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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.

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 essay aims to identify the composite motion and the cutting force between the grinding wheel and roller of the roll grinder. Based on the analysis of roll grinding mechanism, this essay further uses Newton's law which describes linear motion and Euler equation which describes rotation to build rolling components' Newton-Euler dynamics equation. Then the essay simplifies rolling components' virtual prototype, and uses the dynamic analysis function of ADAMS to do dynamics simulation analysis of rolling components. Finally, based on the formula to calculate grinding force, this essay testifies that calculated results are consistent with simulation results, thus providing reference data for optimization.

New requirements placed to products, and hence to materials from which they are produced resulted in widespread use of instruments of quality assurance. Depending on destination of the product, its manufacturing process is burdened with the need to implement quality assurance systems, recording and analysing data, and also a process of continuous improvement. The article presents the results of practical use of selected quality tools in iron foundry. In order to determine the level of incompatibility of manufactured products the analysis was carried out based on the use of Ishikawa diagram and Pareto-Lorenz method. The results of the above analysis were defined as a starting point to develop a dendrogram and to determine the variant solution to the problem using programming of decision-making process, there was also developed diagram of the manufacturing process of iron castings.

Internal friction reflects the ability of the material irreversibly dissipating mechanical energy oscillations. That means, the material of high internal friction ability is able to significantly reduce the vibration amplitude. Dispersion of mechanical energy in the material is just the one of the ways of energy transformation for example conversion of mechanical energy to heat energy. This article is focused on the analysis of the internal friction changes depending on the temperature. For experimental measurements was used AZ91 magnesium alloy. Measurements were performed at different excitation voltages. In experimental measurements was used only ultrasonic resonance method. This method is based on continuous excitation of oscillations of the test bar, and the entire apparatus vibrates at a frequency which is close to the resonance.

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.

Metalworking fluid (MWF) aerosols are generated continuously during conventional machining operations and can have a number of adverse health effects. Exposure to the aerosols has often been reported to cause acute respiratory difficulties including asthma, hypersensitive pneumonitis and lung cancer. Aerosol measurement data was conducted to identify the major determinants that may affect exposure to aerosol fractions during turning of a cylindrical work piece on an uncovered conventional lathe. The aerosol mass concentration was investigated as function of spindle speed, fluid flow rate and sampling position. Synthetic fluid, mixed at 5% concentration with water, was applied via nozzle centred above the work piece at a distance of 70 mm. The aerosol mass concentration was determined gravimetrically and particle size analysis was performed by optical method. The results show that aerosol mass concentration increases with increasing the fluid flow rate and decreases by increasing the spindle speed. Moreover, the particle size analysis detected that a high quantity of particles smaller than 0.2 mm is generated at higher spindle speeds.

Using cutting fluids often enables an increase of cutting tool life. A large amount of cutting fluids produced in the European Union exists on the market of Czech Republic. It is quite difficult for purchasers of cutting fluids to acquire reliable test data about the performance of the fluids in industrial conditions and choose the best cutting fluid, the use of which will guarantee the longest tool life. In this regard comparative tests of cutting fluids were conducted at the laboratory of the Department of Machining and Assembly of the Technical University of Liberec to determine the effect of cutting fluids from different producers (from England, Germany, Norway and Switzerland) on tool life in turning and milling.

The article is focused on the machinability classification of wood-based materials resulting from experimental work targeted on the wear procedure of cutting edge. These types of materials are not currently classified into groups of machinability. Two representatives of the materials - laminated chipboard (DTD-L) and medium density fibreboard (MDF) were tested in the project. The process of material classification from the view point of machinability is well processed in engineering materials contrary to materials from wood processing. Experimental measurements were based on the determination of the radial tool wear. Tested materials were included according to achieved results in the material groups and their relevant classes. One of the most important classification indicators was the index of kinetic machinability KV. Material DTD-L has been selected as a reference sample - standard as the material most often used in woodworking industry.

The paper deals with stress of forming dies in complex conditions of concrete processes during their service life. Possibilities of assessment and prediction of tool service life based on comparative analysis of dynamic fatigue and abrasive wear are presented. Classical solution of dynamic fatigue is complemented by analysis of the situation of cyclic contact of rotating instruments. In this case super-position of cyclic pressure effect dominates, as well as abrasion on the surface of the functional surfaces of the rotating forming tool. Specific in this case is the different speed in the contact line and also the dynamics of development of size, shape and localisation of the surface exposed to wear by cyclic compressive stress. The solution is demonstrated on examples of different forms of wear of forging and rolling tools. The results of a comprehensive predictive analysis can be applied at designing of technological chains of forming operations.

