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Nowadays the pressure to increase the efficiency of the machining processes is constantly growing. The efficiency of the machining process can be pursued from two basic perspectives - enhancing the cost-effectiveness of the process (decreasing production costs) or increasing production in time. Via these approaches alone, manufacturers of parts as well as suppliers of machine tools and cutting tools try to improve their position in a highly competitive market. One of the approaches to increase efficiency is the correct choice and subsequent optimal exploitation of the potential of cutting tools and machine tools as well as a reduction in the energy intensity of the cutting processes for a given component. That is what led to the idea of creating an analytical-material model for determining the force interaction between the cutting tool and workpiece, energy intensity and machining process efficiency. The result will be an application that helps technologists in practice to choose correctly the appropriate types of cutting tools, operations, machine tools and also quickly determine the main parameters of the cutting process so that there is the possibility of comparing their results with other variants. The first step and goal is to create an overview of the cutting processes and the associated cutting process modelling, compare their advantages and disadvantages, and then propose an approach of our own.

The aim of this paper is to identify the causes of defects in rolled brass sheets which appear in the final stage of the blank production. These defects cause the increase in the production cost of the blank, which is undesirable. The analysis methods were used, such as spectroscopic chemical analysis, microstructural analysis using light and electron microscopy and the application of selected mechanical tests. Based on the analysis results, the analysis and cause determining and type of qualification occurring defects was realized.

The requirements for reducing the weight and increasing the strength and carrying capacity of the plane and space structures are constantly growing. The one of the way how to meet demands is to use the layered shell composite structures. They could be applied not only in mechanical engineering (containers, pressure vessels, etc.) but also in the civil engineering (cooling towers, roofs, etc.). The article deals with computation procedure of shell and plates using meshless methods. A mesh-free local Petrov-Galerkin (MLPG) method is applied to solve laminate plate problems described by the Reissner-Mindlin theory. Two projection methods are developed to generate the shell surface using the Lagrangian mesh-free interpolations. The bending moment and the shear force expressions are obtained by integration through the laminated plate for the considered constitutive equations in each lamina. The Reissner-Mindlin theory reduces the original three-dimensional (3-D) thick plate problem to a two-dimensional (2-D) problem. Results of transient dynamic loads in the composite plates using MLPG solution are presented here.

In addressing the motion of machine parts, machines and equipment it is necessary to first create a kinematic model. Kinematic model of a device schematically captures all its properties which are essential in kinematic analysis. This article deals with kinematic analysis of a simple mechanism executing a rotational movement. We analyzed the movement of its end points. Numerical solution was implemented by classical kinematics using different coordinate systems, while model mechanism has been also modeled and solved in the program MSC Adams. The result of the computer simulation is designation of the searched kinematic parameters and the other required parameters of the solved model. Solutions are time kinematic variables over time, which are shown graphically.

The theory of self-excited vibrations (chatter) in machining, formulated in the 1950s, assumes a single cutting force. The assumption of a single cutting force in unstable cutting is commonly accepted to this day. In this paper, we will present the reader and listener with a hypothesis concerning the effect of several dynamic forces acting on unstable cutting during turning operations. A new form of the force model will be presented. The calculation of stability limit as well as accuracy of the prediction of stable cutting conditions depends on this model. The validity of the hypothesis has yet to be demonstrated. Preparations for verification experiments have been under way for approximately one year and the experiments will start this year (2014). The hypothesis is based on the results of some earlier measurements of the dynamic forces by foreign authors as well as one of the authors of this paper, Miloš Poláček.

This paper describes a method of ABS-aramid composite material production by Fused Deposition Modeling Rapid Prototyping System. In the beginning there is presented common technology of parts production by Fused Deposition Modeling method of Rapid Prototyping. Then it deals with the theoretical description of proposed concept production of ABS-aramid composite material by Fused Deposition Modeling method. In the main part it describes an experimental testing of proposed concept at the Faculty of Manufacturing Technologies in Presov in the laboratory of Rapid Prototyping. For creation of sample bodies using the FDM method of RP we used the combination of basic ABS material reinforced by aramid tissue. At the end it summarizes possible trends of further development and research in described area together with possibilities of industrial applications.

