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In particular, the quantitative and qualitative results of the technological process are in most cases determined by the level of finishing operations, which include in particular grinding. It is characterized by high precision, the accuracy of geometric shape and generally very good quality surface. One of the factors to achieve the desired quality of finished surfaces, in particular, knowledge of the effect of temperature of the contact surface of the grinding wheel and the ground. In the article is the methodology of the quantification of the impact of cutting parameters on the temperature of the grinding. Another requirement is the right choice of other cutting parameters, to guarantee the achievement of the required accuracy dimensions and shape, increase performance and decrease the temperature of the contact of the cut surface with a grinding wheel.
The result is the desired surface integrity and the exclusion of undesirable residual stress in the lustre of the surface. In the case of the quantification of the individual characteristics of the grinding on the optimization of the grinding process, it is possible to achieve this objective

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.

Rare earth elements in magnesium alloy enhance mechanical properties, corrosion resistance, and heat stability up to 300 °C. Those enhancements with low density of magnesium determine this alloy for aviation and automotive industry. Magnesium alloys are also considered as materials for biodegradable implants. In this field there are required good mechanical properties and fair corrosion rate. In this work, WE43 alloy prepared by powder metallurgy with different conditions of sub-processes is prepared. Milling, cold uniaxial pressing, spark plasma sintering (SPS) and extrusion processes are used for sample preparations. Structure and mechanical properties of prepared materials are characterized.

Currently at our department - Department of Engineering Technology - Technical University in Liberec), we are under-tracking properties of copper alloys. This article is dedicated of the brass (Cu-30Zn), which is used for production of decorative castings. With production of decorative castings deal various foundries in the Czech Republic. The staff of these foundries for long periods gained a lot of experience in metallurgy and preparation of the copper alloy melts. In terms of our foundry there is little available literature data, which would characterize the crystallization and solidification of castings produced from single and multicomponent brass. Our department is involved in research of copper and its alloys. This article contains a description of crystallization of copper alloys (70%) - Cu-30Zn and proving phase analysis structure of the production of test casting shape of desk in the sand mould.

Paper deals with problems of nanoparticles and nanomaterials applied in technical practice. In this time, we are looking for and examining ways of their best properties utilization. When being applied on the base material (metal, plastic, glass, incl. paper, cloth, etc.) In the form of very thin layer, then the base material can obtain very different properties, mostly advantageous, including improvement of their mechanical properties. To obtain these properties, it is necessary to apply nanomaterials in the form of very thin layer and for this purpose we need extremely fine granular nanoparticles that can be produced by means of fine milling technology. Resulting size, structure and shape of individual particles grains have the deciding influence on the successful application of these nanomaterials layers.

Austenitic stainless steels are widely used for various biomedical applications because of their biocompatibility, high resistance to uniform corrosion and suitable mechanical properties. However, they are prone to local corrosion in aggressive halides environments. This article focuses on the effect of fluoride added to physiological saline solution (0.05 % NaF resp. 0.5 % NaF + 0.9 % NaCl solution) and on the effect of fluoride containing mouthwash (0.05 % NaF) on corrosion resistance of AISI 316L surgical steel. Evaluation is based on results of 42-days exposition immersion tests performed at the temperature of 37 °C (REM observation of attacked surfaces, mass losses of specimens) and on the results of the electrochemical cyclic potentiodynamic polarisation tests performed in the same solutions at the same temperature.

Iron has a low solubility in aluminium solid solution even at elevated temperatures and forms brittle intermetallic phases with needle-like or platelets-like morphology when it is produced by conventional casting technologies. These phases have a detrimental effect on mechanical properties. Therefore with increasing significance of recycling and also amount of aluminium scrap that needs to be recycled, it is necessary to find a promising ways of processing such waste materials. Powder metalurgy leads to intensive microstructural refinement, increases solid solubility of alloying elements and overall to improvement of mechanical properties. Hence, it belongs to promising alternatives for proccesing aluminium materials with increased amount of iron. Aluminium alloy with 17 wt. % iron was prepared by centrifugal atomization and consolidated by spark plasma sintering followed by hot extrusion. The microstructure and phase composition of compact samples as well as mechanical properties were studied. Fine microstructure has been achieved by centrifugal atomization and consolidation by spark plasma sintering in combination with hot extrusion. Compression strength was 565 MPa with remarkable ductility reaching almost 35 %.

