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This paper is dealing with the influence of mould strength on a shrinkage production for ductile iron castings. According to pressures that impact a mould cavity the strength of mould is an important parameter by ductile iron pouring. During the solidification of cast iron a non-metallic particle - graphite is released. Depending on graphite amount released in the liquid and in the solidified skin of casting the tendency to shrinking is varying. In the experiment a furan sand mixture is used. The experiment compares a size of the created shrinkage in the castings with different wall thickness poured into a moulds with different strength. For the occurrence of shrinkage and its size evaluation a non-destructive ultrasonic reflecting method was used.

All technical metals used not only in agriculture are subject to degradation processes, there are distinguished two main types: mechanical abrasion and physical-chemical degradation (corrosion). In order to lower abrasion of a machine part, it is necessary to use appropriate technical materials as well as an appropriate heat treatment. To minimize losses caused by corrosion, an appropriate anticorrosion system has to be used. This paper evaluates corrosion and mechanical resistance of waterborne acrylate anticorrosion systems sold on the Czech market. These paints were applied by an air flow technology. Mechanical characteristics of the applied coating were evaluated according to the ČSN EN ISO 4624 (pull-off test for adhesion), ČSN EN ISO 2409 (cross-cut test) and ČSN EN ISO 1520 (cupping test). As used anticorrosion systems were applied also on zinc-dipped coating, this duplex system was also subject to the mentioned tests. Corrosion resistance of the tested anticorrosion systems was analysed in the salt-spray environment (ČSN EN ISO 9227). Based on the results of the individual tests, there can be characterised adhesion, flexibility and mechanical resistance of waterborne anticorrosion systems as well as a further application on zinc layers. Corrosion tests analyse the process and visual appearance of corrosion attack.

Laser beam welding is an industrial technology that has seen a significant development from the early stages up to the present. Technological process management ensures high product quality as well as enhanced productivity and competitiveness. The aim of the research is to determine the impact of welding parameters by fiber laser beam on the quality of weld joints from aluminium. Basing on the presented quality assessment methods and computer simulation, we evaluate the weld joint samples. Finally, we discuss optimal welding parameters and conditions allowing the production of weld joints of the desired properties.

The design of internal combustion engine use plain bearings, pistons and piston-rod which are based on aluminium, brass. Further are used steels with coating based on aluminium and bronze. The paper describes the impact of contaminants in motor oil on wear of materials, which are used in production of parts of internal combustion engine. Reichert tester M2 for evaluation the lubricity from Petrotest Company was used in order to assess ability of motor oils to create proper lubricating film. Reichert tester M2 belongs to a group of equipment simulating real frictional contact. Wear particles come into oil in lubrication system, where they cause contamination and degradation of lubricating properties and consequently it may result in major failure of machines. Among these contaminants are included mainly water, fuel, water coolant, adhesive, abrasive and fatigue particles wear. The aim of research was focused only on oil contaminated with fuel including petrol, diesel and biobutanol.

Nowadays manufacturers currently use about 35 % of secondary aluminium and about 65 % of primary aluminium to meet their needs. The production of secondary Al alloys have significant advantages. Most important is saving of natural resources with a consequent material cost reduction and a considerable energy-saving associated to reduction in pollution and CO2 emissions. The positive fact is that secondary Al alloys has comparable mechanical properties with primary aluminium alloys. Therefore it is necessary to study properties such alloys especially those which are used for transport industry in order to keeping the quality of casting. One of the major properties of casting for transport industry are fatigue properties. Research point to the fact that more than 90 % of broken engineering components are fractures caused by fatigue of used material. Extremely dangerous are fatigue fractures in transport, for example rails, tire parts, plane wings and hulls of ships, because these are usually connected with human casualties. Due to this fact were studied fatigue properties of aluminium alloys used especially for automotive castings - AlSi9Cu3. The great object was influence of casting to the different mould (sand and metallic) without modification, heat treatments or grain refinement of experimental material to fatigue resistance of the casting. This work shows differences between materials properties which were casted into the different mould.

Aiming at the problem of platform planning and module identification in product family design, modular theory, implementation methods and objectives are studied in mass customization(MC), and a dynamic planning model is established for product platform and module. Firstly, the versatility and physical consolidation of existing variants are analyzed and expressed using directed and undirected graphs. And then a dynamic planning algorithm, in which the platform threshold and the module boundary parameters are set dynamically based on market demands, is proposed in product platform and module design. Secondly, potential parts are extracted for more variant products in product family design. Finally, the effectiveness of the proposed approach was demonstrated by the dynamic planning for parts of different humidifiers.

