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

The aim of the research was to identify and analyze the nature and causes of black inclusions formation on a cast surface of AlMg3 alloy. Forms used in tires production are made of AlMg3 alloy by low-pressure casting technology. Four areas with the same shape and coloring of inclusions are marked on the figure Fig. 1. These areas underwent macroscopic and microscopic analysis. In regions of inclusions appearance several surface EDS analyzes were performed with the aim to determine chemical composition of the inclusions. EDS analyzes showed that the inclusions are in fact Al2MgO4-type spinel inclusions which appear for Al-Mg alloys with higher amount of Mg (above 1 - 2 %). As far as the theory of the problem is concerned, possible causes of spinel inclusions formation are described in the literature [1, 2, 3, 4]. Other possible causes of spinel inclusions formation considering low-pressure casting of AlMg3 alloy found during long-term research of low-pressure casting of Al-Mg type alloys are mentioned in [5].

This paper presents some analysis of color metallography in the identification new structures of aluminium alloys. For experimental purposes aluminium alloy from the group hypereutectic AlSi7Mg 0,3 silumins was used. Alloy and modified using calcium in the form of master alloy AlCa10. The master alloy AlCa10 in the analyzed alloys added to improve the technological properties af alumium alloys, especially fluidity and machinability while maintaining sufficient corrosion resistance of the alloy. The analysis and evaluation of individual structural components are used method of color etching. The analyzed alloy was also subjected to the method of the black and with contrast what, but not of this paper subject. The application of color metallography is possible to differentiate and identify the presence of the intermetallic particles with different chemical composition.

The aim of the performed works was research on the causes of formed aluminum blanks cracking in the range of the AlCuSnBi alloy rods where cracks appear during mechanical machining (turning, drilling) of this range to the final part. AlCuSnBi alloy was invented as a substitute for aluminum machining alloys Al - Cu type alloyed with lead. For the alloy were performed qualitative and quantitative fractographic analysis of the fracture surface after machining in order to determine possible causes cracking of the material and thus his lack of strength during machining. Part of this paper is to the overall theoretical analysis of the issue. This paper clearly documents that fractographic analysis methods can significantly and to the extent required to provide answers to the causes of insufficient material strength during machining. Also points out the possible causes of cracks in this alloy during machining and ways to eliminate them.

This paper reports on the outcomes of an investigation concerned with the machining performance of thermally treated recycled glass in the vibratory mass finishing process. The surface finish generated with the glass is compared to that achieved using conventional polyester bonded media under different lubrication conditions. To help understand the wear behavior of the glass, measurements of the surface topography were obtained at intervals throughout the tool life, using a replication method. A further series of tests were undertaken to establish self-attrition rates. It has been demonstrated that the machining performance of recycled glass media is comparable to that of conventional media in respect of surface finish (Ra), brightness cycle time, self-attrition rate and tool life. This innovative work provides strong promise for the introduction of this new media into the abrasives marketplace for polishing, superpolishing and superfinishing of engineering materials.

The article describes typical damage of rolling bearings and basic methods of their detection. From various methods of working bearings diagnosis the vibration method selected. Vibration signal contains a series of important technical information about the machine condition and is currently the most frequently used in diagnostic bearings systems. Furthermore, structure of vibroacoustic signal the frequency generated by the damaged bearing depends on the causes of the damage, the phases of its development and in particular the size of signals from other kinematic nodes, load, service quality and environmental impact. Monitoring the dynamic state of bearings nodes can carry out repairs technical conditioned by state of machines and omission preventive repairs conditioned by time and emergency repairs. In addition, the article describes the classification of bearing damage according to ISO standards, which identified the mechanisms related to the formation of any type of damage.

In the course of homogenizing annealing of aluminium alloys being cast continually or semi-continually it appears that chemical in homogeneity takes off within separate dendritic cells (crystal segregation). It is about a diffusional process that takes place at the temperature which approaches the liquid temperature of the material. In that process the transition of soluble intermetallic compounds and eutectic to solid solution occurs and it suppresses crystal segregation significantly. Temperature, homogenization time, the size of dendritic cells and diffusion length influence homogenizing process. The article explores the optimization of homogenizing process in terms of its time and homogenizing annealing temperature which influence mechanical properties of AlZn5,5Mg2,5Cu1,5 alloy.

