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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.

For a variety of engineering technologies, machining has a specific position because it is a technology that meets the highest requirements on accuracy and quality of products and involves processes that are final, i.e. the last in the production processes of parts machining. Therefore, these processes largely affects the final shape and dimensional requirements of high quality components and hence their performance characteristics, particularly the accuracy and durability. Such production methods designed to achieve high dimensional and shape accuracy is grinding and other finishing methods (superfinishing, polishing, lapping) involved in a high percentage of the production of components whose quality can not be achieved by other technologies, eventually very difficultly. Lapping and about influence of modification of production parameters on quality of lapped surface after lapping. In the experimental part were taken measurement of roughness parameter Rt. From measured values was evaluated which production parameters are useful and economic preferable by demanded reduction of production time and by keeping the roughness parameter at Rt = 2 μm.

A model twin-roll cast Al-Mg-Sc-Zr alloy was prepared and the evolution of microstructure during a step-by-step isochronal annealing was characterized by electron microscopy and light optical microscopy. Inhomogeneous structure with significantly finer grains in the middle of the strip is generated by casting. Subsequent annealing up to 550 °C does not alter this grain-size mainly due to the presence of a fine dispersion of Al3(Sc,Zr) particles, which forms at annealing temperatures below 300 °C. Although these particles coarsen and partially transform at higher annealing temperatures their strengths as recrystallization inhibitors is sufficient to prevent the microstructure from a coarsening. Nevertheless, the beneficial contribution of fine precipitates to microhardness is fully suppressed by the annealing at high temperatures.

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.

This article is focused on influence of finishing operations on the surface quality of polymer products. Finishing operations are the necessary part in the production of injection mold cavities. Surface quality of cavities is reflected to quality of future polymer products. Therefore, it is very important to use appropriate finishing operations and its technological conditions from the aesthetic point of view. However, it is not always necessary to use time consuming and most expensive finishing operations, because the polymeric products are not able to achieve similar surface quality as cavities. The different surface quality of injection molded parts can be also expected using various supramolecular structure of polymer (amorphous, semicrystalline). Supramolecular structure of polymer determines the future properties of product as well as the distribution of the individual macromolecules in the polymer chain. Divergent distribution may result to achievement of different surface quality of injection molded parts. This research is focused on finding an influence of supramolecular structure of chosen polymer on the surface quality of polymer product.

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.

Owing to its magnetic properties, pure iron is among materials investigated with a view to their use for improving existing memory media. Experimental equipment made of pure iron is prepared by using lithographic methods and magnetron sputtering, putting specific technological requirements on the input material. The non-conventional method of wire electrical discharge machining (WEDM) was used for the pure iron target in order to meet those requirements. The present study was devoted to the topology and morphology of the iron target machined by the electrical discharge method. Morphology was examined by scanning electron microscopy (SEM) as a method capable of visualising the contrast between the pure iron and the copper from the electrode material diffusing on the machined surface. Energy dispersive X-ray spectroscopy (EDX) was used to analyse the local chemical composition. The machined surface topography was examined based on its areal and profile parameters.

An adhesive bonding technology is limited by a cyclic loading of an adhesive bond. The paper deals with a testing of a low-cyclic fatigue of single-lap bonds reinforced with glass beads (B159, a fraction size 90 ± 20 μm). The aim of the research is a study of a low-cyclic behaviour of structural adhesive bonds by means of a scanning electron microscopy (SEM). The research will contribute to a clarification of the fatigue behaviour (low-cyclic) of structural adhesive bonds. The aim of the study was to evaluate a service life of the adhesive bond in terms of its fatigue loading at a low-cyclic shear test. Values of a pulsating loading for the low-cyclic fatigue tests were chosen from this reason for tested adhesives from static tensile test determined a reference value of a maximum force gained at a statical test according to the standard CSN EN 1465. The number of cycles was 1000 at the 30 % strength reached at the static tensile test of the adhesive itself. The cumulative effect of the shear cyclic loading after 1000 cycles showed micro- and nanocracks in the area of the adhesive. The experiment results did not confirm the assumption that repeated cyclic loading could lead to the premature failure of the adhesive bond.

Magnesium alloy WE43 is well known for its low density and good mechanical properties. It has also fair corrosion resistance and relative usability up to 300 °C. All those properties are connected with the content of rare earth elements and determine this alloy not only for automotive and aviation industry, but also for applications as biodegradable materials. In this work, WE43 alloy prepared by powder metallurgy methods is characterized. Final products are prepared by cold uniaxial pressing with subsequent extrusion or spark plasma sintering (SPS). Present paper deals with the characterization of processing methods used for the WE43 alloy preparation and also the characterization of prepared WE43 products as themselves.