Accurate and effectively machining of steel class AISI is in the fact of its chemical composition and mechanical properties often a significant problem. Effort to preserve the economical efficiency of whole production process is necessary to have behavior of the cutting tools in the process of machining these steels. Food industries all over the world use this type of steel as a basic construction material of machines and equipments designed for this type of industry. Ability to consistently know these steels is the way how to effectively machining. Small and medium manufacturing enterprises not have the means to experiment with this material and wasted, because it belongs to more expensive. For this reason in order to create high-quality machined surface while minimizing defects of products in production is significantly increased time of machining and producing product from this steel is economically inefficient. Paper deals with study of surface quality after machining of steel AISI 304. Outputs of realized experiment should help to small and medium companies to improve knowledge of steel AISI and its machining and also better understand how to effectively and profitably produce products of these steels.

It is necessary to study and master the springback rule of single point incremental forming of magnesium alloy on different process parameters, which has important theoretical and practical application value to complement and perfect the springback control technology of single point incremental forming of magnesium alloy. Taken the variable angle truncated cone as the research object, used the ANSYS/LS-DYNA as research tool, viewed the springback amount as research criteria, the influence of different process parameters to the springback of single point incremental forming is studied in this paper, which includes forming temperature, friction conditions and tool diameter. The results show that the springback could be effectively controlled when the forming temperature is 250℃, the static friction coefficient is 0.2, the coefficient of kinetic friction is 0.1 and the diameter of the tool is between 10mm and 12mm.

The paper describes the surface roughness measurement of functional parts of tools for minting coins. The coining dies were coated with three types of coatings - CrN, TiCrN and WC/C. Roughness of the coining die surface is a very important factor for the quality of a struck coin. The quality of specific coatings on the coining die surface was evaluated by a contact (Hommel Tester T500 roughness measurement device) and contactless method (microscope Sensofar PLu neox) by using optical interferometry and confocal microscopy. Results from the shop measurement gained by using the roughness measurement device were compared to the laboratory measurements gained by using microscope. Moreover, results were illustrated in the graph. Measured values were identical. Only the CrN coating showed bigger difference. Minimum roughness value was measured on the coining die with the TiCrN coating. The WC/C coating reached the maximum roughness value. 3D visualization method of surface roughness using software Gwyddion proved inappropriate for burnished surfaces.

This article deals with the non-destructive ultrasonic testing of split sleeve butt joints by ultrasonic methods. Split sleeve is used to repair gas pipelines with gas leakage. The new ultrasonic methods TOFD and Phased Arrays are compared considering to the selected butt weld configuration. To compare testing methods, ES Beam Tool software was used to prediction of ultrasonic beam spread through weld joint. TOFD technology was selected to butt weld section testing according to the beam spread simulation results. The results of ultrasonic testing by TOFD method were compared with results of macrostructural analysis of weld joint. Controlling the suitability of testing method to planar defect identification, the artificial defects were prepared and tested. The appropriate setting of measuring technique can be predicted from experimental results.

The paper deals with the practical use of matrix model of sustainable development, the MSD (Matrix of Sustainable Development) in Industrial Management and an introduction to possible problems in implementation. The method is based on expert evaluation, the output of the relational matrix are values of importance, resp. the overview of the priorities of the problem, i.e. the individual social requirements and the factors of quality products. The implementation of the MSD model contributes to the holistic understanding of the product's life cycle. The results reveal the model on the one hand in it is the real importance, and, on the other hand, the possible shortcomings of some hitherto unknown factors. The benefit is also involved in research in the field of quality management and a focus on customer requirements.