In micro cutting it is necessary to control the cutting tool. Monitoring of cutting tools is usually accomplished by measuring cutting forces. In order to improve the accuracy of monitoring it is required to consider the ploughing forces. The ploughing forces substantially depend on the processing materials. This article describes the investigation of the effect of processing materials on the ploughing force values. The extrapolation method on zero cut chip thickness was used to determine the ploughing forces. The experiments were performed by cutting of aluminum alloys, structural steels, bronzes and stainless steels.

Metallic charge heating before rolling process is very important stage of technological process of bars rolling in continuous rolling mills. Achieve of requires metallic charge temperature and permissible temperature difference on its length depends on metallic charge heating method and using of heating furnace. Main reason of form a big temperature differences on the metallic charge length in case of walking beam furnaces is disturbance their correctly work through seal wear between constant and moving elements of furnace hearth. The paper presents results of experimental investigation the non-uniform temperature distribution on the metallic charge length during round bars rolling. Thermovision monitoring were carried out during 70mm-diameter plain round bars rolling process in continuous shape mill D370 in one of industrial plant. Constructional steel S355J2G3 (according to DIN St 52-3) was used for the research. For the temperature measurement the ThermCAM SC640 thermovision camera was used.

This article deals with dry turning of nickel superalloy - Inconel 718. The different ceramic inserts were applied for cutting process. These inserts were produced by Greenleaf Corporation company. This paper discusses durability of cutting inserts, the different intensity of tool wear at various cutting parameters. The most suitable cutting conditions are chosen in the scope of applied tools.

An agricultural machine construction is exposed to significant effects of functional areas wearing. The application of polymeric materials and composite materials seems to be prospective. The abrasive wear resistance was tested on rotating cylindrical drum device with the abrasive cloth of the grain size P120. Various modifications of polymeric particle composites, Polyethylene and Polyamide 6 were tested. The polymeric particle composites research and production were focused on knowing the dependence among a two-component epoxy adhesive and various concentration and fraction of corundum hardening particles Al2O3. Polymeric particle composites showed a potential possibility to resist to high abrasive wear (evaluated decreases in volume) when applying the hardening phase of the grain sizes F80 and F240 and the concentration no exceeding 45%. They showed a low density ρ 1.20 till 2.00 g.cm-3 comparing the steel (ρ = 7.75 g.cm-3).

When selecting the optional parameters in machining inner cylindrical surfaces the diameter of a borehole cannot be ignored. Also in finish precision machining, when fulfilling strict accuracy and surface quality parameters economically, it was presumed that the size of the borehole diameter has got an effect on the machining times of different procedures. Five different hard machining methods are compared here on the basis of time consumption. The common characteristic feature of the comparative investigations of different hard machining procedures is that their benchmark is always the traditional grinding. This time, too, that has been chosen. It is presented how the borehole diameter influences the machining times and the most economical procedure is proposed to be selected for given borehole diameter.

This contribution deals with the need of continual experimental study of the phenomenon that relates to the increasing demands to the quality of engineering production and also to the productivity and economy of the production. Experimental part is focused to the influence of the tool coatings, which significantly affect the roughness of the material machined with the use of the cutting plates made of high-speed cutting steel. The plates were used in the series of the experiments, what allows us to create the models of real situations in the area of concrete manufacturing technology and subsequently to analyze them. To the measured and evaluated parameters belonged: the roughness of the machined material after the use of coated and uncoated tools. Planing technology is realized until there are major visible changes in cross roughness of the machined material, what means the increasing of Rz values. This is caused by the fact, that the coating was removed from the cutting edge, what is considered as the blunting of the tool. Measured values are statistically expressed in the form of the graphs.

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

Hot-dip galvanizing is one of the most widely used method for protecting of structural steels against corrosion. In general galvanizing process dross called as "hard zinc" is formed on the bottom of the zinc bath. It is formed by the reactions between molten zinc and iron particles in the galvanizing kettle. Hard zinc represents valuable secondary raw material because of the high content of metallic zinc (94-97%). Bottom dross, being an alloy of zinc and intermetallic phase crystals containing 3-6% wt. Fe, has no direct use in the galvanizing process. For this reason there are attempts to elaborate the technology of obtaining a refined zinc containing less then 0,05% wt. Fe. Hard zinc refining with aluminium is one of the method for iron removing. Refining process is based on the formation of intermetallic particles of AlxFey type. Refining of hard zinc through removal of iron has been investigated in this study. The effect of various aluminium additions as a refining agent has been studied. Light microscopy and AAS (Atomic absorption spectroscopy) have been used in the evaluation of the refining process.