Approximately an equiatomic alloy of nickel and titanium is known as nitinol. Nitinol possesses a lot of interesting properties such as shape memory, pseudoplasticity, superelasticity and corrosion resistance. NiTi alloys are usually industrially produced by melting process, but the products have not good quality and purity. Powder metallurgy with reactive sintering is considered as one of the route of production of NiTi alloys. However, the other phases are formed during this process (Ti2Ni, Ni3Ti). The presence of Ti2Ni phase is unwanted in this alloy. It is stabilized by oxygen and its main disadvantage is brittleness. In this work we prepared NiTi shape memory alloys by Self-propagating High-temperature Synthesis (SHS). Results showed the possibility of modification of the phase composition by alloying with other elements, which have higher affinity to oxygen. Carbon was found to reduce the amount of undesirable Ti2Ni phase, while in presence of zirconium this phase reduces its hardness which implies the loss of brittleness.

Extrusion process parameters play key roles in aluminum profile extrusion processes. In this literature, by using Box-Behnken experimental design to arrange the simulations using the ALE software HypereXtrude, Response Surface Methodology (RSM) were applied to study the simulation results and discuss the effects of five process parameters, namely billet diameter, billet preheat temperature, die temperature, container temperature, and ram speed, on the outlet velocity distribution uniformity of the profile named an Upper beam on the Train. The interactions between the five parameters also were investigated. Additionally, a second order response surface model between the extrusion process parameters and the evaluation criterion of outlet velocity uniformity was established. An optimization of the process parameters with the purpose to find the most uniform outlet velocity distribution was carried out based on the response surface model. The results show that the three parameters, namely billet diameter, ram speed and die temperature, have significant impact on the outlet velocity uniformity. And there are obvious interactions between these three parameters. After the subsequent optimizations, a more uniform outlet velocity distribution was obtained, and the final acceptable profiles were produced.

The article presents results of M7C3 carbides stereological parameters measurement and wear tests of chromium cast irons. There are two types of material were compared: not inoculated chromium cast iron and the same material about 4% addition of titanium by weight. The samples for studies were taken from casting formed by pouring into ATD-Is tester mould. Then they were properly prepared for testing. Stereological analysis was conducted in ImageJ software, where the following parameters of carbides was measured: area, width, length, perimeter, and circularity. Wear test was executed using pin-on-disk method on Tribotester 3-POD. Results of research shown that Ti addition results in formation of TiC carbide, which is an underlay for crystallization of M7C3 carbides. The effect of this was the finer grain of M7C3 and the lower weight losses during abrasion.

The goal of this contribution was to describe the microstructure and properties changes of difficult to cut materials after turning. Surface residual stresses, roughness, microstructure of AISI 304 type stainless steel were studied as a function of side rake angle o. Residual stresses and phase composition of surface and sub-surface layers were determined using X-ray diffraction techniques. The presence of strain-induced martensite was investigated using Barkhausen noise, optical microscope, and microhardness measurement.

The aim of this work is concerned with a problematic adhesion of polymer materials on the surface of processing tools. Such phenomenon plays especially an important role in production of rubber components which creates an additional and considerable costs associated with mold cleaning. However, the origin of contamination is still not fully known yet. From production point of view, the attention should be paid to three fundamental aspects: processed material, material of processing tool, and processing conditions. This study describes the results of mold's surface contamination during processing a rubber compound in terms of material and surface treatment. A method of spectral analysis in terms of FTIR was used for proper examination of this problem.

TRIP (transformation induced plasticity) steels are low alloyed steels with multiphase microstructure consisting of ferrite, carbide-free bainite and retained austenite. They are typically produced by thermo-mechanical treatment, which involves the hold in bainite transformation region. The hold ensures enough bainite in the final microstructure and also helps to stabilize higher amount of retained austenite. Due to transformation induce plasticity effect; TRIP steels possess very good combination of high strength and high ductility. In response to industrial demands, C-Mn-Si and C-Mn-Si-Nb TRIP steels were subjected to thermo-mechanical treatment with continuous cooling which corresponded to real rolling mill processing of the steel with similar chemical compositions. Typical TRIP microstructures with 10-15% of retained austenite were achieved for both steels after optimization of cooling schedules. However, cooling by two different cooling rates had to be applied to C-Mn-Si steel to obtain the convenient microstructure. Beneficial effect of Nb micro-alloying on low sensitivity of TRIP steel to variations in cooling parameters has been found out. Mechanical properties of the most convenient microstructures were very promising, ultimate tensile strength reached 850MPa with ductility A5mm around 25%.

