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This paper deals with the creation of a computational model of a particular cable manipulator composed of a rigid manipulator with three degrees of freedom and a platform driven by four fibers. Each fiber is led over a pulley and is driven by a linear motor, which can be controlled. The multibody dynamics approach is a suitable way in order to create the manipulator model. The most common cable modelling techniques are summarized in this paper and then the computational model of the cable manipulator QuadroSphere is created using MSC.Adams software. The computational model verification is done using the modal analysis of linearized model and the experimental modal analysis on the real set up. Further results of various numerical simulations are presented and their utilization is discussed.

The aim of the research was to evaluate the lapping length, the adhesive bonded surface treatment and the influence of the filler in the form of the aluminium microparticles on the adhesive bond strength. The alloy AlCu4Mg was the adhesive bonded material bonded by means of a two-component epoxy adhesive used in construction of machines. The filler in a form of aluminium microparticles was added into the adhesive. Laboratory experiments were performed on normalized testing samples of alloy AlCu4Mg prepared under standard ČSN EN 1465. Within the research three various treatments of the adhesive bonded surface were evaluated, i.e. without the surface treatment (WT), mechanical treatment of the surface (MT) and mechanical and chemical treatment of the surface (MCHT). The adhesive bonds without the adhesive bonded surface treatment (marked as WT) reach the smallest adhesive bond strength. When adding the filler in the form of aluminium microparticles (10 vol. %) the adhesive bond strength was increased of about 12%.

New types of process fluids is very broad. Drilling with constant feed force represents the experiment that follows different properties and effects in machining. The main aim of this scientific paper is to assess the speed of drilling holes by the drilling technology-constant feed force- with the drilling cutting tools made of uncoated high speed steel. Eleven different process fluids were compared used the during the experiment. There were compared eleven different process fluids. In the context of the thesis more process fluids from global suppliers have been tested. In the process of experiments there were used twist drills of high speed steel type HSS, ČSN 221121, ø 8 mm, without coating. Steel samples were 16MnCr5, according to EN 10084-94. During the experiment there was used drilling of holes by hand feed drill machine V 20 that was modified with the mechanical switch and there was also stopwatch. Testing of process fluids in chip machining has been going on at the Department of machining and assembly of the Technical University of Liberec for many years.

When constructing traffic means, agricultural machines etc. it is necessary to create a bond, namely from thin semi-products, i.e. sheets of metal. Namely light and strong materials such as e.g. aluminium alloys EN AW 2024 T3 (AlCu4Mgl) are used in the constructions. A research namely on the adhesive bonded surface treatment is necessary at a rise of the quality adhesive bond. The aim of the research is an evaluation of the adhesive bonded surface treatment of the aluminium alloy EN AW 2024 T3 (AlCu4Mg1) by means of mechanical tests and a surface analysis by means of SEM. A cyclic degradation loading of the adhesive bond after exposing the adhesive bonds to increased and decreased temperatures, i.e. in the interval -40 to 70 °C in a programmable climatic chamber MKF240 and connected adhesive bonded surface treatments were evaluated within the research. The adhesive bonded surface treatment was of the positive influence on the strength and the elongation of the adhesive bond and it increased the resistance to the cyclic acting of the degradation environment at the same time.

The aim of the paper is to compare a tensile strength and an elongation at break of the sandwich materials with different cores created with the polymeric composite mixture at simultaneous acting of the cyclic degradation. The sheet S235J0 is the face. The core of the sandwich panel is from the structural two-component adhesive, from the composite material based on the microparticles of the glass-bead, the rubber and the textile microfibre waste from the tyre recyclation and the rubber particle waste from the tyre recyclation. Namely the secondary raw materials based on the textile microfibres are difficult to utilize in another processing. This research showed one of prospective possibilities of the material utilization of this secondary raw material. The highest tensile strength of the sandwich materials is reached with the core from the composite material on the glass-bead base. The significant fall of the tensile strength of the sandwich materials was measured at the material with the core based on the rubber and textile microfibre waste from the tyre recyclation. The elongation at break was not almost changed. The core crackled at lower loading at first. The face tolerated higher loading.

