chosen experimental methods and analyses the effect of the mentioned parameters are investigated.

The correct determination of the shelf mass including content is very important for the proper function of a universal shelf stacker (USS) drives life and construction USS so that these elements were not overloaded. Weighing can be done by direct methods using various sensors tension and compression but also the indirect method, by the torque sensing of current frequency converter, which controls the speed of the three-phase asynchronous motor. This method does not require any additional construction or adaptation or additional sensors or electronic evaluation system power operation. Weighting method of shelf in USS is based on the fact that the torque converter current is proportional to the sum of the weight of the shelf and the extractor and its value provides almost every frequency converter. In contrast to the direct weighing method of the shelf it is obvious economic advantage of this method and the accuracy is sufficient for the operation of USS.

The microstructure, the phase constitution and the tempering charts of Cr-V ledeburitic steel Vanadis 6 subjected to sub-zero treatment with various soaking times in liquid nitrogen have been investigated. The microstructures have been characterized using the light microscopy, scanning electron microscopy and X-ray diffraction. The hardness has been evaluated by Vickers method. The matrix is martensitic with certain amount of retained austenite, irrespectively to the time of sub-zero treatment. The amount of retained austenite, however, decreases up to the soaking time of 17 h and then remains almost constant. The microstructure of sub-zero treated steel contains enhanced portion of small globular carbides, as compared to conventionally heat treated material. These particles have a size of around 100 nm in most cases. The as-quenched hardness manifests a moderate increase due to the sub-zero treatment. The hardness decreases during subsequent tempering and this decrease is more pronounced in sub-zero treated samples.

Results of signals analysis was done using wavelet transform, which have different curves of wavelets and depend on the basic wavelet, which were applied. Thus, it is sometimes not possible to conduct a wavelet transform of a given profile with the use of any basic wavelets and to obtain results that are similar to the measured signal. The aim of this was work was an optimization of a basic wavelet selection used for an analysis of surface roughness. In the work an analysis of Abbot-Firestone curve parameters was performed on subsequent decomposition levels and for various basic wavelets.

The Al-10Si-21Fe and Al-20Si-16Fe (wt.%) alloys were prepared by short-term mechanical alloying and subsequently compacted by spark plasma sintering. Prepared samples were characterized by ultrafine-grained microstructure with average dimensions of each structural component that does not exceed 200 nm. This resulted in excellent mechancial properties e.q. hardness and compressive strength. Hardness of both prepared alloys reached almost 400 HV5 and remained the same value even after 100 hour of long-term annealing at 400 °C. The Al-10Si-21Fe alloy reached ultra-high compressive strength of 1033 MPa. The casting Al-12Si-1Cu-1Mg-1Ni alloy, generally considered as thermally stable, was used as a reference material. Even the reference materail was thermally treated by the T6 regime, it exhibitted lower mechanical properties compared to the investigated alloys event at laboratory temperature. During annealing, the reference alloy significantly softened reducing its initial compressive yield strength and compressive strength from 430 MPa and 680 MPa to 180 and 498 MPa, respectively. Additionally, hardness reduction by 50 % to the resulting 63 HV5 was observed. Compared to this results, the investigated alloys maintained theirs high initial hardness and compressive strength suggesting excellent thermal stability.