This paper investigates the influence of Artificial Neural Network (ANN) architectures on its prediction capability when machining nickel based super alloy. The ANN was employed to determine surface roughness parameter Ra through cutting conditions, tool wear and process monitoring indices such a cutting force components. The ANN structure was optimized by methods like a reduction of input vector parameters, dimensions of input data pattern, combined reduction and modification of hidden layers. Calculated and experimentally measured values were compared for each optimized ANN model. The work concludes that optimization of ANN has significant influence on prediction capability and accuracy for the task proposed.

The article presents comparison of optimization methods applied to operation of the heating plant. Optimizing problems are possible to solve with using of methods of the linear programming (LP) or nonlinear programming (NLP). In the paper method of differential addition (LP, NLP), method of characteristics (LP), simplex method (LP), method of Lagrange multipliers (LP, NLP) and method of hyperplane in n - dimensional space (LP, NLP) are presented from point of view of requirements for designing and modifications of the program, requirements on system memory and computation time, comparison of the optimizing methods for loading of the thermal power machines and devices.

In the production of polymer parts, great emphasis is placed on the quality of polymer product in terms of dimensional accuracy and optimally surface quality. Achievement of high surface quality of injection molded products correlate to the high surface quality of core or cavity in injection molds. This surface is copied during injection of polymer material. The kind of polymer material and its rheological properties can strongly influence this surface copying. Production of cores and cavities takes in the manufacturing process a considerable part of time, where some finishing technologies are more economically and time consuming than other processes. Thus, it is necessary to choose an appropriate finishing operations considering cost of injection mold, which is reflected in future price of polymer product. This paper experimentally examines the influence of the surface quality of mold cavities and rheological properties of polymer on the surface quality of injection molded product.

This article deals with the influence of different specific pressures on the heat flux from the casting into the mould. The determination of the heat flux at different crystallization conditions will be the basis for the simulation calculation of the solidification with the crystallization under pressure.
The article presents the results of the measured temperatures inside of the mold and casting by influencing of the crystallization pressure of 100 MPa. For comparison, results are also presented in gravity cast specimens. Also are presented pictures of microstructure that were observed near the surface of the casting. On the basis of the measured temperatures inside of the mold are calculated as a value of the heat flow from casting into the casting mold. The results of heat flow correspond with the evaluation result of the microstructure.

From the viewpoint of residual stresses and microstructure of ground surface, Inconel 713 superalloy is an attractive material since it is frequently used in high temperature gas turbine applications where residual stresses are relevant for service life. The goal of this contribution is to find whether there exists a relation between grinding parameters and final surface integrity parameters such as residual stresses, roughness, crystalitte size, and generally, microstructure. Highly productive creep feed grinding has been applied to produce both simple flat areas and complex fir three blade root. It has been found that the used grinding method lead to very thin deformed layer on the surface with compressive residual stresses and fine crystallites. Moreover, the detailed analyses have been carried out in order to pinpoint plausible reasons behind crack origination.

The article is deals by an introduction to the theory of impact load for thin plates. This is the plates that are characterized by a structure which is bounded by upper and lower surface plane. These surfaces are spaced by a distance h, which is substantially smaller in comparison which other dimensions of the plate (a × b). The impact causes a deformation of the plate which is vibrated. The deformation is only within the limits of Hook's law. Therefore there is not permanent deformation of the plate. In the plate is induced shear stress, bending stress and shear forces. The second part of the article is focused on the numerical solution of thin isotropic aluminium plate which is made from AL 99.9. This plate has a dimension of 100 × 100 × 2 mm. It was solved the deformation of the plate after the impact load which were produced in the centre of the plate by FEM in software ADINA. By results was a graph of the deformation, velocity and acceleration of response wave in the material.