The article focuses on the issue of 3D measuring surface parameters using optical measuring devices, designing a statistical experiment and following evaluation. The development non-contact surface texture measurement methods lead to new possibilities for describing the surface of machine parts. But cannot be to rely only on the obtained the measured parameters values, and it is true that it is necessary to prepare the measurement. The processes of measurement enter many influences. Some of these effects can manage it, and then we call those factors. At the output of the receive process feedback. Method DOE (Design of Experiments) is used to locate a combination of factors that provide the most favorable response. The proposal described experiment compares and evaluates various surface roughness parameters of two different materials and machining technologies samples. Measurements were done by two operators, and each measurement was carried out three times. Measurement took place on a confocal laser microscope LEXT OLS 3000.

The article describes the fundamental physical principles of the ultrasonic defectoscopy TOFD (Time of Flight Diffraction) and Phased Array. There is a report from the ultrasonic testing of girth welded joint with ultrasonic flaw detector OmniScan MX2 16:64 PA from the company Olympus NDT. In welded joint were artificaly made three defetcts. Two lack of sidewall fusion (on the left and right side of welded joint) and one crack in axis of welded joint. Both ultrasonic testing were designed in software ESBeamTool 5 from the company Eclipse Scientific, which simulates the geometrical ultrasonic beams spread. At the end, data from both ultrasonic testing were evaluated. The same procedure will be used for the design of ultrasonic inspection TOFD and Phased Array at girth welded joints of gas pipelines.

An experimental and analytical study on the effect of asymmetry on vertical dynamic response of railway vehicles has been conducted. The experimental study featured a typical vehicle model of laboratory scale and a real railway vehicle wagon. The experiment was used to gain insight into the effect of asymmetry on vertical dynamic response and to validate an analytical model of the vehicle-track interaction. This paper presents the results from the study and shows that mechanical asymmetry changes the behaviors of the system. The current contribution introduces a methodology of analytical solution of vertical dynamic response of the railway vehicle. Moreover, a mathematical model according to the physical system considered was developed under MATLAB environment.

This paper deals with analysis of surface integrity of steel after electro discharge machining (EDM), water jet machining, (WJM) laser beam machining (LBM) and plasma beam machining (PBM). The paper discusses surface integrity expressed in surface roughness, sample precision expressed in perpendicularity deviation as well as stress state. This study also demonstrates influence of the various non conventional methods on structure transformations and reports about sensitivity of the different non conventional methods of machining with regard to variable thickness of machined samples.

The quantitative and qualitative results of the technological process are mostly determined by the level of finishing operations, which include particularly the grinding. It is characterized by high precision, the accuracy of geometric shape and generally a very good quality of surface. One of the factors to achieve the desired quality of the finished surfaces is in particular the knowledge of the effect of temperature of the contact surface of the grinding wheel and the ground piece. The article specifies the methodology of quantification of the impact of cutting parameters on the temperature of the grinding. Another requirement is the proper choice of other cutting parameters to guarantee the achievement of the required accuracy of dimensions and shape, increased performance and reduction of the contact temperature between the ground surface and the grinding wheel.

This paper proposes a concept model for product life cycle to present the characteristics of material flow, energy flow and waste flow in a manufacture system. Furthermore, two energy consumption calculation methods are provided according to the different components of the manufacture system, one is e-p method based on the processes of the system, and the other is e-f/s method based on the functions and statuses of the system. Then a carbon footprint calculation method is proposed on the basis of the characteristics of material flow, energy flow and waste flow in a manufacture system, and the energy consumption calculation above. Input-output analysis is carried out to establish the carbon emission calculation information table.

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.

Internal damping is able to monitor the microstructural changes in solid materials and these changes can be based onvarious mechanisms. In this investigation a same heat treatment was carried out on AZ31 and AZ91 magnesium alloys, aimed at detection of microstructure changes of material after homogenization annealing and also the process of precipitation was continuously analyzed by the internal damping measurement. Internal damping was measured as a function of temperature in AZ31 and AZ91 magnesium alloys by ultrasonic resonance spectroscopy. The internal damping spectrum was measured in the temperature range from 50 °C up-to 390 °C. Peaks of internal damping occurred in temperature range from 250 °C up-to 350 °C on AZ91 magnesium alloy. Also the mictrostructure analysis was carried out at the diferent stages of the internal damping measurement which showed creation of continuous precipitate in the maximum of the internal damping peak. The creation of the peak is caused by absorbation of energy by the process of continuous precipate nucleation and growth in the volume of material grains.