The use of cutting fluid increases the tool life and reduces the roughness of the machined surface. However, during the machining the oil from the hydraulic system of the machine often gets into the cutting fluid, which can alter the properties of the cutting fluid. In scientific literature there is no information on the effect of the hydraulic oil entering the cutting fluid on the tool life and roughness. In this regard, at the laboratory of the Department of Machining and Assembly of the Technical University of Liberec, there has been conducted a study to ascertain the effects of hydraulic oil getting into different types of cutting fluids during the milling of stainless steel.

Equal-channel angular pressing is a method of severe plastic deformation, which implies high deformation into the material and leads to grain size reduction and strength increase. It was applied on a twin-roll cast Al-Mg-Sc alloy, which contained Al3(Sc,Zr) particles formed during annealing at 300 °C for 8 hours. The evolution of the microstructure and mechanical properties after deformation was studied during isochronal heating 50 K/50 min. Strengthening occurred during annealing at lower temperatures and was followed by prominent microhardness drop, which was connected with formation of new grains and recrystallization. The presence of Al3(Sc,Zr) particles in the matrix is accounted for the high temperature stability.

This paper describes a modelling methodology that predicts a contour of a pneumatic tyre in the curing mould. Tyre contour is designed to be in the equilibrium shape. Such shape is described by a system of complex mathematical equations that has to be solved numerically. In this new approach a standard FEM software is employed to gain the shape without the need of dealing with these equations manually. The quality of the proposal of FEM approach was assessed by comparing the meridian to a verified solution for several tyre constructions and sizes. Selected results are presented to show the accuracy of the FE modelling procedure. Nowadays, most of the produced tyres are of a radial construction. Therefore, this paper deals only with radial tyres.

The stability of the machining process is depending on the machined materials properties. But the material properties are influence by the heat treatment process and in this case it is forging. For these study three different company made the "same" forging process and then the material properties are evaluated and their influences on the cutting process were monitored. For the tests the steel DIN 18 CrNiMo 6-7 was used. This material is typically used for the gear wheels where the cutting tools by tool steel is used for the machining. So for the tests the mills from tool steel were used and during the machining the cutting tool life and cutting forces were monitored.

Present work is focused on the study of recycled AlSi8Cu2Mn cast alloy. Furthermore, the effect of Sr-modification (0; 0.03 and 0.05 wt. %) on the microstructure, tensile and impact properties (UTS, ductility, hardness and impact energy) were investigated. For study and identification of intermetallic phases were utilized standard, colour and deep etching (in order to reveal the 3D-morphology of the Si-particles and intermetallic phases). For element composition of the specimen was used X-ray analysis. Finally, the effect of Sr-modification on silicon morphology was examined. The results show that the addition of Sr into AlSi8Cu2Mn cast alloy should act as a modifier, so it supposes to change the eutectic Si-morphology. However, its effect as a Si-modifier is not as significant. Higher number of iron (1.1 %) leads to an increase of precipitation of brittle iron phases with platelets (Al5FeSi) and skeleton-like (Al15(FeMn)3Si2) morphology. Al5FeSi platelets act as preferred crack sites and reduce the tensile and impact properties. Strontium not only refined and modified eutectic Si, but also modified the Al5FeSi needles and thereby improves tensile (first of all ductility) and impact properties. Sr addition is also associated with porosity formation.

Additive manufacture (AM) is a promising tool to produce sophisticated parts, for example for automotive and aircraft applications, as it excels in astonishing geometry freedom. For such applications, aluminium alloys are of a particular interest thanks to their excellent strength-to-weight ratio. In comparison with the conventional casting of aluminium-based materials, AM brings about some characteristic features; especially unique microstructure evolution. For the real use of additively manufactured parts it is thus important to compare material properties obtained by AM with the cast state. Therefore, this paper brings a comparison of AlSi10Mg alloy produced additively by selective laser melting (SLM) technology with conventionally cast alloy. It is focused on microstructure characterization and mechanical properties assessment. Results of this comparison show that SLM yields very fine microstructure, what reflects in significantly higher mechanical performance over cast material.