This paper aims to design a control jig for cutting inserts measurement. These inserts are made from standardized inserts by grinding. The control jig is intended to be used on two different types of measuring devices and it has to meet the functional requirements of these devices.The intoduction describes specific functional requirements on the jig, provides information about measuring devices and examples of cutting edges grinded on inserts. Next part describes the design of several variants of jig parts and reasons for their application. Paper is focused specifically on design of jig body variants, description of measuring arm and the way of clamping of inserts in the control jig. The measuring range is described for each of proposed variant. In the closing part of the article particular variants are compared according to their suitability, stability during measuring and range of serviceability for measuring of the inserts.

In this paper the mechanical behaviour of structural two-component epoxy adhesives in T-joints is experimentally investigated. Laboratory experiments were performed on standardized test specimens of structural carbon steel S235J0 made according to standard ČSN ISO 11339.
The aim of experiments was to confirm or disprove a hypothesis about a possibility to increase the adhesive bond peeling strength by means of an interlayer from glass fibres.
The research was focused on an effect of an improving a resistance of the adhesive bond stressed by peeling by adding an interlayer created by fabric from glass fibres. The testing of these properties was performed in accordance with standard ČSN EN ISO 11339. An epoxy resin was used as the adhesive for connecting adherents created by sheets of steel. The fabric from glass fibres of the type E in a plain weave was added as the reinforcement for creating the composite bond. For optimization of properties of the composite bond it was used various weight in grams of fabric in the extent of 80, 110, 160, 220 g/m2.

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.

This article describes robotised welding workplace and gathering information from the workplace. It focuses on the collection of information to wear welding pliers. The workplace will be linked to a database, which will dispose of the measured data, which we will be able to through the web server we can look on the Internet, anywhere in the world. The advent of the Internet has significantly changed the environment of the production and education. The implementation of Web technology moves to integrate into production systems virtual races. With this rapid information technology we can exchange data on production and products all over the world 24 hours a day, and regardless of the place and time. The Internet allows for effective cooperation and interaction at a distance on a global scale. Through the internet it is possible to provide the operating instructions without physical presence of the production systems. The Internet not only allows quick access to its ability, but also their rapid transfer. Local production and regional trade is becoming global. The relationships between suppliers, producers, consumers, which have so far been "personal" to become virtual. Through the Internet, you can run the activities of the production system, inform all interested parties about what is happening and what has happened.

The article presents investigation of the trybological properties, particularly dry friction and friction using a process fluid, of friction pairs of steel ball against titanium-aluminium base nanomultilayer (NML) coatings. The coatings are deposited by cathodic arc evaporation of both pure titanium and aluminium with eighteen percent silicon cathodes. Each multilayer structure consists of 49 bi-layers. The external deposited layeris with five times longer growing period. The coatings are deposited at the temperature of 400°C and the work pressure of 2 Pa. Polished steel discs (Ø 20 mm × 5 mm thick) are used as the substrate material. The measured dry friction coeficients are in the range of 0.216 - 0.356 and the coefficients friction using process fluid is in the range of 0.085 - 0.151. The calculated wear of the counter-body is in the range of (0.66/ 4.21)×10-3 mm3, asit depends on the friction conditions and the used multilayer coating.