In most cases, the use of cutting fluids increases machining productivity while cutting different types of materials. Anti-adhesion ability is one of the main properties of cutting fluids increasing the tool life. Companies producing cutting fluids need to acquire information on anti-adhesion abilities of the cutting fluids as well as on anti-adhesion abilities of individual substances and effects for future development of their products. Consequently, methodology for evaluating anti-adhesion ability of cutting fluids was designed. The substance of the method consists in the evaluation of differences in the size of the wear area created under otherwise identical cutting conditions while using different cutting fluids at the front surface of the cutting tool where adhesive wear occurs during the cutting process under certain cutting conditions. The methodology was verified using 11 process fluids.

Owing to the evolution an adhesive bonding technology can be a complement of the classical methods as well as their compensation in the area of the bonding materials. Although the adhesive bonding technology has many advantages there are also some limits that contain an adhesive degradation which leads to the lowering of a strength function. In this study specimens were prepared with methyl-methacrylate adhesive (MMA) (Novatit - adhesive) and steel sheets, and the effect of degradation conditions at the room temperature on the adhesive bond strength was studied. Part of the specimens was exposed to a dehydration after the degradation time. The results showed that the degradation conditions and also the dehydration have considerable effect on the ultimate strength as well as on the durability of the adhesive bond.

Paper deals with the machining of super-hard ceramics by turning. The introductory part deals with analysis of used ceramic materials and their use in technical practice. Since it is a very hard technical ceramics and particularly resistant material, at present, is increasingly used to produce components that ensure long life and particularly high resistance, even in aggressive environments where metal materials can no longer be used. Products from ceramics are pressed and sintered directly to the desired shape, but in some cases they have to be machined, which technically can cause a problem. The aim of the experimental part is selection of suitable cutting insert, determining of cutting conditions that would ensure the productive machining of given ceramics. Work may serves as a troubleshooting support for machining ceramics.

The paper informs readers about the latest trends in ecological production of cores for the most demanding castings made of aluminum alloys on example of cylinder heads for combustion engines of the passenger cars. Although the cores bonded with silicates are known since the 60th years of the 20th century, only in recent years the technical progress has undergone such level that the leading producers of cylinder heads are able to deploy the system in serial production. Nemak started solving inorganic systems 12 years ago and today it delivers selected products to its customers and during their production there are cores being used which are joined by ecologic systems. The contribution analyses limiting technical aspects at application of inorganic systems. They replace systems of cold-box and hot/warm-box and it presents in details the benefits of ecological solutions which may be found in final product features. At the same time, it also points at difficulties which are still necessary to be solved.

A material usage of waste rubber powder in the polymeric composites increases their significance. Material recycling is very important ways of dealing with waste. The paper deals with laboratory tests of polymeric particle composites based on the waste - rubber powder which was gained as one of outputs of a recycling line. The paper describes mechanical properties of these composite systems such as: hardness (Shore D, Brinell), tensile strength (cohesive strength of filled epoxy resins) and it is also focused on the lap-shear tensile strength in the boundary adherend. Adding waste rubber powder into the epoxy resins and into other plastics materials and adhesives is a way for the material recycling which is inexpensive and sensitive to the environment. The inclusion of filler lead to the fall of lap-shear tensile strength values with an increasing amount of filler and to stabilizing on the level 5-20 vol.% filler in the epoxy matrix.