Concerning with effort to replace hard chrome plating cause of its ecological issues, this paper investigates the effects of surface technologies to wear resistance of ISO 42CrMo4 steel, which is popularly used in weapon production. After quenching and tempering, the experimental samples were treated by nitrocarburizing (tenifer), hard chrome plating and plasma nitriding technologies. Plasma nitriding was carried out with different gas mixture at 500ºC (plasma nitriding process) for 15h. The wear test based on principle "pin on disc" was performed to evaluate the coefficient of friction and the wear rate. The results were supplemented with surface hardness test and metallografical evaluation. The experiment results point out that nitrocarburizing and plasma nitriding improve wear resistance better than hard chrome plating.

Main aim of this article and research is to describe exact influence of key parameter in injection molding process. This key parameter is temperature. Nowadays is possible to use wide range of advanced virtual simulation tools, which were in research used. Article is focused on determining optimal temperature of injected plastic material, temperature of mold and temperature of coolant. For veryfing of virtual method was performed real injection molding with same input parameters and results were compared. For evaluating of achieved quality was investigated influence on whole molding process and influence on final product properties. As testing material was choosen High-Density Polyethylene with properties described in article.

The article deals with some aspects related to the machining of surfaces that have been deposited by wear-resistant hard coats using HVOF (high velocity oxygen fuel) technology. HVOF coating is a thermal spray process used to improve a component's surface properties, thus extending equipment life by significantly increasing errosion and wear resistance, along with corrosion protection. For a purpose of this research, the chromium-cobalt alloy - Stellite 6 was used as a sprayed material. Considering that the parts made of stellites are widely used in various industries and very popular in specific applications, it is a big drawback that adequate machining processes for stellites have not yet been developed other than the costly and time-consuming technique of grinding. However, in this research, an attempt has been made to reveal the optimal machining parameters for a lower value of surface roughness for the purpose of successful machining of Stellite 6 using inserts with various radii of cutting edge. Authors have evaluated the quality of machined surface not only by means of Abbott curve, but they have also observed the dependency of arithmetical mean roughness value on both cutting-edge radius and feed. The analyses of cutting tips wear at changeable inserts have shown that typical wear appears in the form of a notch.

The paper deals with the monitoring the metallurgical purity of alloy AlSi9Cu3(Fe) both in the dependence on the input material quality and on the manner of the melt metallurgical treatment. Experiment was divided into two phases. During the first phase there was monitored the metallurgical purity of the input material delivered from the different suppliers. During the second phase was at the standardly prepared melt observed the influence of the degassing time on its metallurgical purity. To evaluate the input material metallurgical purity, Drosstest was performed and subsequently also the metallurgical evaluation of samples. To determine the influence of degassing time on the metallurgical purity of melt, Density index (DI) was monitored. By this index it is possible to evaluate the amount of inclusions and dissolved gas. Based upon the measured values there was determined the degassing time needed to achieve the required values of DI.

An extensive experimental investigation was carried out to study the performance of Stellram Indexable Milling Cutter (XDLT09-D41), used for rough down milling of Ti-6Al-4V alloy. The machining performance was investigated for small depth of cut under different combinations of the operating parameters; like application of high pressure coolant and their impact in terms of tool wear, tool life, thermal crack, etc. The range of operating parameters were broadened, to get comprehensive results in comparison with previous work. The critical observations of the tool wear were at the tool tip/nose and at the bottom part of tool; where thermal deformations were most likely to be propagated with time. It has been noticed that the flank wears were owing to scratching of the cutting chips and diffusion wears were because of high thermal stresses at the bottom of the cutting tool. These findings are in consistent with literature; moreover, the optimum operating parameters were further enhanced to achieve superior performance. Integrated methodology maximized tool life to the moderate speed of 40m.min-1, feed rate of 358 mm.min-1 and depth of cut of 0.8mm. It is generally concluded that the cutting performance has poor relation with alloy properties compared to the operating conditions.

In present paper, the growth process of the phosphate coating on S355J2 steel was investigated. The microstructure, surface morphology, coating thickness, surface roughness and corrosion resistance of the phosphate coating were analysed by using several techniques including light microscopy, confocal laser scanning microscopy (CLSM) and electrochemical tests - electrochemical impedance spectroscopy (EIS) in 0.1M Na2SO4 solution (simulation of industrial atmosphere). The phosphate coating formation was evaluated after chosen exposure times from 15 minutes to 105 minutes in phosphating bath composed of MnO2, H3PO4 and demineralised H2O. The optimal exposure time of S355J2 steel in selected phosphate solution was determined from surface quality, corrosion resistance and energy consumption point of view.