The aim of this paper is the comparison of selected rheological properties of polymeric composites with glass fibers materials before and after exposure in UV box. Rate and depth of degradation induced by the environment were evaluated by Frequency Sweep Test, which monitors changes in viscoelastic properties of polymers with respect to their molecular structure and their behavior in thermoplastic processes. Degradation process resulted in changes of complex dynamic viscosity, storage and loss modulus, changes in molecular weight and its distribution. UV radiation is intense degradation factors affecting the change in the structure and properties of polymers - the polymer matrix gradually degrades by UV radiation, the viscosity of the composites decreases, the COP is moved to lower angular frequencies with increasing molar mass.

This paper deals with the description of a mechanism for calibration vehicle axle scales with a loading capacity up to 10 tons and strength analysis of its selected part. The strength analysis will be carried out in ADINA software and this analysis results will be used to check the safety of the structure and in case of exceeding the permissible stress, deformation, etc. This analysis results will form a benchmark material for optimisation of this structure. The next step of this issue will be strength analyses of all important parts, i.e. boxes with weights and upper girder. After performing these calculations and the resulting optimisation, the prototype production will be feasible.

This paper presents a kinematic and dynamic analysis and distribution of the stress in items of a planar mechanism by means of the MSC ADAMS software. Graphic dependence of kinematic and dynamic magnitudes of some points is given in dependence on the angle of rotation of the driving item and in dependence on the time. Distribution of the stress in the items presented is in [ Pa ]. In relation to the kinematic and dynamic analysis and subsequent simulation of the planar as well as spatial mechanisms, it is great solution to use MSC Adams software program. The considerable advantage of this mentioned program is based on its simplicity from the aspect of modelling and moreover, it is important to point out that utilisation of the mentioned program leads to results which are precise and accurate in the case of the numerical solution of the equations in the whole magnitude referring to motion of mechanism while the given results are obtained in the graphic form.

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.

Metal additive manufacturing (MAM) is used in the production of parts, where a product is built layer by layer. MAM includes Direct Laser Metal Sintering (DMLS), which allows the production of complex metal parts directly from 3D software models without using sometimes expensive tools such as moulds, dies and cutting tools. New possibilities in the production of complicated components are made available using this advanced manufacturing technology. Nevertheless, this technology has limits, resulting from the method of melting in the powder bed. Therefore, this paper investigates the ability to produce fine cellular lattice structures. Some structures with self-supporting cell units were selected for experimentation and were produced with identical cell size and volume fraction. Based on this, a suitable topology was established for the production of fine structures with small volume fractions.

Nowadays, there is effort to substitute in aerospace industry so far commonly used alloys (especially nickel alloys) with new low-density materials, which will have comparable mechanical properties and good resistance against high-temperature oxidation. Ti-Al intermetallic alloys are in this trend modern, already-used material. The results of the tests show that further enhancement of properties can be achieved by addition of silicon. The disadvantage of these materials is a low fracture toughness at room temperature and difficult production. Powder metallurgy seems to be a way to replace still used melting metallurgy. In this work, cyclic oxidation of Ti-Al-Si alloys prepared by reactive sintering, milling and Spark Plasma Sintering is described. The TiAl10Si30 alloy was evaluated as the best alloy from tested ones, because was the most resistant to the stresses. Stress was induced into the oxide layer by repeated annealing and cooling.

Material standards of commercial alloys are key documents for casting producers as well as for their customers. Compliance with the prescribed chemical composition of alloys should be the basis for achieving their constant and reproducible properties. Material standards, however, in many cases tolerate contents of alloying elements within a relatively wide range, which can lead to very significant differences in mechanical properties of alloys. The differences in behavior of selected aluminum alloys with chemical composition on the lowest and highest contents of alloying elements prescribed by their material standard are documented in this paper. Significant differences in properties of alloys with chemical composition at lower and upper limits given by their material standards were found. These differences were further enhanced after heat treatment of alloys.

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.

Under the influence of heat load and Zn diffusion in resistance spot welding of galvanized steel sheets, significant changes occur on the contact area of CuCrZr welding electrodes which lead to their erosion damage. Changes, causing wear of electrodes not only affect the welding process but also the quality and properties of the weld. Apart from the traditional solution (for example, the so-called "Slope" welding current) the wear of the contact surfaces can be affected by using the barrier layers - coatings. Main goal for the use of material barrier is to minimize the structural changes caused by Zn diffusion, erosion and higher heat resistance of the electrode. Recent studies have shown that such a suitable coating is a multilayer system (Ni/TiB2).
This paper is focused on the assessment of changes in the contact area of the electrodes and the barrier layer Ni / TiB2 after compila-tion 0, 1, 5, 20 and 100 welds on galvanized steel sheets type HX220BD Z100MBO.