Multi-dimensional analysis does not include the conventional statistical techniques used in the operating reliability of the machine, where it is much more appropriate than the one-dimensional analytical method. The article deals with monitoring the wear particles in the tractor Zetor 8641 Forterra to pherograph creating pherographical footprint, in which the engine is in critical condition. The experimental part focuses on the trend curve fitting wear evaluated from individual particle analysis tests conducted to permit the monitoring of internal combustion engines (especially diesel). Theoretical assumptions about the relationships between selected parameters of motor oils and knowledge of individual material components allow to reliably determine the accrued failure due to the increase of wear metals in the oil and signal the increased engine wear in a timely manner and to draw attention to the approaching critical condition of the machine. By applying multi-dimensional statistical data in the measurement of wear metals enabled uncovering the links and structure of the tribodiagnostic parameters and sampling the oil, which also helps to determine deeper conclusions depending on the material identification impurities.

The soil is a considerable abrasive medium which exerts on tools processing the soil in a negative way. The main problem connected with using the soil processing machines is their wear owing to particles embedded in the soil. The ploughshare is one of the most loaded parts of the ploughing body and huge requirements are put on it. The aim of the research is to set an angle of a soil flow and connected wear of the ploughshare at the traditional processing of the soil. It is possible to further issue from ascertained pieces of knowledge at a production/renovation of the ploughshares with new functional surface. The statistical analysis evidenced that the angle of the soil flow on the ploughshare surface was the same with the angle of the ploughshare head. It followed from the measurements that the optimum angle for depositing the oblique overlay which is necessary for the creation of the serrated edge is in the interval 35 ± 4°.

In Al-Si alloys iron as an impurity causes decreasing of mechanical and foundry properties of castings. Nowadays is paid attention to adding different elements into aluminium alloys to increase the properties of final castings. Some elements eliminates iron by changing iron intermetallic phase morphology, decreasing its extent and by improving alloy properties. Also there is a possibility of using lower amounts of more elements, what can lead to change of morphology and to improve casting properties at the same time. The contribution is devoted to vanadium and combined vanadium and chromium impact to AlSi10MgMn alloy with high iron level. This effect is evaluated through microstructural analysis using different etchants. Colour metallography is also used to find the better and faster identification of the intermetallic phases.

Flake graphite cast irons are very used construction materials, which are characterized by good sliding and damping properties. Graphite and character matrix affects the properties of cast iron. It is also important to the size distribution of the graphite. Compressive strength graphite cast iron with lamellar graphite is very good , is 3 to 4 times greater than the tensile strength. The various types of cast iron with lamellar graphite is possible only in the tensile strength. Flake graphite cast iron are widely used in mass production where they use their good casting properties. With sophisticated sand moulds can produce a very complex shape castings with excellent mechanical properties and relatively low production costs. For this reason, cast iron with lamellar graphite are constantly used in the automotive industry for blocks, heads, engines, brake drums and discs, insertion loss cylinders, piston rings. At our department of Engineering Technology, Technical university of Liberec (Czech Republic - Europe) has long been focused on prediction methods of production quality castings for the automotive industry.

This paper is a part of the more detail research focused on the specific problems during grinding of bearing rings of diameters in the range of 600 up to 1000 mm. The paper discusses the specific aspects of surface burn after grinding associated with insufficient coolant feeding as well as the variable grinding conditions. Measurements are based on micromagnetic evaluation of ground surfaces due to large diameter of inspected rings and very fast response of the proposed technique. Magnetic inspection of parts is based of physical phenomenon originating from irreversible Bloch Wall motion well known as Barkhausen noise. Some experiments were conducted in the laboratory of our department (grinding of ring of small diameters) and specific measurements were carried out in the practice (rings of large diameters). This paper also discusses alteration of surface microhardness of ground surface as well as structure transformations.

There are many situations when you need information about the internal structure of the materials. Computed Tomography (CT) is a non-destructive method of evaluating the internal structure, which was originally used for medical examination of the human body. Today it is already used in many different fields, where the aim is the examination of the internal structure of the material. Geopolymer is a term for all inorganic polymeric materials which are prepared from alumino-silicate materials by geopolymerization in alkaline environment at normal temperature and pressure. Computed tomography (CT) is an advanced method that allows the study of the structure based geopolymer composites with short fibers or nanoparticulate reinforcement.