Al-Zn-Mg-Cu alloys possess excellent mechanical properties, and therefore are used in aerospace and automotive industry. However, they are susceptible to localized corrosion such as pitting, intergranular and exfoliation corrosion, which is closely related to the precipitate size and distribution. Because the size and distribution of the precipitates are controlled by heat treatment, we investigated the influence of the heat treatment on corrosion behaviour and mechanical properties of the AA 7075 alloy. Audi test, internal Audi standard PV 11 13 for automotive industry, was chosen to evaluate the corrosion behaviour of the as-cast, T5 and T6 heat treated aluminium alloy 7075. Mechanical properties were studied through the tensile test and hardness measurements. The highest corrosion rate and the depth of corrosion attack penetration were observed for the T5 state, while the T6 state evinced the best resistance to localized corrosion and the highest mechanical properties.

The submitted paper presents possibilities of a simulation for a real manufacturing process in a company taking the risks into consideration. The risks may result from various sources in manufacturing environment. The most significant ones include a human factor, the processes in general and environs where the manufacturing process takes place. Risk can be viewed as a state where there is a possibility of a loss but also a hope of gain since one would never jeopardize the loss if there were no chance of a win. Because of the argument that a risk is perceived differently depending on the observer's experiences and objectives, it has become increasingly important in organisations to create awareness and gain information of potential risks. The paper is aiming to present the possibilities how to avoid such risks or to decrease them to an acceptable level through simulation and modelling tools.

Machining of titanium is quite difficult and expensive. Heat generated during the process of cutting does not dissipate quickly, which affects tool life. In the last decade ultrafine-grained (UFG) titanium has emerged as an option for substitution for more expensive titanium alloys. Extreme grain refinement can be readily performed by severe plastic deformation techniques. Grain refinement of a material achieved in this way was shown to change its mechanical and physical properties. In the present study, the microstructure evolution and the shear band formation in chips of coarse grained and UFG titanium machined to different cutting speeds and feeding rates was investigated. It was demonstrated that an improvement in the machinability can be expected for UFG titanium.

The quest for light and stiff structures by industries such as the medical industry and the aerospace industry is the driving force behind developments in additive manufacturing technology. One way to achieve significant weight reduction of components is by deploying periodic porous structures. Various types of porous structure geometries use material with varying efficiency, and therefore vary in their resulting mechanical and physical properties. This article focuses on the lightweight Schoen Gyroid cellular structure, which could offer a suitable combination of the desired mechanical properties. The goal is to determine the effect of the volume fraction on the load capacity of the gyroid structure made of maraging steel using DMLS technology. We conclude from the experimental measurements that the results could be affected by several factors, which are detailed at the end of article.

The article deals with testing of the resistance against Foreign Object Damage (FOD) on leading edges of blisks (blade disks) in turboprop engines made of Ti6Al4V alloy. Such damage can occur during operation, when rapidly rotating compressor parts on the engine intake are exposed to foreign particles. E.g. operation of small passenger aircrafts in desert areas, where large amounts of foreign particles occurs in the atmosphere. The paper describes the development of method for testing the resistance of the leading edge of the blades against FOD in order to mimic the conditions of operational damage. Further it quantifies potential benefits of modification in the geometry of the blisk leading edge and compares results of FOD resistance of sharp leading edge and modified geometry. Results of metallographic analysis for deformed areas near the FOD on Ti6Al4V alloy are also presented.

Article deals with the during operation of pneumatic dosing device designed for die casting machines where the metal level in the furnace decreases stepwise by which the period of dosing of the filling mould is prolonged. We also deal the regulation of delimitation of metal level decrease in the furnace based upon the pneumatic principle.

The paper deals with the mathematic modeling of the liquid turbulent flow in the pipe with circular cross-section. The aim is to compare two methods of solution for various geometries and Reynolds numbers. One of the methods is simulation of the system in the commercial software ANSYS Fluent, the second one is analytical solution for simple geometry by equation usually applied in the common design process. The work arises from the requirement to design the computational model based on the FVM, which enables to simulate the various physical phenomena which appear at liquid flow. The solved problem is quite range and therefore the work is only the first part of the systematic investigation. This basic part is important for the decision of the suitable software tools, turbulent model, etc. The investigation of the heat transfer on the cross flow over the tube placed in the bounded surrounding.