In the present work Mg-Ga, Mg-Sn and Mg-In binary alloys with 1 and 3 wt.% Ga, Sn or In were studied in the as-cats state. Selected Mg-3Ga and Mg-3Sn binary alloys were subsequently extruded at 400 °C. Structures of investigated materials were studied using scanning electron microscopy and energy dispersive spectrometry. Mechanical properties were determined by Vickers hardness measurements and tensile and compressive testing. All materials were composed of primary magnesium dendrites and contained strong dendritic microsegregation. Both Ga and Sn have strengthening effect on magnesium; the effect of In is negligible. The extruded alloys were characterized by grain size in the range between 10-50 μm. Tensile yield strength and ultimate tensile strength of extruded alloys were clearly improved.

The presented article deals with the technology and principals of laser cutting. The article describes the properties of CO2 laser beam, input parameters of laser cutting process, assist gases, the interaction of the cut material and the stability of laser cutting. The chemical compositions of cut materials and their influence on the cutting properties focusing on the roughness of the surface, are described as well. In the experimental part the roughness of the surface was measured by using the 3D scanning and evaluation of the microstructure in the HAZ area was provided.

The field of material surface modification with aim of biomaterials construction involves several approaches based on surface treatments that allow to prepare materials, which support the cell adhesion and proliferation and thus aid and improve the tissue formation. Modified materials have a surface composition and morphology intended to interact with biological systems and cellular functions. Not only surface chemistry has an effect on material biological response, surface structures of different morphology can be constructed to guide a desirable biological outcome. Nano-patterned material surfaces have been tested with aim to determine how surface geometry, physical and chemical properties on a micro- and nano-scale can affect cellular response and influence cell adhesion and proliferation. Surface physico-chemical properties (e.g. chemistry, morphology, wettability, electrical conductivity, optical and mechanical properties) of treated surfaces were determined. The enhancement in cell adhesion and proliferation on modified substrates was studied in vitro. Bactericidal action of noble metal nano-particles (e.g. Au, Ag) on polymers was characterized. The influence of metal nano-particles grafting by using metal nano-particle suspension prepared by "green" methods was determined.

Dimensional changes, or distortion, play a very important role in carburizing. To keep carburizing process productive and profitable, it is crucial that the resulting distortion is minimized. The purpose of this experiment was to carry out low-pressure carburizing and measure dimensional changes, residual stresses, characterize the resulting microstructures, and determine hardness in the specimens. These are the most important clues to the quality of the carburized layer. Experimental materials were the most widely-used carburizing steels: C15, 16MnCr5 and 15NiCr13. Residual stresses in the surface were determined by X-ray stress measurement.

This paper aims to describe powder metallurgy methods of production Ni-Ti shape memory alloy - self-propagating high-temperature synthesis (SHS) and spark plasma sintering (SPS). There are compared microstructures and phase compositions of alloys produced by SHS and by a technology containing SHS, milling and SPS. At the same time there is determined the influence of the SPS sintering temperature on the structure of Ni-Ti alloy. Self-propagating high-temperature synthesis was initiated at 1100°C with process duration 20 minutes the heating rate of approx. 300 °C/min. The product is highly porous and contains undesirable Ti2Ni phase. The SPS technique allows to obtain product with low porosity. The disadvantages of SPS technique are growing amount of Ti2Ni phase and formation of other undesirable phases (Ni4Ti3 and Ni3Ti).

This research aims to solve the issues of limited measuring range and great accumulative error in the digital assembly of aircraft parts. In this paper, we propose the use of array visual measurement technology for the assembly of large aircraft parts. First, the visual measurement space for large aircraft parts assembly is determined. Second, the visual measurement model for large aircraft parts is constructed. Then, the differences that occur in real-time to the global coordinates can be calculated by using the pre-assembly feature points of large parts and the measurement tools of an array visual system. Finally, the real-time simulation of the aircraft assembly process is conducted in ADAMS by the secondary development of the software. In addition, errors between the real-time assembly and the design model are solved, and then transmitted to the mechanical actuators, which in turn adjust their attitude to complete the assembly of the large aircraft parts. The results show that array visual measurement technology for the assembly of large aircraft parts is feasible and efficient.

