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With the development of the automotive and aerospace industry and also biomedicine, exotic alloys are more and more used from all machined materials, especially titanium and nickel alloys, but which are hard-machined materials. Therefore it is necessary to know their behavior when machining, thoroughly. Processes occurring in the cutting zone when machining, are so complicated and dynamic, that their definition is carried out by certain specified models. Because the models have errors and deviations, it is needed to improve their observation so, that these deviations will manifest minimally or not. Based on the scientific research of the cutting zone, the multifunction measuring system was designed, which allows simultaneous measuring of components force of cutting, heat distribution and deformation processes in cutting zone during machining without its interruption.

The main aim is testing the basic properties of cobalt super alloys, under its own brand name HAYNES, marking No. 188, at machining and propose the most suitable cutting materials and machining parameters. The superalloys are developed for elevation of temperature service where relatively severe mechanical stressing is encountered and high surface stability is frequently required. The cobalt-based alloys have been in use for several decades in the manufacturing of various components. Although technology development rises in chipless machining such as moulding, precision casting and other manufacturing methods, the machining is still number one, at piece production which is typical for energy and chemical engineering. The driving force for their development still has been requirement of higher operating temperatures for many manufacturing fields in industry area.

Technical literature presents numerous experiments with rotary turning tools application. Their advantages include extremely high durability, better quality of the machined surface as well as good chip shaping. Their wider industrial utilization was prevented due to the fact that a bearing is extremely dynamically stressed by a cutting force. Antifriction bearings have to big sizes and cause oscillation in the system, while sliding bearings manifested short durability and slackness inside. The authors of the paper tried to solve the mentioned problem by the application of an adjustable tapered roller bearing, ensuring a stable machining process. The paper contains the design as well as the results of the experimental verification obtained by the application of this improved tool.

Each construction of cutting machine tool activates geometric inaccuracies of the workpieces as a result of different stiffness of its joints. The acting of cutting force and the moving of its position leads to the deformation of the elastic joints of cutting machine tool and the elastic deformation of the workpiece appears. The aim is to maintain geometric modifications of the workpiece in required tolerances. The paper tries to identify these inaccuracies for case of a centre lathe.

To understand the process of chip creation during machining requires knowing the behaviour of metal at high degrees of mechanical and thermal stress which occurs in microvolumes of machined material. During machining the chip is characterized by unique deformation structure which does not occur with other methods of mechanical metal machining. This is the reason why its explanation is rather complex. The implementation of the knowledge of metal physics in confrontation with the experiment can finally contribute to the optimization of the process of metal machining and the selection of optimal cutting conditions.

The article deals with the basic steps of injection mould design. The goal of the research was the proposition of the mould form so to be achieved the minimum waste and the shortest time of both mould filling and product cooling. Studied mould component is intended to serve as a stopper in the automotive spotlight. The simulations were realized for three designed types of running system and for four versions of cooling system. Due to the design optimization, the pressures, originated inside the cooling system and inside the mould cavity during the injection moulding process, were also investigated. 3D model of the mould was created in Autodesk Inventor Professional software and then solidification of material was simulated in Autodesk Moldflow. On the basis of the best solution, real form was manufactured and placed into injection moulding machine Arburg Allrounder 320 C.

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

It is well known that the susceptibility of steels to hydrogen embrittlement is markedly dependent on hydrogenation conditions of samples. In this contribution are presented key results of relatively extensive studies oriented to examination of the effect of electrolytic hydrogen charging conditions (charging time and current density) on the hydrogen embrittlement of steels evaluated by the slow three point bend tests, micro- and macro-hardness tests. Various kinds of industrially produced hot rolled steel strips were tested (structural steel, dual phase and HSLA steels). The major aim of this study was to determine the hydrogenation conditions that do not result in the formation of defects such as microcrack or voids (in terms of absence of defects found by using optical microscopy) during hydrogen charging process.

Different types of aluminium systems are popular in building industry. Manufacturing technology of such products is a very important factor influencing the final result of production and hence the cost of production. Good quality of these systems results in good quality of investment where they are used. There is big competition on aluminium system market. The product competition decides about the existence of the manufacturer on the market. Therefore, it was decided to use the 3x3 matrix to evaluation manufacturing technology of aluminium systems produced by chosen Polish company for building industry. This matrix can be easily used to evaluate the technology of any aluminium products. From the analysis presented in the paper it results that the research company is located in area 9 of the 3x3 matrix, i.e. "Search for occasions", and the factors which decided about this position were evaluated by staff at the medium level.

