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The present paper deals with the microstructure characterization of drosses originated during production of a new type of coating called Zinkomag. This coating creates during continuous galvanizing process and it is characterized by addition of 0.8 - 1.0 wt. % Mg and 0.8 - 1.0 wt. % Al in the zinc galvanizing bath. The addition of magnesium in such coatings leads to increasing of hardness, corrosion resistance, and better color adhesion than most common used coatings (GI coatings). In this paper drosses were investigated using AAS, LM, SEM with EDX microanalysis, and XRD.

NiTi is a shape memory alloy used mainly in medicine. Many applications can be also found in industrial sector. Its properties are considerably determined by structure and phase composition. It was found that production by powder metallurgy method leads to creation of required phase NiTi, but certain amount of hard and brittle phase Ti2Ni is also formed. Its presence in the structure affects mechanical properties of the alloy and it might widen the applicability of material to a new industrial branches. Suitable preparation method of composite material NiTi-Ti2Ni with the possibility to control amount of generated phase Ti2Ni would allow regulation of material mechanical properties.

Using of cutting inserts is currently a normal part of the manufacturing process. The article deals with the tool wear evaluation of selected inserts for turning by electron microscopy. Use of electron microscopy helps on closer analysis of machining consequences forthese plates, because the microscope images captured with electronmicroscope have a greater depth of sharpness and can display examined object with greater plasticity. It is yet another way to explore objects and extends the possibilities for obtaining large quantities of information. These analyzes were realized in other experiments performed at the Faculty of Production Technology and Management of Jan Evangelisty Purkyně University in Usti nad Labem. As a experimental material the hardened steel class 16 343 according to CSN 41 0002 has been machining.

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.

Using cutting or forming taps during the production of internal threads represents the basic method of manufacturing these coupling structural components, which - in the case of smaller dimension internal threads - can be encountered in many manufacturing processes. To optimize the cutting process and forming of internal threads, and in favour of the final results of these operations, the right choice of technological conditions, process fluids and methods of their application in areas where the technological process is realized, is needed. An important aspect of the use of process fluids are relatively large operating costs, and in some cases also the adverse environmental effects. Therefore, one of the current trends is reducing the amount of process fluids used during machining operations. At the Department of Machining and Assembly at the TU of Liberec experiments were conducted and various technological methods of production of internal threads during the use of various types of process fluids and methods of their application in the technological process were compared. During machining and molding, technological process, the parameters and properties of the produced internal threads were evaluated.

Modelling of cutting forces is important for understanding and simulation of the machining processes. This paper presents cutting force modelling of data obtained from machining of C45 carbon steel with a coated carbide tool. The model is based on a rather extensive measurement of 270 combinations of cutting tool geometry parameters (rake angle, clearance angle and helix angle), tool wear (flank wear average value), chip thickness and cutting velocity. The model with the friction and cutting component of the cutting force is presented and discussed. We conducted an analysis of the identified model and found a relationship between the increase in tangential and radial cutting forces and tool wear. We concluded that flank wear influences the cutting force acting on the worn tool more significantly than cutting tool geometry. This is caused by changes in cutting edge geometry and the resultant significant increase in the friction component of the cutting force as is shown using the identified model.

The article is aimed on the analysis of the internal damping changes depending on the amplitude of the magnesium alloys AZ31 and AZ91 in as cast state. In experimental measurements was used only resonance method, which is based on continuous excitation of oscillations of the specimen and the entire apparatus vibrates at a frequency which is near to the resonance. Starting resonance frequency for all measurements was about f = 20470 Hz. These mechanisms have been studied by ultrasonic resonant apparatus. Damping capacity of alloys is closely tied to the presence of defects including solute atoms, second phases and voids. The interaction between moving dislocations and point defects is one of the major internal damping mechanisms of magnesium alloys so the precipitates influence the damping capacity and contribute to damping properties.