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.

Titanium alloys are used for the manufacturing of femoral heads for orthopaedic implants. Poor machinability of these materials, especially at high speeds, creates the need for more detailed investigations on this subject. The at hand study analyzes the construction of 3D Finite Element Method (FEM) models pertaining to the manufacturing of femoral heads made from Ti-6Al-4V. For this purpose a commercial FEM programme is employed, specialising in machining modelling, namely AdvantEdge. The validation of the model is provided through experiments on actual femoral heads cut in a CNC lathe at high cutting speeds. Comparison between experimental and numerical results on cutting forces and chip morphology exhibits a good agreement, indicating the success of the proposed models. These 3D models can be used for realistically estimating the influence of cutting conditions on the final product, without performing time and money consuming experiments.

This paper deals with evaluation of the controlling processes service reliability of degradation processes leading to embrittlement, fracture at elevated temperatures, fatigue and fatigue fracture with the possible effect of corrosion and with interaction of all the previously mentioned processes.

The main parameters of the hot forming machines are production capacity and the fatigue life of the used tools. The life of a tool depends on its shape and load. The load depends on the structural design and speed of forming. The goal of our paper is to present the structural optimization and technological parameters design with respect to tool life. This process is applied in the case of the hot forming machine analysis.

The thermodynamic derivatives based on fundamentals thermodynamic space and physical parameters of natural gas influences other variables of pipeline systems such as pressure, temperature, velocity, density, gas compressibility, etc. These variables are crucial for gas pipeline system knowledge and its accurate operation. Fundamental parameters are derived such as Joule-Thomson (J-T) coefficient, isothermal throttling coefficient and isentropic coefficient. They influence gas flow when during the expansion of natural gas in the pipeline, the gas cools down due to the J-T effect and due to the interaction between pipeline system and its surroundings to the conditions at which gas is saturated by water vapour (dew point), and gas is not able to keep excess humidity and its condensation and gas hydrate formation will occur. The article deals with analyses of selected thermodynamic derivatives in the range of chosen temperatures and pressures and also non-isothermal steady-state flow model for pipeline is presented.

For the creation of the bond the treatment of the adhesive bonded surface is essential. The second important factor is the temperature of the environment to which the adhesive bond is exposed. It is a way of a degradation of adhesive bonds. The aim of the research was to evaluate the effect of adhesive bonded surface treatment of alloy AlCu4Mg and increased environmental temperature on a strength of adhesive bonds using two-component epoxies used in the transportation industry. As a bonding material AlCu4Mg was used, whose surface was in the first series mechanically and chemically treated. In the second series tested specimens were without the surface treatment. A destructive testing was conducted at a laboratory temperature 22 ± 2 °C and at increased temperatures, i.e. 40, 60 and 80 ± 2 °C. At a mutual comparison of the mechanical treatment and the chemical treatment of the adhesive bonded surface with un-treated surface, the tensile lap-shear strength increased by an average of 57.24 ± 18.52 %. The results show that there is a difference in the tensile lap-shear strength between the test temperatures in the interval 20-80 °C, the decrease was up to 88 %.

Aluminium and silicon alloys are widely used in practice currently, e.g. in car industry, aircraft industry or in civil engineering. Hence there is increasingly more emphasis placed on research and development of silumins. The aim of this paper is to analyse aluminium alloy, namely the alloy AlSi7Mg0.3. This paper is focused on the effect of particular modifiers and heat treatment on the selected properties of the alloy, especially on structural transformations caused by various modifiers, hardness measurement (Brinell method) and microhardness testing (Vickers method). Four variants of castings (unmodified alloy and alloy modified by chemical elements - strontium, calcium and antimony) were tested. All alloys were compared to the cast of pure aluminium (Al 99.8%). There were moulded four castings from each variant and two castings of pure aluminium. It was casted using a gravity-die casting into a metal mold with a thermal insulation - except of pure aluminium (without thermal insulation).

Aluminium is widely represented material in engineering - one of the possible forms of application is an Al powder, when mutual interaction mainly with polymer matrix creates new materials. In practice, the aluminium powder is commonly used together with a number of reaction resins, e.g. epoxy resins. Such systems can be described as liquid metals, and amongst other options of the application, they are used for quick renovation of the functional areas of machines. In such applications, particularly important are hardness and durability of the composite layer against wear. This paper experimentally evaluate the friction and wear of systems based on epoxy resin with aluminium powder (microparticles), through reciprocating sliding tribotests. Tribological outcomes evidenced a reduction of the friction coefficient when the resin is reinforced by alumium particles, with a concentration of 32% in term of volume fraction.