The influence of the dynamic behaviour of the machine tool/workpiece system on the surface accuracy plays an important role in finish machining. In particular, the machine tool/workpiece dynamics determines the topography of the machined surface, which is crucial in determining the quality and performance of a mechanical part. A model to predict the dynamic effects of the cutting process in turning, as part of a machining simulation framework, is presented in this paper. Thermally, kinematically and dynamically induced errors can be easily implemented into the proposed model. Finally, several examples of the use of this model under different turning conditions are presented and compared to typical machined surfaces. The proposed model can effectively compute the roughness, form and dimensional accuracy of a turned surface.

The article deals with application of knowledge from lubrication of healthy spherical joints into hip joint endoprosthesis. As the observed most important physical parameter it was selected the coefficient of friction responsible directly for lifetime of the endoprosthesis. The article describes as well as experimentally verifies the idea of additional lubrication of hip joint endoprosthesis.

Modification alloy is an important part of the metallurgical process, and this also applies, of course, for aluminum alloys, particularly for Al-Si (silumins). As a modification of the material we can use the modification using the selected element or heat treatment of alloys, or a combination of both processes. One of the elements that it is possible to modify the alloy of Al-Si used is antimony (Sb). The paper examines the possible effect of the modification that element and heat treatment on the final tool wear after machining of the alloy AlSi9CuMnNi. In the experiments were made three castings from the alloy AlSi9CuMnNi without modification, three castings with the modification and without heat treatment, three castings with modification and without heat treatment, and three castings with modification and heat treatment too. These all castings were machining by turning with the same cutting conditions and next the tool wear of using inserts was analyzed. The described experiments and analysis are part of extensive research, focusing on a Faculty of Production Technology and Management, J. E. Purkyne University in Usti nad Labem.

Metal-plastic parts with steel inserts prepared by overmolding technique showed several molding defects including sink marks. The depths of sink marks on overmolding metal-plastic parts prepared at two injection overmolding temperatures of 280 and 230 °C and the same packing pressure of 60 MPa were measured by contact profilometer. They reached the depths of 3.02 mm and 1.51 mm at the overmolding temperature of 280 and 230 °C respectively. These values were correlated with sink marks indexes simulated in Moldflow software at the same conditions. Based on the simulated and measured results the optimal process parameters with injection temperature of 200 °C and packing pressure of 25 MPa were proposed. Simulation showed a positive effect of optimized parameters on sink marks minimizations. Sink marks indexes decreased of 20 % and 53 % compared to injection molding temperatures of 230 and 280 °C respectively. Maximal depth of sinks marks decreased to the value of 1.00 mm at optimized injection overmolding process parameters.

Evaluation of cutting tool wear is the technique generally used when monitoring cutting tool life. Different tool wear types increase depending on the cutting conditions and machined material on the cutting edge surface. The evaluated parameters depend on the tool wear type and where the tool wear is created. All these parameters are described by ISO 3685 standards. When a standard optical microscope is used, it is very difficult to determine the volumetric parameters and, in many cases, the actual (real) area of the tool wear. A standard optical microscope works on the basis of 2D screening. The new microscope works on the basis of 3D scanning, so the user has full information about the surface. This article is focused on the evaluation of the volumetric parameters on the cutting edge, on the size of the built up edge (BUE), and on the formation of the crater. Different coating types on the cutting inserts were used for the testing, and a IFM G4 microscope was used for monitoring and evaluating the tool wear.

The goal of this contribution was to describe the microstructure and properties changes of difficult to cut materials after turning. Surface residual stresses, roughness, microstructure of AISI 304 type stainless steel were studied as a function of side rake angle o. Residual stresses and phase composition of surface and sub-surface layers were determined using X-ray diffraction techniques. The presence of strain-induced martensite was investigated using Barkhausen noise, optical microscope, and microhardness measurement.

Microscopy is mainly used in tribotechnical diagnostics for the analysis of the total number and morphology of the wear particles in the lubrication systems. Wear particles may accelerate wear and ultimately may cause a failure in lubricating systems. Therefore, this paper deals the tribodiagnostic problem which is focused on microscopic analysis of wear particles and additional tribodiagnostic analysis of motor oil. There was taken sample of motor oil after failure of turbocharger of combustion engine. The purpose of the paper is to compare the results of microscopic analysis for evaluation of wear particles in motor oil. These analyses are key for assessing wear of the combustion engine and for indicating of impending failure. The aim of this experiment was to assess hypothesis that scanning electron microscopy (SEM) is appropriate for tribology diagnostics of seized turbocharger of internal combustion engine.

Extrusion process parameters play key roles in aluminum profile extrusion processes. In this literature, by using Box-Behnken experimental design to arrange the simulations using the ALE software HypereXtrude, Response Surface Methodology (RSM) were applied to study the simulation results and discuss the effects of five process parameters, namely billet diameter, billet preheat temperature, die temperature, container temperature, and ram speed, on the outlet velocity distribution uniformity of the profile named an Upper beam on the Train. The interactions between the five parameters also were investigated. Additionally, a second order response surface model between the extrusion process parameters and the evaluation criterion of outlet velocity uniformity was established. An optimization of the process parameters with the purpose to find the most uniform outlet velocity distribution was carried out based on the response surface model. The results show that the three parameters, namely billet diameter, ram speed and die temperature, have significant impact on the outlet velocity uniformity. And there are obvious interactions between these three parameters. After the subsequent optimizations, a more uniform outlet velocity distribution was obtained, and the final acceptable profiles were produced.