In each industrial entrepreneur organization around the globe a three dimensional objective well known under the abbreviation QCD (Quality, Costs, and Delivery) is examined, pursued, and evaluated on daily basis. The nowadays crucial philosophy pertaining to process improvement in terms of quality assurance and significant cost reduction is that: "The quality must be manufactured and not controlled up". In order to be successful on the market place it is necessary to orchestrate, implement and carry out an advanced production quality assurance system with appropriate tools of course accompanying with previously precisely organized prototype and pre-serial stages of production. The article deals with a proposal of adequate methodology and the experimental implementation of quality matrix into manufacturing process assurance in order to improve a quality level and the whole QCD.

The aim of the article is to present the necessity of completion of the test stand of brake components of railway vehicles with the equivalent railway operation load simulator for the research of the wheel wear on it. The other aim of presented research needs is to perform the analysis of the equivalent conicity as a parameter for the rail vehicles in operation ride properties prediction. The sub aims are the change of frame, wheel, braking forces load via SIMRAIL simulator program load collection performance.

Recycled aluminium alloys are made out of aluminium scrap (new or old) and workable aluminium garbage by recycling. Due to the increasing production of recycled aluminium cast alloys is necessary to ensure their strict metallurgical control. The mechanical properties and the microstructure character depends on the chemical composition; melt treatment conditions, solidification rate, casting process and the applied thermal treatment. The mechanical properties depend on the morphologies, type and distribution of Si, Cu, Mg and Fe-phases, on the grain size, DAS and porosity distribution. Improvement of mechanical properties and structure of Al-alloys can often significantly increase the using lifetime of a casting. Different elements are added to achieve the optimum casting and mechanical properties. Modification can be achieved by several methods as faster solidification, mould vibration, melt agitation in mushy state and melt inoculation by using chosen elements like Sr, Na, Sb etc. Present work is focused on study of the effect of Sr-modification on the structure and mechanical properties of recycled AlSi10Mg cast alloy. For study and identification of intermetallic phases' was utilized standard (HF), colour (MA) and deep etching (HCl) in order to reveal the three-dimensional morphology of the silicon particles and intermetallic phases. For element composition of the specimen was used X-ray (EDX) analysis. Finally, the effect of modification on silicon morphology and fracture surface was examined.

Paper deals with the analysis of aluminium alloy welded joints produced by disk laser. Naturally hardenable Al alloy type AW 7075, 2.5 mm in thickness was suggested as welded material. Welded joints were produced by use of disk laser type TruDisk 4002 with 1.03 μm wavelength and maximum power P = 2.0 kW. Welded joints were fabricated with different parameters. Laser power varied within interval from 1.6 to 1.7 kW and welding speed was invariable 30 mm/s. Welding was performed without the use of filler metal. Laser light cable in diameter Ø 400 μm (spot diameter Ø 748 μm) was used. Welding was performed with Ar shielding gas with 10 l/min flow rate. Also root protection was provided with an inert gas (Ar). The focal length was f = 200 mm. Laser beam was focused under the surface of welded material. Evaluation of fabricated welds was carried out by use of light microscopy, microhardness measurement across the boundary of welded joints and static tensile test.

The components with formed surfaces are being an important category of the machine parts. They are applied in the most of industrial branches. In order to produce such type of machine parts it is necessary to harmonise the contradictory requirements, e.g. the minimal production time, the required precision of dimensions and the surface quality. A relevant role is playing the chosen machining strategy specified for the above-mentioned demands, namely during the finishing operations. The most important evaluation criteria for selection of the concrete CAM-system are: the disposable machining strategies, visualisation level of the proposed process and recognition of the virtually machined surface. The term "machining strategy" represents the pre-defined (and in the CAM-system also the available) tool trajectories that are optimised for machining of the variable formed surfaces so that the work-piece could be machined most effectively. A projection and evaluation of the cutting trajectories is not a simple process. There are at disposal many professional articles, which started to be published after occurrence of the first software solutions created as a support of the NC-software development. A development of the new strategies, i.e. the projection and optimisation of the new methods for control of the tool movement on the machined surface, is a multidisciplinary area, which requires knowledge from the theory of machining, descriptive geometry, informatics and also mathematics. The standard machining applications are such strategies, for example, that are able to optimise the cutting conditions in order to achieve a constant loading of the tool and in this way they enable prolongation of the tool durability as well as improving of the manufactured surface quality. Another important area is also evaluation and comparison of the existing strategies because the proper choice of them can help to reduce the machining times and the tool wear-out due to a shortened length of the tool operational path. This fact has a relevant impact on the production efficiency. The main topic of this paper is a description of the quality analysis focused on a surface area, which was machined by means of the various milling strategies and at the same time there were monitored deviations of the machined surface in comparison to the original 3D-model of the free-form surface area. This matters is analysed in [1], [2], [3], [4].

