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The paper analyses the influence of the feed motion speed vf on the value of measured geometric errors of the four-axis vertical machining centre CNC FV-580A with the FANUC 0IMB numerical control system. The tests were conducted with LSP 30 Compact laser interferometer (by Lasertex). Examples of modern, laser diagnostic systems of numerically controlled CNC machine tools were characterised in the article. Self-tracking laser interferometer LaserTRACER, diagnostic appliance LaserTRACER-MT, laser interferometer with XL80 with environmental parameters' measuring module XC80 and with heat sensors along with XR20-W calibrator were presented. Measurement results and their analysis were presented graphically in the form of diagrams and tables. The conclusion section comprises the discussion of the results, summary and deduction.

A production stroke has to be taken into regard also at using bonding methods. A limit in an area of the adhesive bonding technology is long hardening time which is needed for reaching a handling strength. Second solution is using quick hardened adhesives (cyanoacrylates). Second limit is a necessity to treat the adhesive bonded surface which is regarded in production companies as another cost and a problem in an area of a waste economy. The paper deals with the necessity to mechanically treat the adhesive bonded surface, that means an influence of links in the boundary of the adhesive bonded material and the adhesive. The aim of the research is to set the influence of the mechanical and chemical surface treatment of the steel surface at an application of cyanoacrylate adhesives on a strength of the adhesive bond.

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.

A research analyses an influence of an adhesive surface treatment on an adhesive bond strength. Constructional adhesives used for bonding in an automotive industry were used for the research. A significant factor for evaluating the adhesive bond failure is the research of bonded areas by means of an optical analysis. An even layer of the adhesive in the bond is connected with it. The adhesive bonds diagnostics is difficult. It is necessary to control a quality of the production at the production process. A significant factor lowering the resultant strength of the adhesive bond is its creation. One of possibilities of the adhesive bond diagnostics is to use a method of an optical analysis. An uneven layer of the adhesive belongs among main causes of a failure / considerable decrease of the strength of the adhesive bond.

Contribution presents new principles of inspection technology for examination of integrity of the gas pipelines material and its welded joints. Information is linked with real output from measuring on gas pipelines and results are compared to conventional NDT methods. Visual control is done as a first non-destructive test in 100% extent for all welds. It must be executed well in advance before all the other tests in order to remove superficial defects and irregularities, which could prevent correct application and evaluation of other tests. It is used to detect superficial defects and geometrical irregularities, especially cracks on the surface of weld or in the heat affected area, elevation of weld, undercuts in transitions to base material, defects in the root of weld, if it is accessible from pipe's inner side, including inadmissible offset of weld surfaces from pipe's outer side and their continuity of transition to the weld. The following are the tests to detect internal defects radiographically, respectively by an ultrasound and tests to detect superficial cracks for branches, necks and fillet welds.

Most of magnesium alloys are usually used for applications at ambient temperature. The significant decrease in mechanical properties is observed already at the temperatures higher than 150°C. This is the reason for the effort to prepare a new low-priced magnesium based alloys with improved mechanical properties at elevated temperatures, e.g. for components of combustion engines. The microstructure and mechanical properties of selected commercial magnesium alloys AZ31, EZ23, ZE41 and WE43 with relatively new MRI153 alloy for use at elevat-ed temperature were compared. Brinell hardness, yield strength and tensile strength at the temperatures of 20, 150 and 200°C were studied. It was found, that relatively low-priced MRI153 alloy appears to be very good alternative alloy for use at elevated temperatures.

The efficiency of the machining processes, the accuracy of the manufactured parts, and the quality of the machined surface are determined by several factors: the tool geometry, the parameters that affect the kinematic relations, and the cutting parameters. Therefore it is necessary to investigate the effect of each characteristic parameter on the technological parameters in the research of rotational turning. In this paper first we sum up the geometric and kinematic relations that affect the defining parameters of chip removal. We give an overview of the parameters which must be given in rotational turning. We briefly show the method used for the mathematic-analytic definition of these parameters. After that we determinate and analyse the alteration effect of the inclination angle on the resultant axial feed, on the theoretical arithmetic mean deviation and on the characteristic parameters of the chip cross-section.

The article describes mathematical model and possible usage of results of dynamic loading simulation of the chassis of track vehicle. The computational model is designed for computational simulating system MSC.ADAMS.AVT. Possibilities of research results usage are described in the article mainly. Results of simulation calculations were used for make-up of constructional parameters parts file of vehicle chassis and findings of influence their changes on changes of directional vehicle stability by running at first. Make - up of approximate relations for transaction of fast orientation calculations is second described possibility of results simulation calculations usage. The possibility of usage of results simulation to do verification of mathematical model is third possibility of usage results simulation calculations. The optimization of influence changes of several design value together is fourth possibility of usage of results simulation calculations that is described in this article.