Productivity growth in the machining industry is associated with a reduction in the cost of cleaning and recycling contaminated process fluids. The proper use of process fluids or lubricants can bring a significant reduction in friction and the amount of wear, thereby leading to a reduction in power consumption. The use of nanolubricants in modern technologies is a major advancement. Nanolubricant is a new system composed of nanometer-sized particles dispersed in a base lubricant. The use of nanoadditives in the form of nanoparticles is highly efficient due to their high chemical and biological activity. The doping of lubricants with nanoparticles is one of the ways to solve problems with the removal of bacteria, whereby improving the biological, chemical and technological stability of process fluids. In the article, we monitor the effects of doping process fluids with nanoparticles of silica (SiO2) and titanium dioxide (TiO2) on the friction coefficient of friction pairs of Si3N4 balls against steel 16MnCr5, EN 10084-94 and Si3N4 balls against aluminium AlCu4BiPb balls.

This paper follows on research on published in the Journal of the Academy of Business & Economics [1] (authors Hron and Macak) and complements previous research on the area of design of experiments using a factorial design. Further results are compared between Fuzzy Logic and Design of experiment approaches.The main purpose of this paper is to compare the results between the mathematical model of optimization of CNC turning and the optimization using the fuzzy-logic method for multi-criteria optimization of cutting conditions. The comparison in this paper verifies these two approaches. In the case of an inconsistency, the objective of this paper would be to suggest a new approach where the incorporation of the mathematical model (as an approximation form) and the optimization of fuzzy-logic would be consistent.

The paper analyses the possibilities of modification of cutting tool geometry in order to preserve a protective plastic zone of material at a cutting tool. Based on the results of model experiment as well as practical verification, a rapid increase in tool life has been achieved. The tool life is dependent on the size of the shortened rake face. Optimization of the tool face size enables to achieve multiplied tool life when comparing with a classical cutting tool. A uniqueness of this processes is the formation of the two chips, one of which is a created plastic layer along the edge of the cutting tool. The application of the tool is possible only with the plastic material cutting. Experimental tests were realized with usually used steels.

The article presents the results from the application of a new method for raising the exploitation characteristics of metal-cutting tools, which includes preliminary combined magnetic field and ultrasound processing of the instrument. The indirect effect of the processing on the cutting force as well as on the roughness of the processed surface and on the wearing of the instruments during the drilling and milling processes has been studied. Demonstrated the effectiveness of the method on shear strength of the metal samples bonded

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.

Application of cutting fluids is one of the most widely accepted methods of increasing not only the efficiency of machining but also the quality management of the working surface that is used in industry. The cutting fluid market is large enough, and different manufacturers produce their own cutting fluids in several product lines which differ as to their chemical composition and their properties. When creating a cutting fluid, the manufacturer is particularly interested in the study of its individual properties as well as studying the effect of various chemical components on the final properties of the cutting fluid. Different methods are used to study various properties of cutting fluids. This article presents the method for the study of the tribological properties of cutting fluids. This method has been applied while comparing 5 different cutting fluids.

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.

Surface integrity reflects the properties of a material after it has been subject to some type of manufacturing process or modification during machining process and surface integrity can also have a great impact on a parts function. The changes limit the component quality or in the same cases performed the surface as an unacceptable. It has long been known that the method of surface finishing and combination of surface roughness, residual stress, cold work, or phase transformations strongly influence the service performance of manufactured parts as fatigue or corrosion. The main aim of the article is testing a high-productive reaming tool type MT3 with respect to different values of tool-life because holes making among the most important operation in machining and one of the most common in drilling operation.

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.

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 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.

Modifying of alloys is an important part of the metallurgical process and involves the course also of alloys of aluminum, specifically the Al-Si (silumin) in our case. One of the elements that it is possible used to modify for type of alloy Al-Si is antimony (Sb). This paper investigates potential impact of the modification of this element for AlSi7Mg0.3 alloy on tool wear in cutting process. Within experiments were made three casts of master alloy AlSi7Mg0.3 without additional modification and three casts from this ligatures that were more subsequently modified by 0.05 wt% Sb on the cast. These castings were then machined to the same cutting conditions and was assessed the resulting wear of inserts. The present experiment and analysis are part of larger research that are carried out at the Faculty of Production Technology and Management of Jan Evangelista Purkyně University in Ústí nad Labem.

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.