This article deals with grinding of the hardened and tempered steel in different coolants. The G-ratio is one of the important parameters of grinding process and shows efficiency of this. The development of machining technologies is still moving forward, there are new materials and types of tool using in production and manufacturing. With a new materials usage we want better parameters of process, e. g. higher G-ratio, lower heat balance and better surface quality after machining. New types of abrasive grains that we used are based on Al2O3 - microcrystalline corundum and parameter of G-ratio and surface quality after grinding will be described in this article. For experiment were chosen three types of coolants and one of grinding wheel. We can see changes of G-ratio and surface quality during grinding at different coolants.

The traditional approach to grinding is to operate within the limits of surface quality. The requirements for surface quality in grinding are higher than those in other common machining operations such as turning and milling. The surface quality of machined parts is very important for precise production and assembly. When we focus on roughness parameters after grinding, we can establish the limits of these parameters for typical grain materials: Al2O3, SiC, CBN, SG and others. Increasing demands on accuracy and quality of production leads to research concerned with the properties of these materials and the surface quality after grinding. This paper shows new possibilities for the ground surface with focus on surface roughness obtained under varying combinations of cutting conditions. The influence of the grinding wheel, cutting parameters and coolant on higher surface quality is assessed by roughness parameters Ra, Rz, Rt and the Material portion of a surface profile. These high-precision ground surfaces are shown to have a Nanometres (10-9) unit topography demonstrating that the process is able to replace other finishing technologies such as superfinishing or honing.

Introduction into problems - The aim of the paper was microscopically analyze protective layer by coated sheets after corrosion loading which were pre-treated by various ways. The samples were divided into 4 groups according to the pretreatment type and duration of corrosion load. After a corrosive effect on the corrosion chamber the protective layer was subjected to microscopic evaluation. For samples of group I and IV have to degrade the protective layer and the formation of corrosion products on the base material which causes degradation of the protective layer and shorten its life. For samples of group II and III microstructural analysis showed good condition of the painted surface layer and the base material showed no presence of corrosion products. It again confirms the need for compliance of technological conditions for the pretreatment of the surface particularly in the application of modern less aggressive means.

The research focuses on verification of FEM simulation of GMAW bead on plate welding with experimental results. In the program Visual Environment simple FEM simulation of GMAW bead on plate welding on Al alloy EN AW 7022 was created and these simulation data were compared with measured experimental data. To create good FEM model setting of heat source and material parameters are of great importance. To set parameters of heat source measurement of welding parameters, metallographic sample, weld bead and end crater was experimentally done. During experiment, temperature was measured by several thermocouples and measured temperature was compared with simulation data. The difference of measured and simulated data was at maximum only 10°C and we can conclude that this result is very good. Simulations that obtain results close to reality are very useful for designing welded constructions. Designing from using precipitation hardenable Al alloys, e.g. series 7xxx, materials prone to softening, when welded, can be thus made easier and safer using simulation software.

The article presents problems with commercial inverter source Rapid Arc application on fillet and V-grooved welds. Principal and conditions of the process are explained and especially restriction due to source and feeder upper power limit is described. Case study of "weld design for fabrication" method was demonstrated, where type of weld and shape of groove is designed on the base of experimental results of process penetration behavior at 1/2 V-groove joint. Results are described and discussed, using special welding parameters monitoring equipment and software. A change of metal transfer behavior was recorded in accordance with torch angle setting and originally explained.

Experiments described in this paper determine two body abrasion of two- and three-phase polymeric particle composites with a different size of filler particles. An epoxy resin was the matrix of composite systems, corundum and chips of iron metals represented the filler created from secondary raw materials. The results show clear influencing of composite hardness and abrasive wear resistance caused by the fillers. The influence of the size of bonded abrasive particles on the wear of the composites based on the waste was proved and it is noticeable - with tested abrasive clothes it is 65 times.