The article deals with heat transfer in the casting - mould system. There are characteristics of sand and metal mould. The sand mould is a dispersion system, respectively - a capillary-porous body. In sand mould are heat transfers shared by all three ways: conduction, convection and radiation. These individual elementary processes of heat transfer are only theoretical significance, as very often processes are taking place simultaneously in different intensities or interact. The maximum effects of these processes are in a certain temperature range. From temperature 200 °C dominates conduction heat transfer. Between of temperatures 200 to 600 ° C is the effective convection heat transfere. At higher temperatures above 600 ° C prevails radiation heat transfer. This is the consequence, why the sand mould has a lower value thermal accumulation than a metal mould. The metal mould as a result of its character and compactness has a high heat accumulation value. Therefore, in the metal mould cast solidifies faster than the in sand mould. Based on the Newton's and Fourier's laws, there were indicative calculated times of solidification cast of shape plate in the sand and metal moulds. Concurently were made simulations calculations performed solidification of shaped plate through simulation software MAGMA 5. To obtain the corresponding results of simulation calculations, it is important to use the respective temperature-dependent of the thermo-physical variables, including temperature dependence heat transfer coefficient.

The paper describes the influence of metallurgical processing on the microstructural characteristics of spheroidal graphite cast iron. The iron is used for casting the core of double layer centrifugally cast rolls. Low carbon content in the core spheroidal graphite cast iron supporting metastable solidification was eliminated by managing of metallurgical processing of spheroidal graphite cast iron. The metallurgical quality of the cast iron was controlled by using thermal analysis during all time i.e. melting furnace, through modification and inoculation. The metallurgical quality is documented by metallographic analysis, determination of surface proportion and amount of graphite on surface etched specimen. Test rolls were cast in operating conditions in roll foundry Vítkovické foundries, spol. s r.o. Evaluation of melts and microstructures were made in the laboratories of the VSB-TU Ostrava.

This work deals with an impact of abrasive particles used in powder injection molding (PIM) on a surface roughness of the tool. For this purpose, the surface of new mold cavity was compared with the same mold cavity after 2 000 injection molding cycles. Processed PIM compounds contained polymeric binder with around 60 vol. % of metal or ceramic particles (0.1 up to 20 μm). Surface analysis was performed on cavity impressions prepared from a special silicone imprinting substance in two directions by a 3D surface scanner. Investigated parameters were surface roughness (Ra) and roughness depth (Rz) which have an influence on flow instabilities of highly filled compounds such as wall slip affecting the final product quality. Obtained results showed a significant wear of the mold cavity which was statistically confirmed by t-test and F-test parametric methods. A greater part of the mold cavity was smoothed during injection of PIM compounds, while the surface roughness increased near the point gate (runner system) probably due to a high injection pressure in this part of the mold.

This paper deals with the assessment of the procedural gases progressive cooling methods and cooling by procedural liquids at turning technology on the final workpiece surface quality. Turning by using liquefied CO2, liquefied nitrogen and subcooled air supplied through the vortex tube was compared with the turning without process medium (taken as reference conditions) and with two procedural liquids EOPS 1030 and HOCUT 795 B. At evaluation effect of procedural gases there were monitored acting forces, cutting tool cooling rate and the machined layer of the material, cutting tool durability and cut surface quality which was characterized by surface roughness and dimensional accuracy. During the experimental part there were used devices as lathe SU50, piezoelectric dynamometer, the evaluation unit and profilometer. This issue was solved within solving the project TACR - TA03010492.

This paper reports the preparation and characterization of thin transparent nanolayers with phase composition ZrF4 and different modification of SiO2 with special focus on the affecting the surface roughness of the material and the way of exclusion of the thin nanolayer on the surface of the polished aluminium material. The thin nanolayer was prepared by the sol-gel method. The final treatment based on PTFE was applied on the surface of some samples. This treatment is suitable for the increasing of the wear resistance. The films were characterized with help of SEM microscopy and EDS analysis. The surface roughness was measured with classical surface roughness tester. There was published results on this theme but not on the polished surface of the aluminium material. The results from the experiment shows on the problems with application of these nanolayers because there were found a cracks on the surface of the material and deformations of the layer after application of two nanoproduts and PTFE final layer. The surface layer formation is discussed.