Milling is one of the most universal operations in machining processes because it can remove the redundant part of material efficiently, and moreover, it can produce almost all kinds of contour surfaces with a high quality finish. Surface roughness plays an important role in determining the product quality since it strongly influences the performance of mechanical parts as well as production cost. Many types of cutting materials are used as tool materials in today's metalworking industry. Selecting the proper cutting tool material for a specific machining application can provide substantial advantages including increased productivity, improved quality and ultimately reduced costs. This article is aimed at determining the influence of different tool materials on surface roughness of AlMgSi aluminium alloy after side milling with using of the analysis of variance (ANOVA).

The paper deals with modelling and optimization of dynamic characteristics of a semiactive suspension of the working machine seat with a vibration absorber. The suspension is composed of a spring paralelly ordered with a semiactive damper controled by the sky-hook control algorithm. For the improvement of the dynamic characteritics of the semiactive suspension there is also analysed the effect of a vibration absorber. The dynamic characteritics of the suspensions are optimized by the multiobjective optimization, where besides the component respecting the effect of the effective accleration of the seat also the effect of the effective relative displacement between the seat and fhe floor of the working machine cabin is considered.

Introduction into problems - Rapid Prototyping (RP) presents the automatic production of physical parts using by additive manufacturing technology. The start techniques for Rapid Prototyping became available in the late 1980s and were used to produce models and prototype parts. Today they are used for a much wider range of applications and are even used to manufacture production-quality parts in relatively small numbers. Rapid Prototyping is widely used in the automotive, aerospace, medical, and consumer products industries. In this paper are presented selected experimental test of materials used in different Rapid Prototyping Technologies. Main part of the paper is oriented on presentation of materials test of Fused Deposition Technology realized by authors on Department of Manufacturing Technology of Faculty of Manufacturing Technology in Presov (Slovakia).

In production practice, it is important to know the machinability of new constructional materials. This is related to the selection of adequate cutting tools and machining conditions. One of such relatively new materials is Duplex Stainless Steel (DSS). Manufacturing machine parts of hard-to-machine material is very troublesome. It is still more difficult when high quality requirements are to be met. Duplex stainless steel is used in applications for very severe working conditions, e.g. for modern deep-well pump bodies for mining industry or the shafts of electric mixer motors in food industry. This paper discusses the effect of cutting conditions on the machinability of DSS. The advantages and disadvantages of various tool materials with regard to machining of DSS are highlighted. Problems associated with the machining of DSS as well as tool wear and the mechanisms responsible for tool failure are identified and discussed. However, the machinability of DSS is an area that needs to be studied more deeply to cut the production cost.

Magnesium and its alloys are considered as suitable biodegradable materials which can be gradually dissolved in organism without production of toxic compounds. The present study is oriented on new group of possible biodegradable materials based on Mg-LMM (Mg- low melting metals) alloys. Due to the limited information about the effect of Ga, Sn and In on mechanical and corrosion properties, structure studies, mechanical and corrosion testing were performed. Corrosion behaviour of materials was studied using measuring of weight changes, Mg ions release and also by EIS technique in SBF (simulated body fluid) that is close in composition with human plasma. The obtained results indicate positive effect of both Ga and Sn on tensile and compressive properties, compared to the almost neglectable effect of In. On the contrary, all materials were characterized by decreased corrosion resistances compared to pure Mg. Mainly structure conditions were responsible for observed differences in corrosion rates.

Metal foams belong thanks to their unique properties into the group of new and perspective materials. The paper deals with foundry procedures used for production of cast metal foams based on non-ferrous metals alloys. Individual procedures of production in lab and pilot conditions are described, which result in casting with certain structural regularity. Attention is paid also to the obtained microstructure of these cast materials and to evaluation of their properties. The experimental part summarises the existing research works in this area, including future possibilities of their use. Cast metal foams are not yet produced in Czech Republic on industrial scale.

The article deals with the influence of charge composition on the microstructure and mechanical properties of synthetic nodular cast irons after casting and after heat treatment (ferritizing annealing and isothermal heat treatment). The paper shows a comparison of the microstructure of nodular cast irons with the graded amount of steel scrap in a charge. The chemical composition of individual meltages was regulated alternatively by ferrosilicon (FeSi) and carburizer or metallurgical silicon carbide (SiC). The results of the experiments show that the SiC additive positively influences the microstructure as well as the mechanical properties of nodular cast iron, especially in specimens from the meltages with a higher ratio of steel scrap in the charge. Moreover, the production of synthetic nodular cast irons with a SiC additive is economically advantageous.