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.

Some perspective materials are characterized by shape memory effect and NiTi alloy belongs to their main representatives. NiTi is an approximately equiatomic alloy of nickel and titanium and it possesses interesting properties, such as superelasticity, pseudoplasticity and good corrosion resistance. Hence, it is used in different branches of industry (aerospace, medicine, engineering etc.). Common manufacturing melting methods of this alloy are vacuum arc remelting (VAR) and vacuum induction melting (VIM) methods. However, these methods have some disadvantages. The VAR process must be repeated several times to achieve sufficient homogeneity of manufactured ingots. During the VIM process the melt can be contaminated by carbon originated from graphite crucible. Therefore, powder metallurgical methods have been extensively investigated in last years as an alternative to the common processes. In this work, NiTi samples were prepared by the thermale xplosion mode of self-propagating high-temperature synthesis (TE-SHS). Chemical and phase composition, as well as microstructure and hardness of the prepared samples were studied. Afterwards, the samples were heat treated and the influence of the annealing on the studied characteristics was investigated.

The article is focused on the analysis changes dependence on the temperature on the aluminium alloy with 10.1% Mg, 1.32% Si and 0.43% Mn by internal friction. Internal friction is a property of the material is measured on the ultrasonic resonant aparature at a frequency about f = 20470 Hz. The measured temperature range was from 50 °C up to 420 °C. Precisely measurement of the internal friction can be monitored ongoing structural changes and various mechanisms that prevent these changes.

This paper presents static measurements results of the kinematic pair centre of the C-rotary axis of the 5-axis machine tool at digitised angle positions αof the machine rotary table. The measurements were conducted with the application of R-test calibration and measuring system. The article discusses the test sequence as well as the evaluation of the kinematic centre location of the rotary axis, relative to linear X, Y-axis. The summary formulates guidelines covering the compensation of the axis location. Measurement results were presented in diagrams and tables.

Repairs of branch connections defects on high-pressure pipelines allied to gas-escape are nowadays difficult processes. The reason is necessity of performing sections of damaged pipeline that is connected with transport medium layoff or with using technology of by-pass installing around damaged part of pipeline. In article, a concept of technology of branch connections repairing by split pressure sleeve is presented, which is in recent times realised only at straight sections of pipelines. Concept consist of split sleeve design along with wall thickness optimization in simulation software ANSYS. Concept of internal space of sleeve sealing up from welding workspace using appropriate seals placed at its sealant carriers is presented, too. Dimensions, material of carriers and sealant location were designed according to experimental measure of temperature, together with subsequent validation of heat transfer by numerical simulation in software SYSWELD. Described repairing method concept seems to be an appropriate alternative of branch connection repairing that allows fast and safe correction with lowered operational costs on realisation of repair and possibility of speeding-up and simplifying emergency conditions solution.

Springback of v-type sheet metal must be controlled during the high precision forming process. While, variable blank-holder force technology is an effective measure to control sheet metal springback, but it only overall control the stampings. The project was put forward through the v-type sheet's variable blank-holder force and adjustable drawbead to control springback, which is place electric adjustable step drawbead around the blank-holder. Changing the blank-holder force, meanwhile, adjusting the height of the drawbead according to the needs of the stamping real time, so as to control the quality of sheet forming. To get the optimal combination of variable blank-holder force and adjustable drawbead, this rearch for the technology to control the springback, which has carried on the theoretical analysis and numerical simulation, then providing test for it.

The article describes a method of measuring engine oil wear metals by Atomic Absorption Spectrometry (AAS), which is an analytical method used to determine the concentrations of various elements in the sample. Atoms of different elements absorb different wavelengths of light in proportion to the quantities in which they are represented, as an analytical measurement property is performing absorption of radiation by free atoms of the reference element. AAS method with flame atomization allows measuring the concentration of about 60 elements of the periodic table in a solution with a sensitivity from hundredths to hundred μg.ml-1. It is used in the analysis of samples of different origins. This method makes up a significant part of monitoring low levels of toxic elements in environmental samples, which is very good to be used for its high sensitivity and selectivity. The aim of the study was the evaluation of the composition of wear particles tested oil samples by AAS, which is highly accurate and a fully automated tribotechnical diagnostics method. The intensity of each line radiation gives information about the content of investigated metals in the tested samples of motor oils, which enable us to identify not only the place from which abrasion arises, but also reveals the cause of the critical condition of the mechanism.