Porous titanium implants are increasingly used for excellent corrosion resistance, mechanical properties similar to bone, biocompatibility and good osseointegration ability. The advantages of porous structure are lower density which causes better ingrowth of bone tissue. Changing the porosity influences resulting mechanical properties. Higher porosity decreases the elasticity modulus and tensile strength. Newly developed alloys based on titanium and silicon can be used as bone fillers, artificial interverbal discs, augmentations or dental implants. Titanium and silicon are nontoxic elements for human body, which is very important for biocompatibility. Another advantage of these alloys is that they have an ability to spontaneously create porous structures without pore forming agent. Pores support implant ingrowth. Varying the concentration of silicon influences the porosity of the alloys prepared by reactive sintering. The best mechanical properties were achived in the case of alloys with 2-7 wt. % of silicon.

The aim of this work was studying the effect of the composition and production on mechanical and tribological properties of cobalt alloys. Co-Cr-Mo alloy began to be used for manufacturing dental implants, but nowadays they are successfully used for the production of orthopaedic implants thanks to better wear resistance than is offered by titanium implants. However, there is still ongoing effort to even more improve the wear resistance and other properties of cobalt based alloy. The aim of this research was to find a suitable combination between composition and production, which would increase the wear resistance, keeping the other mechanical properties at least at the same level. Standard Co-Cr-Mo alloy and also Co-Cr-Mo alloy with various alloying elements, specifically Nb, Ti in an amount 5 wt%, were prepared by casting and also mechanical alloying followed by compacting method "Spark Plasma Sintering". The influence of production route as well as influence of alloying elements on the microstructure, mechanical and tribological properties were observed. Based on the obtained results, the Co-Cr-Mo-Ti alloy production by casting seems to be most suitable, because the addition of titanium has greatly improved the wear resistance. However, it is necessary to perform many other tests, especially tests of corrosion resistance and biocompatibility.

This paper deals with non destructive evaluation of surfaces via progressive method based on Metal Magnetic Memory (MMM). The paper reports about the physical background of this technique as well as presents specific results of some tests carried out on industrial and laboratory surfaces. This method seems to be promising techniques for fast and reliable monitoring components exposed to the surface modification as well as degradation under the external mechanical and other loads. The paper also discusses some advantages and disadvantages of this technique and presents some examples in which real components are monitored by the use of this technique.

These days are more and more posing claims for the highest quality of castings from the aluminium alloys and for the lowest weight of these castings. Thus for complex material (in this case alloy) utilization it is very important to monitor its behavior both during production (chemical composition, metallographic evaluation of the structure, observance of thermal treatments temperatures, refining and degassing of melt and so on) and also during its loading. This papers deals with the monitoring changes of stress on the testing samples surface arising from the force loading. As a loading there was a bending momentum at the testing samples (rods) from the alloy AlSi7Mg0,3 which was poured into the metal mould after the different thermal treatment methods. Bending momentum increased up to the expressive deformation of the tested sample. Results were also completed by the depth profile of the residual stresses which were measured by means of the X-ray diffraction (X-ray tensiometry analysis) namely for all thermal treatment methods. Moreover in the depth profile there was also performed the qualitative evaluation of the structure by the back-reflection Debye-Scherrer method.

3D printing of metallic powders is a relatively new but increasingly used technology in a wide range of sectors. Design engineers are responding flexibly to new opportunities for production and components for 3D printing and are designing with respect to the advantages and limitations of this technology. Through the additive method of production, we can produce very specific components with complex shapes, both internal and external, which cannot be produced by conventional methods, thereby opening up new possibilities both in functional components and in their design.
This paper deals with the influence of critical parameters of metal laser sintering of metallic powders, particularly tool steel, on the geometrical accuracy of a component. Based on selected critical parameters, a component was designed that was printed on different devices and subsequently evaluated in terms of accuracy, surface quality and material properties.

Wire electrical discharge machining (WEDM) is an unconventional technology of machining that uses physical phenomena for material cutting. During wire electrical discharge machining craters are formed on the workpiece surface, and blended and molten material of both workpiece and wire electrode get stuck here due to diffusion processes. The study deals with the assessment of the influence of wire feed rate on quantitative and qualitative evaluations of craters on the workpiece made of X155CrVMo12-1 alloy tool steel. The diffusion phenomena that had occurred on the surface during the process of cutting were studied using light microscopy. Attention was also given to the detail study of the used brass electrode where the level of wear and degradation in terms of the quality of morphology were studied after the process of cutting.