Usually, the coatings used in industrial applications require post-processing to reach their final shape. However, some of these coatings are difficult-to-cut, mainly because of their high hardness. The present study provides a revision of some experimental investigations on the turning of WC-Co, Stellite, and Fe-based and NiAl alloys. The materials are used for both coatings and sintered workpieces providing insights for conducting turning tests. For the success of the turning process, the selection of the machining parameters is a critical issue. Based on the reviewed investigations, the surface roughness is clearly influenced by the feed rate, expecting higher values than the ones predicted by the theoretical equations. Besides, the increase of both the cutting speed and feed rate leads to a high tool wear. Likewise, the increase of the feed rate leads to higher machining forces. In general, the influence of the cutting speed and depth of cut is less evident. Regarding the machining parameters, usually their maximum values are fixed at low levels: 100 m/min, 0.35 mm/rev and 0.3 mm, for the cutting speed, feed rate and depth of cut, respectively.

A constructional shape of an adhesive bond deals with a mutual position of bonded parts in such way to gain a given contact area. The constructional shape of the adhesive bond finds a practical application at connecting of plain areas that means sheets of metal above all. The adhesive bond strength at connecting the galvanized sheet of metal was significantly lower than at connecting a constructional carbon steel. Results of specimens of wavy-lap bonds showed higher values of the adhesive bond strength comparing with specimens of single-lap bonds. The wavy-lap constructional adjustment proved to be positive at connecting the galvanized sheet of metal. The increase of the adhesive bond strength ranged in the interval 27 to 560 %. The difference in using specimens A (single-lap bond) and B (wavy-lap bond) is obvious from the statistical comparison. It is visible from performed experiment that using the specimen B (wavy-lap bond) led to increasing of strength values of the adhesive bond.

Detection system of infrared thermography technology was designed, taking a non-refrigeration focal plane infrared camera and the pulse flash heating system with high energy as the core. Combining with the performance parameters and structure features of the hardware equipment, integrated control system was designed. Meantime, the cover and reflector for the detection system were fabricated, which improved the uniformity and the utilization rate of energy for the thermal excitation source of the flash lamp. Based on the Delphi program, control, acquisition, processing and analysis system for the infrared image sequence were developed. And defect identification software was also researched which could implement the quantitative calculation and analysis for the parameters of defect size, location, perimeter, area and depth. Finally, experiments for metal and composite with flat bottom defects were carried out by the use of the detection system proposed in this study. The results show that the detection system has the advantages of well controllable performance, convenient operation, perfect detection effect, powerful image processing functions, which can meet the testing demand for engineering application.

Nowadays people spend still more of their life on the road. Vehicles has been becoming increasingly sophisticated and the main direction of their development is placed primarily into the areas of environment, design, safety and comfort. This work focuses primarily on the last-mentioned point, and that's seating comfort and the phenomena with straight influence on the transported persons. Probably with any of car elements, isn't the person in a direct contact to much as with the seat and therefore the seats and their innovation are still in considerable interest of the customers and manufacturers. This work deals with description of the resulting tensions and distribution of the specific pressures in the cushion of a car seat and also describe the creation of an appropriate computational model.
Based on the real transmission data, that was measured during driving a car, has been carried out an experimental measurements of static and dynamic loading of the overall stiffness and response of the system. Subsequently, depending to the real CAD data were compiled the boundary and materials conditions that describe the statical FEM model of the polyurethane cushion. For the quasi static load was carried out the experimental measurements on a mechanical pulsator, that is suitable for assessing the viscoelastic and hysteresis effects inside the materials. The found results have been verified with using the x-sensor on a model of real human back during the scanning of its specific contact pressure.

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.

Lead is traditionally used for completing free-machining materials. This paper deals with newly developed lead free copper alloys. Unfortunately, lead affects the haematological and nervous system. Therefore, materials containing lead represent one of the greatest environmental problems in world production. Research Material Institute in Panenske Brezany (CZ) developed new environmentally friendly cooper alloys. Machinability of these materials was tested at the Department of Machining, Process Planning and Metrology CTU in Prague. Some of the research results related to the machinability from the viewpoint of chip forms, surface roughness, cutting temperature, cutting time in drilling with constant feed force, and forces in cutting are presented.