Ride of vehicles along curved track is a serious technical problem, which for the long term requires attention of vehicle engineers as well as track designers. It is especially interesting to observe behavior of tram cars passing a curved track, because they should be able to pass arcs up to 17 meter radius. Ride of a vehicle along such strongly curved track is nowadays accompanied by significant wear in rail-wheel contact, increased bogie and track stress and by generation of noise. One of the key causes of this unfavorable phenomenon is an increase of slip velocities in rail-wheel contact. This paper is based on simulation analysis, which compares different ways of minimizing slip velocities and thus mitigating the impacts of passing vehicles on the track as well as on the car itself. Bogies with and without wheelset steer possibility were analyzed. Both bogies were also analyzed with wheel profiles of different delta R function course.

The creation of the heterogeneous joints at materials with the different physical and mechanical properties is always problematic. As one of methods by which can be achieved very good results is there a diffusion welding. The aim of paper is to show the possibilities of diffusion welding utilization at creation the heterogeneous joints between Titan grade 2 and high-alloyed austenitic steel AISI 316L. The fundamental theory of diffusion and also scheme and realization of experimentally created diffusion welds in the thermal-mechanical simulator Gleeble® 3500 is described in the article. Furthermore, procedure of technological parameters selection when optimization of heterogeneous joint strength properties including metallographic evaluation are taken into account, are also presented.

As a result of globalization the aspects of raising productivity and speed of production with extreme requests on the flexibility of the production systems are gaining importance. These aspects of production are affected by type of product and production and mainly by the capability of companies to correctly manage the manufacturing process. Manufacturing process is globally quicker than it was and the areas of logistics and production planning are still gaining more importance. Gradual changes are also in complexity of production. Without modern tools for production planning it would be very hard to manage production effectively. These tools are part of digital factory concept. Because of those tools the effective planning of production and utilizing the production facilities capacity to its fullest is possible. This paper describes development and implementation of the digital factory concept and its tools in our partner company and is built on previous paper dedicated to common implementation principles of digital factory tools. The main goal of digital factory implementation was optimization of the Tricanter production planning process, elimination of bottle-necks of production system and optimization of manufacturing facilities capacities utilization.

The paper deals with a machining of the aluminium alloy by means of an unconventional technology, i.e. an abrasive water jet (AWJ). The paper deals with a study of an influence of the abrasive water jet at its impact on a surface of the machined material, i.e. the aluminium alloy AlCu4Mg of a thickness 20 mm. A topography of the machined surface is evaluated within the research by means of roughness parameters. A surface analysis is also evaluated by means of a scanning electron microscopy (SEM) depending on a cutting speed and a mass flow of the abrasivum. The research results proved an increased influence of the cutting speed and the mass flow of the abrasivum. The optimum cutting speed was 50 mm.min-1, the cut was uniform without a significant grooved zone typical for cuts by means of AWJ technology.

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.

Drawing spinning is widely used for the manufacture of cylinder parts from disk blank. And the roller path can affect its formability strongly. But how does the effect mechanism work is rarely revealed. The plastic of the metal is one key factor for the failure of spinning such as fracture and wrinkling. In order to reveal the relationship between the roller path and the formability, two working conditions with one-pass (Scheme I) and multi-pass (Scheme II) roller path are proposed. And the comparative analysis of their metal flow evolution is carried out by the finite element method. It is found that one-pass roller path isn't conducive to putting down the flange gradually. And this will bring larger deformation resistance to cause cylinder wall fracture and reduce the formability of drawing spinning.

The article deals with the calculation of temperature, the maximal solubility of the solid solution and determination of the eutectic temperature of the system Al-Si under the influence of elevated pressure. Monitoring effects of pressure on the equilibrium system Al-Si has an importance for the study of the crystallisation of aluminium alloys under pressure. Alloys based on aluminium and silicon, commonly referred as silumin, are the most important foundry aluminium alloys. First time binary alloys of this type were made by French chemist Sainte-Clair Devil more than 150 years ago. They showed low mechanical properties (Rm = 98 / 117 MPa, A = 1 / 3%). That changed in 1921 when the American A. Pacz discovered the effect of sodium on the crystallization of these alloys, that achieved thanks to this a significant increase in mechanical properties (Rm = 166 / 225 MPa, A = 2 / 8%). Recently, these alloys are processed by squeeze casting (crystallization under pressure). Casting alloys with high corrosion resistance, low coefficient of linear shrinkage, satisfactory mechanical and casting properties (excellent fluidity, low tendency to shrinkage during moulding), which moreover are good in welding and brazing [1, 2, 6, 8, 15, 18, 19, 20].