In order to improve the transmission efficiency and the service life of ordinary cycloid gear, 5 kinds of new cycloid gears with variable cross section are devoleped based on the principles of traditional cycloid drive. These new cycloid gears include concave cycloid gear, drum cycloid gear, spherical cycloid gear, oblique cycloid gear and cone cycloid gear. The general mathematical equations of these new cycloid gears are obtained and the characteristics of these new cycloid gears in transmission applications are analyzed in detail. A new method on the end milling tooth profile surfaces of cycloid gear using ball end mill is proposed. 5 axis numerical control simulations of these cycloid gears are conducted and the tool paths of machining cycloid gear are obtained. 5 kinds of cycloid gear with variable section are machined on five-axis CNC machining center, which verifies the correctness of the NC program. The study will provide a new way of designing and machining cycloid gear.

Mechanical properties and chemical composition of aluminium alloys were investigated by automated ball indentation tests, scanning electron microscopy and energy dispersive X-ray analysis.
In this work, Automated Ball Indentation (ABI) technique was compared with the standard mechanical tests. ABI method is based on the load controlled multiple indentations into a polished surface by a spherical indenter. The indentation depth is progressively increased to a maximum user specified limit with intermediate partial unloading. This technique allows to measure the yield strength, stress-strain curve, strength coefficient and strain hardening exponent.
For all these test materials and conditions, the ABI derived results were in very good agreement with those obtained from conventional standard test methods.

Water jet technology material cutting is analyzed from the point of view of environment, namely of an impact of noise to production process working conditions. Except noise, vibrations also influence working environment but this problem in this text is not dealt with. Measuring of noise level was focused on one working shift at a production workplace of a firm WATING Prešov. Two workers were chosen for this puprouse - operators who operate two cutting desks during a common working shift. In accordance of given methodics, measuring microphones were placed on the operators and on selected places of the workplace. The recorded results of measuring were evaluated and consequently steps for noise elimination during water jet cutting process were accepted.

Additive technologies belong to modern trends in production of prototype components. They include e.g. sintering of powders with a various chemical composition, granularity, physical, chemical and other usable qualities. There belong to additive technologies especially a technology of Rapid Prototyping that use various principles to make components. According to the used technology photopolymers, thermoplastics, a specially modified paper or metal powders are used in a Rapid Prototyping machinery.
An article deals with a characteristic, concept, calculation and production of a prototype model of an axial fan that enables quick build-up time of fan turbine speed. Production of the axial fan is realized by an additive technology of Rapid Prototyping using a method of Fused Deposition Modelling - a 3D printer Fortus 360mc. The article describes individual development stages from the concept to production itself including a final visualization of the prototype model of an 11-blade axial fan.

Absolute length calibration of gauge blocks traceable to the definition of meter is an important task of the national metrology institutes responsible for providing reliable length artifacts for industrial use. The length of a gauge block (henceforth, represented as GB) is defined in ISO 3650 as the distance between its one measuring face and the surface of an auxiliary platen on which the other measuring face has been wrung. Accordingly, in central length calibration of K-grade GBs using interferometry, it is required that they be wrung onto an auxiliary platen whose characteristics are the same as the measuring face of the GBs. According to this definition, the length of a GB consists of its mechanical length between two faces and the wringing film thickness. This definition is practical and reasonable in many cases because GBs are used as length standards with wringing. Also this calibration method has the advantage that the thickness of the wringing film is propagated appropriately when lower grade GBs are calibrated by comparison to higher grade GBs via a mechanical comparator. In terms of this paper is briefly described interferometry method of gauge blocks calibration. The paper was written in conjunction with Czech Metrology Institute.

3D printing is a new and advanced technology of material processing, which belongs to additive manufacturing process. Products with complex geometries can be produced quickly with high precision from powder materials on the base of a CAD-model. Layers of powder particles are successively molten by laser beam. There are several metallographic issues connected with 3D printed microstructures. Laser beam processing is usually accompanied with high heating and cooling rates and therefore also with high thermal gradients. This is the reason why nonequilibrium phases and structural components can occur in the final microstructure. The microstructure could be also finer in comparison with the one produced by standard manufacturing methods. Porosity of the final microstructure is also an important factor, as it might deteriorate mechanical properties of the product. Thorough metallographic analysis of 3D printed materials is therefore necessary to ensure high quality of final components.