In both the engineering and the agricultural industries, components that are no longer considered entirely fit for purpose are already being exchanged for new parts that have a longer operating life. Today's fast developing industrial sectors are making higher demands on standards for the quality of their components. Such components and their lifetimes are very closely linked to the discovery of new materials which will better meet the requirements of the individual industries. This paper describes the experimental assessment of special castings from the viewpoint of their durability in the face of abrasive wear and friction, density, hardness and their metallurgical structure. In laboratory tests, ten experimental samples were prepared containing increasing amounts of carbon and chromium, whilst the other chemical elements remained constant. Durability in the face of abrasive wear was evaluated on grinding plates with various sizes of abrasive parts. Hardness was determined according to the Vickers method. The results of the experiments confirm the hypothesis of a proportionate increase in resistance to abrasive wear with the increase in carbon and chromium.

The paper presents application of Siemens RobotExpert software of industrial robot offline programming. The deburring process of aluminium wheel is described and developed. The robotic work-cell contains robot ABB IRB 1600id and two axes positioner ABB IRBP A 750 D 1000 H 700. The final robot tool path is checked using the collision viewer, the joint status monitor, the tool centre point speed viewer and tracker.

Objectives of the paper are intended to implement system solutions to nondestructive evaluation of technologies associated with verification of equipment, preparation of samples with different types of functional properties and their subsequent evaluation of various scientific methods. The main objective of experiments is to transform new knowledge of non-destructive technologies into industrial practice in the evaluation of functional properties of the surface and subsurface layers of these technologies. The aim is to increase the level of cooperation R & D institutions with social and economic practices through knowledge and technology transfer, and thus contribute to increased economic growth of the regions in Slovakia. This work is related to the project with the University of Zilina OPVaV-2009/2.2/04-SORO number (26220220101). Its name is Intelligent System for Nondestructive Technologies to evaluation of functional properties of parts of X-ray-diffractometry. The main objective of the project is to transform new nondestructive technology for knowledge transfer to industry for evaluation of functional parts in surface and subsurface layers of non-destructive techniques.

In this paper, we deal with the topic of production of precise wax patterns for investment casting technology. We focus on the issue of scanning thermal image arrays when measured object (wax blade model) has a temperature very close to ambient temperature. It is shown on specific examples how to filter disruptive thermal reflections that enter thermal array scanning on almost perfectly reflexive body. Based on verification of this measurement using the touch probe thermometer, this paper deals with the thermal influence of wax models in various stages of production. The biggest influence on stability of wax models occurred on workplace that carries out bonding of wax models into trees, where they use heat source for bonding, which in a moment can affect the temperature of the wax model so that its temperature is above the critical 30°C. The possibility of shielding of radiant heat, which significantly affects the shape of the wax model is also pointed out in this paper.

Machinery maintenance significantly participates in its reliable, serviceable and safe operation. Well-timed maintenance can identify a fault condition of machinery leading to manufacturing a product of poor quality. Maintenance interval can be fixed or maintenance can be done when needed, meaning at the moment when some of operating parameters get worse. An example of determination of diagnostics interval set based on machinery vibrodiagnostic measurement is described in the paper. The shown steps are universal and can be applied to another technical diagnostics methods as for example tribodiagnostics, thermodiagnostics, non-destructive materiology etc.. This way economic savings can be reached better comparing to maintenance done in fixed planned dates.

In paper are presented basic characteristics and problems in area of Rapid Prototyping technology with use of layered production technology named Fused Deposition Modelling (FDM). It is progressive method of 3D model product creation based on geometry obtained from CAD system with application in different industrial areas. Text of the paper is focused on optimization of Rapid Prototyping preparation process. There also is algorithm that leads to selection of suitable setting conditions. Utilization of algorithm is explained on case of printing with use of UPrint device and Catalyst software. There are outputs in form of graph and tables accumulating information directly affecting economical and quality aspects of Rapid Prototyping production technology.

This article provides perspective into creation of virtual 3D models of manufacturing devices and optimization of existing machine tools by using an alternative scanning device and freeware software applications (open source elements). This alternative offers scans of components surfaces that are from the viewpoint of precision and quality comparable with much more expensive devices. Various parts of the paper describe the process of creation of the environment with the use of Kinect scanner device and various software tools. At the end an additional options are provided for using with sensing device.