In order to enhance the stiffness of the gas film and increase the maximum speed of the rotor, this paper proposes an ultrasonic levitation structure with a cone type bidirectional supporting motor. The performance of the conical-type ultrasonic levitation support is analysed and tested according the relationship between the levitation force and levitation gap. Through theoretical analysis it is realised that the critical speed and vibration mode of the motor rotor is affected by the change of levitation gap in the ultrasonic levitation condition. The experiments with levitation gap and the maximum speed of the motor rotor show the structure can reduce the suspended gap, while simultaneously the maximum speed of the rotor is increased.

The article deals with the calculation of stiffness of a secondary suspension spring built in a bogie of a rail vehicle with a tilting car body. The vertical stiffness of the springs was calculated using the ANSYS program. The results were compared with calculated values afterwards. The lateral stiffness was evaluated in a similar manner. Analytical method by Gross, Wahl, Budrick, Timoshenko and Ponomarev was used for comparison with numerical values. The ANSYS simulation was performed for calculating the vertical stiffness of the triple springs. The most suitable analytical method is a method by Timoshenko and Ponomarev, where the percentage difference was the smallest. The obtained data will be used as an input for the design of coil springs which will be implemented in a model of a vehicle with a tilting car body, for which the comfort values during transition in curve will eventually be determined.

Nowadays, majority part of powder injection molding (PIM) market in Europe consists in automotive (43 %). In contrast, to medical applications only 13 % of market is devoted. This paper is focused on a new design and production technology of the adenoid cutting curette used in otorhinolaryngology. In the theoretical part, the present design issues of the cutting curette are shown, and time consumption and wear problems of sterilisation are described. Experimental part consists in selection of suitable metal powder for medical application, computer-aided engineering (CAE) Moldflow analysis of proper gating system followed by construction of injection mold and production of real samples. The new design of replaceable cutting edge is easily customized according to various shapes of patient oral cavity and for doctor's need.

Aluminium and silicon alloys are widely used in practice. But there is increasingly more emphasis placed on the research and development of these materials. The aim of this article is to analyse modified aluminium alloy AlSi7Mg0.3. The paper is focused on the effect of particular modifiers in AlSi7Mg0.3 alloys on built-up edge formation in machining. Four variants of castings (unmodified alloy and alloy modified by chemical elements - strontium, calcium and antimony) were used. All alloys were compared with non-modified alloy. There were moulded castings from each modified variant and the casting of non-modified alloy. It was casted using a gravity-die casting into a metal mould with a thermal insulation.

Galvanic plating of polymeric structural parts is widely used in many industrial branches, e.g. in automotive. Minor errors in their manufacturing process are responsible for presence of surface defects. These defects, especially in the case of visual and decorative parts, are unacceptable. This paper demonstrates the usage of optical and electron microscopy to reveal and solve common problems in industrial production. Different types of galvanic plating defects on injection molded parts made of ABS, PC/ABS and PA manifest themselves by different ways.

The article deals with the principles of fixtures design and their application at machining of armature DM 100, PN 25/40-RF. It is bulky component that is produced by casting technology. Surfaces near the hole of valve are hard machinable due to weld deposit. Considering elimination of clamping device weaknesses that could originate due to unsuitable design and production, it is advantageous to use a virtual model along with simulation and analysis in CAD/CAM system. Nowadays technologists have strong tools in their hands that increase efficiency of solution not only conventional, but also specific, problems. On the other hand, they have to know to solve some difficulties in their mind, such are, for example, the differences in specifications of coordinate systems used for virtual model in CAD/CAM system and coordinate systems used in real production. The problems can arise in case of cutting tool definition according to the tool-in-hand or tool-in-use systems. Based on theoretical know-how two fixtures were designed for manufacturing of two sets of surfaces that are normal each other, so after inovation manufacturing operations were realized in vertical and in horizontal position of workpiece axes. Using new approach, the production efficiency and production rate have increased twice and no failure product has been made.