A new comparison method of the total forces for different contact areas has been published which allows increasing determination accuracy for cutting forces on flank surface. In this regard, on the basis of the new method the laboratory of the Department of Machining and Assembly of the Technical University of Liberec has carried out a study to determine the effect of tool wear on the correlation of forces on the face and flank surfaces of the cutting tool when cutting various materials.

In the last decades, advanced brake technology in the port sector follows the global productivity developments of the international maritime trade. Container vessels are getting bigger and bigger and the ship to shore cranes is getting consistently higher. But service, emergency or storm brakes cannot be getting bigger and bigger to meet these increasing demands. Throughout history, innovations and advancements in technology have made industry better through automation and increased efficiency. No matter how advanced industry becomes, the need for emergency duty stopping brakes will not go out of style because there are always circumstances that require mechanical brakes to do the job. Brakes will invariably insure against those rare, yet potentially catastrophic events that even modern technology cannot defend against.

In a competitive market the manufacturing companies have to produce cost effective products which can be realized by minimized production cost and higher effectiveness. The application of Lean manufacturing philosophy in order to optimize costs and quality is gaining a competitive advantage. There are lots of Lean tools which can result the improvement of the production line performance.
The article is original and unique, because beside the description of theoretical background relating to the process improvement, a practical method is also introduced in a case study.
In the study the author describes the main general steps of a Lean project completed in an industrial environment. The described case study which is a part of a real R+D project shows how can be improved the efficiency and reduced manufacturing cost of a real manufacturing system by application of several Lean tools which are One-piece flow, Takt-time analysis, Line balance and Cellular design.

This work deals with the issue of tapping Inconel 718 alloy. This material is known for its unique properties of high strength at high temperatures, corrosion resistance, high hardness, work hardening and low thermal conductivity. The machinability of Inconel 718 is very hard and cutting tool wear is high.This paper deals with creating internal threads by using monoliths taps. The taps are made of powder metallurgy high speed steel.The taps were provided with coating. Preparation of the hole for the thread has a huge impact on the cutting tool life. If the preparation is poor the inner face of the hole will be work hardened. This makes the cutting tool life far shorter. For the test, taps with different threads per chamfer were used. The second part of the paper is focused on the experiment where cutting tool life was monitored.

Modular fixture is conventionally designed less concerning the detailed specifications of machine tool. A little of literatures involve the effectively application to the existing CAD systems in CAFD (computer-aided fixture design). The determination of the validity of modular fixture during NC machining lacks for a practical method. This paper put forward that: Firstly, the feature-model repository of elements of modular fixture can be built in CAD packages; the design of modular fixture in NC machining should be accomplished under the concept of NC Manufacturing System (NMS); the Post-NC verification can be applied to check the performance of modular fixture applied in NC machining. Part 1 of the paper focuses on the feature-model repository of the modular-fixture elements. The other jobs will be introduced in the Part 2.

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.

The article presents an investigation of the influence of coating deposition parameters, in particular a variation with 50% of both cathodic arc current and bias voltage, on the mechanical and tribological properties of TiCN coatings on an aluminium substrate deposited by the cathodic arc evaporation of metals at a constant gas flow ratio between C2H2 and N2 of 17.65 % / 82.35 %. The determined nanohardness values for the samples examined are in the range of 10 to 23 GPa. Surface morphology and chemical composition were estimated by a scanning electron microscope (SEM) and an energy dispersive spectrometer (EDS) of SEM. The tribological behaviour of the TiCN layers was examined using the "Ball-on-Disk" method (ASTM G99-95) and using a ball made of Al2O3 as a counter-part and a load of 10N. The friction coefficient was measured in the range of 0.182 to 0.116.

The article presents the microstructure and mechanical properties of two types of aluminium alloys AlSi10 and AlSi5Mg. The structure and mechanical properties as a tensile test of two alloys AlSi10 and AlSi5Mg were studied and compared. Gravity casting is very good process for making complex mechanical parts of low density metals like aluminium alloys. Therefore our samples are prepared by gravity casting technology. Light metals have come to the forefront in the automotive industry and improved fuel economy. Therefore, we compared the AlSi5Mg alloy with a commonly used alloy AlSi10. This type of alloy AlSi5Mg has excellent casting and technological properties (good machinability and corrosion resistance). We are engaged with the issue of the production of castings for the automotive industry, at our department the Department of Engineering Technology-Technical University of Liberec, many years. Currently, we are focusing on aluminium alloys, their metallurgy and crystallization conditions with minimal internal defects.