To increase the intensity of cooling the unconventional methods can be used, which enable to achieve quick and steady heat transfer from the injection mould and from the plastic product. This paper is devoted to the cooling method based on high cooling potential of liquid carbon dioxide that is included among the unconventional methods of mould temperature control system. The main objective of this paper is to evaluate the applicability of cooling with using liquid CO2 in the injection mould with regard to several aspects that have a direct impact on the final cooling efficiency. The practical experiment deals with the design of the shaped mould insert with the incorporated progressive cooling system by means of CO2 and its comparison with conventional tempering by water. The study is based on evaluations of the temperature profiles reached from thermocouples located in three positions in the injection mould and analysis of temperature fields measured on the surface of the product after its removal from the shaped insert. All the analyses were carried out for three cooling modes and before individual testing steps the technological parameters of cooling were optimized.

A machining method of end milling cycloidal gear using ball end mill is proposed based on the analysis of grinding and side milling ordinary cycloid gear. The machining principle of end milling cycloid gear using 5-axis CNC milling machine is analyzed and the geometric model of end milling cycloid gear is established. At the same time the NC simulation of the machining process is conducted. End milling ordinary cycloid gear is conducted using five-axis machining center and it verifies the feasibility and scientific of end milling ordinary cycloidal gear. The machining precision of the cycloid gear is measured using a three coordinate measuring machine, and it verifies the reliability and usefulness of the machining method. It proves that the machining method can achieve grinding precision. Using end milling instead of grinding cycloid gear is achieved in order to improve the machining efficiency.

The article deals with the influence of the holders speed on the final radius size of the cutting edge. The reason why is investigated radius of cutting edge is that its size affects important parameters in machining process. For example, these parameters are geometrical accuracy of machined components, cutting tool life and stability of machining. Futhermore, it is forces on the cutting edge and thermal influence on the tool. In the experiment five variants are used, prepared by drag finishing. The main variable parameter is holder speed. The aim is to confirm or refute the imput idea. This idea is based on the theory, that the higher holders speed will increase the intensity of drag finishing process. The results are measured and analysed on microscope IFM G4.

The manufacture of die forgings from Al-Mg-Si type alloys is one of important topics of material and forming technology development. One of innovation factors affecting the forging technology is based on the use of continually cast rods instead of extruded ones. This change of technology is, however, connected with some problems concerning the structure, an inhomogeneous surface layer, surface morphology of cast rods and increased flow stress of the cast structure as well. The present paper deals with some aspects relating to the inhomogeneity of structure, intermetallic phases and thermomechanical treatment. The investigation of the cast and extruded structure was carried out with the help of optical and electron microscopy.

Even though the thermochemical treatment is thought as a typical domain of ferrous alloys, there exists a series of technically important processes in the case of non-ferrous metals. Thermochemical heat treatment processes can be divided to two main groups to the manufacture of wear resistant layers and the corrosion protection, mainly against the high-temperature corrosion. This paper summarizes current knowledge in this field and describes the realization of the processes and examples of practical applications.

Composite systems are promising types of materials which due to the mechanical properties are used in a variety of industries. The resulting mechanical properties of these materials are defined by the properties of individual phases and their mutual interaction. When defining these factors it is possible to use microscopy and non-destructive methods. This paper describes the use of fluorescence confocal microscopy to describe the porosity of thermosetting resin forming matrix of systems filled with particles of glass powder. Confocal microscopy is also used to describe the surface of the steel adherent before application of the composite system when evaluating shear strength when the surface roughness parameters can be considered as key indicators influencing interfacial interaction. Electron microscopy was used to describe the size and shape of the particulate filler and mutual interaction of the filler and the matrix. Use of microscopy showed adequate interaction between the glass powder and epoxy resin. Inclusion of glass powder into epoxy resin did not lead to a statistically significant change in shear strength on steel adherent.