Zn-Mg alloys, in which Mg is an alloying element, are proposed for medical applications as a promising biodegradable material for temporary implants in orthopedics or traumatology. They can be used to replace nonfunctional or damaged tissues. When the healing process of tissues is finished, the Zn-Mg alloys are gradually decomposed in a human body and a reoperation is therefore unnecessary. Their mechanical properties must be similar to the characteristics of human bones. Large grains are typical for the structure of cast alloys. Pure Zn and Zn-0.8Mg alloy were cast and subsequently extruded at 300°C. The structure and mechanical properties (Vickers hardness, compressive and tensile strength tests) of the cast alloys were compared with those of the extruded alloys. Pure Zn and Zn-0.8Mg alloy after the extrusion had a fine-grained structure and showed better values of mechanical properties in comparison with the cast alloys.

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.

In this paper the technological process of bonded magnets manufacturing was described. The greatest dangers arising during the process steps that have a significant impact on magnetic, chemical and thermodynamic stability Nd-Fe-B bonded type of magnetic materials were also indicated. The effect of the biencapsulation of Nd12Fe77Co5B6 powder particles with Ni-P/epoxy resin, phosphate/epoxy resin and Cu/epoxy resin layers on the finale magnets has been evaluated. The production processes in technological terms in original and after improving modification were presented - the technological process taking into account the stage of powder surface etching and the powder particles biencapsulation. It was proved that the preliminary biencapsulation of particles surface before consolidation in some cases significantly improve the mechanical properties of the bonded with epoxy-resin magnets.

Quality of high-pressure castings is influenced by many factors. Structure and mechanical properties of these castings are mostly influenced by properties of casted material, technological parameters and thermal conditions in die casting mould. Thermal conditions in system casting - die casting mould is ensured by tempering system. However there is problem with thin cores and thin protrusions of die casting mould which is not possible to keep on the optimal temperature during casting by commonly available methods. Thus there is overheating in these places. It leads to the porosity of casting and also to the unsufficinet treatment of critical places of moulds which causes the lowering of their service time. With regard to the increasing requires on the castings quality is in practice searching still new possibilities how to cool down these critical places. One of the possibilities is to ally cooling by liquid CO2 into such places. This paper deals with the monitoring liquid CO2 cooling effect that is applied into the die casting mould core.

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.

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.

AISI 316Ti is Cr-Ni-Mo austenitic stainless steel stabilized by Ti, recommended for construction of various industrial and medicine devices. In spite of its high Pitting Equivalent Resistance Number (PREN=23.688) it underlies local corrosion namely pitting in aggressive chloride environment. Appearance and extent of AISI 316Ti corrosion damage in a particular chloride solution depends strongly on temperature and surface treatment. One part of tested specimens is surface untreated the second part is treated by nitric acid passivation. Specimens are immersed for 24 hours at the temperatures of 30, 50 and 80 °C in 0.3M FeCl3 solution to induce pitting. Pitting corrosion morphology (shape and size of corrosion pits) is observed viewed from above and in profile as well, by optical metallographic microscope and scanning electrone microscopy SEM. Shape and size of corrosion pits is compared in dependence on temperature and surface finish of specimens.

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.

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.

Grinding is the most common finishing process for components that require high accuracy and surface quality. Process performance depends on many factors related to process conditions, workpiece material, grinding fluid but grinding wheel is of special interest. Grinding wheel performance plays a major role on workpiece quality and process efficiency; preparation of the grinding tools and the creation of specific topography of the wheel surface is in direct relation to grinding wheel performance. Questions connected to the possibility to increase production efficiency of diamond dressers owing to technological changes of their production and simplification of preliminary selection of initial samples of diamond are considered. Furthermore, recommendations on improvement of the dressing process of abrasive wheels are made using 3D FEM simulations. The results of theoretical and experimental investigations which cover the development and research on electrochemical dressing of working surface of diamond grinding wheels with metal bonds are also provided.

Tribology is an important method for evaluating the coefficient of friction and wear of friction pairs of technical materials. The most commonly used modes are "pin on disc", resp. "ball on disc". Tribology can simulate the stress of two objects (the friction between the objects) under the real conditions. The output of the tribological test is a specific value of the coefficient of friction and wear rate. For a comprehensive evaluation of tribological properties is used the optical microscopy - to evaluate the size of wear of the pad (groove width) and of the pin (loss of material of the ball or roller). The use of modern sophisticated equipment allows to evaluate the coefficient of friction and wear also in various environments, such as in the process fluids.

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.

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.

Cutting shop-floor experience often shows that after machining one lot the insert is changed and the next lot is started with a new insert. Thus the tool life of the cutting tool is not fully used. Therefore we analysed how to determine, after machining a lot with a given number, the number of pieces of the next lot that can be machined with the same insert. Based on the cutting experiments we determined wear curves for some specific parts. With the introduction of two new definitions (equivalent number of pieces and equivalence ratio) we elaborated a method with which the machinable number of pieces of the next lot can be determined - even if a lot is machined by other cutting parameters - until the tool life criterion is reached. Based on this method and using nomograms or an algorithm the further machinable number of pieces can also be determined.

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.