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.

Projecting and designing of automated assembly cells/lines is very complicated process. The rising demand on an assembly high quality, precision, effectiveness and shorter time to market. Puts the high requirements on the all active devices which act at the automated workplace. Assembly robot with its effector influences the effectiveness of the proposed assembly automation very significantly. Design or choice of the assembly robot and its robotic gripper namely is very important step of the automated assembly cells/lines projecting. Secure and stable holding of an assembly object by robotic gripper is one of significant conditions for trouble-less execution of the object automatic implementation into assembly joint. This article presents our experiences with utilization of advanced simulation methods for the specialized robotic gripper grasping ability exploration for purposes to evaluate a safe and stable grasping of different objects. Virtual reality tools - eon reality and haptic device with glove and finger actuators (CyberForce) were applied for simulation experiments realization too.

Introduction into problems - the present CAD/CAM systems integrate part modelling and engineering design, proposal of technological documentation in the form of NC programs and operational management of production within a one computer system. Their utilization allows the programmer to create machining technology, to define the tool paths and to generate NC programs for very complex shape parts [7]. Final product of CAM system is CL Data files, which include all the steps of toolpaths and technological process. If we want to connect the information produced by the CAM system with the concrete CNC machine, we need to use NC postprocessor. Generator of postprocessors to help users faster creates the specific postprocessor. Universal postprocessor does not exist. Unfortunately, it is necessary to create and to program it for each machine separately. This paper presents a use of the software tool "Constructor of postprocessors", by the creation of postprocessor in CAD/CAM system Edgecam. Postprocessor was developed for turning machine EMCO Concept Turn 55 with control system SIEMENS 840D at the Department of Automation and Production Systems (DAPS) Faculty of Mechanical Engineering.

The paper deals with the methodology and suitability of mathematical models applying analysis of the signal-to-noise (S/N) ratio as well as analysis of variance (ANOVA) and surface response methodology (RSM) on effect of TiAlN coating on chip ratio when drilling with HSS Co5 twist drill with diameter of 8 mm. Experimental work was performed according to design of experiment (DoE) Taguchi method. Cutting speed vc (m/min) and feed f (mm/rev) were selected as control factors in three levels and chip ratio K was used as a response variable. The main aim of this study is to establish relevant methodology for short term testing and find adequate mathematical model for chip ratio parameter K = f(vc, f) as a function of cutting condition when drilling with PVD coated and uncoated tool. Statistical software Minitab 14 was employed to process and evaluate of experimental data. The effect of feed and cutting speed on chip ratio was investigated through analysis of the signal-to-noise (S/N) ratio and analysis of variance. Equations for chip ratio K as a function of control factors were developed.

The paper dealt with the influence of geometric asymmetry on the vertical vibration of symmetrically or asymmetrically loaded mechanical system. The system is composed of rigid flexibly linked elements. Kinematic excitation was carried out by a unit jump (jump of the springs), excitation of system was symmetric and asymmetric. The system of elements was examined experimentally and numerically. The numerical model was verified by experimental solution. Numerical solutions were carried out by finite element method (FEM) applied to model that respected the design and conditions of the laboratory model for experimental investigations. The aim of the work was to create a numerical model based on the finite element method and to verify the results of the model. The obtained results can be applied to flexible storage machines.

This research investigates the influence of repeated use of the Al-Cu-based alloy. In our case we used the alloy RR.350. Specimens for the tensile test were cast into a metallic mould, to which a protective coating was applied. Altogether 15 specimens were prepared from each melt in order to obtain more accurate results. During casting the temperature of metal and mould was controlled from the viewpoint of ensuring constant conditions of the experiment. Test bars were prepared from the cast specimens for measurement of tensile strength at normal (20°C) and elevated temperatures (up to 350°C). Furthermore parts were taken from the cast specimens for measurement of hardness (HB) and for metallographic analysis. Thermo-mechanical properties of the investigated alloy were determined at the working site of the authors - Department of Metallurgy and Foundry at the Faculty of Metallurgy and Materials Engineering, VŠB - Technical University of Ostrava. This experiment has unequivocally confirmed the negative effect of repeated use of the investigated alloy on its thermo-mechanical and structural properties.