In evaluating larger number of measurement data, it is proper to analyze them statistically. It is important to determine the effect of measured data number on the experiment results. This paper is focused on the determination of the effect of the basic file size (data obtained in the experiment) on the final measurement results. In milling the cutting inserts of sintered carbide (SC) were used. The same cutting conditions (depth of cut, feed, cutting speed) and were used. The cutting inserts wear was measured after the same cutting time. At the beginning of experiment 120 measured data (edges) were used. Number of measured data was gradually increased (to 240, 360, 480, 600, 720, 840, 960 and 1080). Totally 9 basic files was obtained. In the conclusion of the paper lists of all results are presented together, with their mutual comparison and prediction of the possible development of tool wear at higher number of cutting edges.

In 1906 Taylor mathematically defined the dependance of tool durability on cutting speed in the form: T=CT/vm for the first time. It is an equation of a hyperbola, which represents itself as a straight line in double logarithmic net according to Taylor. The dependance is valid for the tools made of high-speed steel. It has still been used in spite of the fact that new cutting materials, which cannot be used according to it, or can be used only partially in a narrow range of higher cutting speeds. The course of function T=f(vc) for the tools made of sintered carbid and ceramics will be identified in the paper. It requires extensive durability tests in a wide range of cutting speed. Interesting conclusions can be derived from its course.

Precision machining and especially hard machining is a topic of high interest at present. Surface integrity requirements increase. Hard precision machining may substitute some abrasive operations. There are some advantages of hard cutting over the abrasive machining. Abrasive machining has traditionally performed the finishing process of hardened steel. But, the availability of hard and super hard cutting tools enable the machine tools to reach surface quality of hard machining like to those obtained in grinding processes. A surface is not only a geometric entity but also a layer with its own structure and properties. These properties are affected by many factors, e. g. by cutting temperatures, friction, deformations in the primary deformation zone and the surface layer of the transient (machined) surface, by cutting tool geometry, work hardening, cutting environment, etc.

The paper presents utilization of class ERP system for examination, analysis and updating of production standards. The investigation has been performed in a medium size enterprise manufacturing products of steel strip and sheet. It has been shown that everyday reporting of production in the ERP class system makes it possible to examine the individual products in respect of the production time and becomes a basis of verification of the standards imposed by the master firm. Continuation of the reexamination after verification of standards will most probably initiate introduction of piecework wage system.

This paper reports on the outcomes of a study concerned with the mechanical properties of a new abrasive tool manufactured wholly from thermally treated recycled glass. These properties will aid in understanding the behaviour and performance of the treated glass. Mechanical properties were investigated using the most current and advanced nano-indentation methods. A computer controlled Nano Indentation hardness test (NHT) machine was used to obtain values of hardness and elastic modulus. The nano-indentation process was equipped as a FEM parametric model. The model was then processed by purposely developed numerical objective optimization algorithms in order to determine comprehensive material properties. The aim was to establish the optimal solution with reference to mean square root optimization criterion. The results show large elastic recovery upon unloading similar to a pure silica reference material and a surface roughness unique to this material which is entirely crystalline. The indentation mapping shows significant effect of heat treatment cycles on mechanical properties of recycled glass media.

Composites are materials which combine properties of two and more phases and create entirely new material. In case of the polymeric particle composites one phase - a matrix is represented by the polymeric material most often in a form of an epoxy resin and the second phase - a filler is composed of inorganic particles. The paper deals with the polymeric particle composites whose matrix is composed of the epoxy and polyester resin with a high concentration of a waste corundum (Al2O3) particles. The paper focuses on chosen mechanical qualities of these materials: an abrasive wear resistance and an impact strength. Increased portion of the filler in the matrix predetermines these systems to considerable abrasive wear resistance. This hypothesis was confirmed by carried out experiments when the volume loss decrease of the composite systems with the matrix saturated with the particle filler reached values 0.04 cm3 whereas the volume decrease loss of the epoxy resin without the filler reached 0.56 cm3. The maximum applied saturation of the matrix with the particle filler was reached at the polyester resin when this value corresponded to 50 volume percentages.

The paper presents a concept of the design of gear shaper cutters with curvilinear side flank faces. The problem of forming the outline of the cutting edge of the gear shaper wedge has been discussed and the possibilities of execution of this type of knives have been indicated. The method of forming the rake face of curvilinear side flank face has been presented.

The aim of this experiment was to melt down aluminium beverage containers and making use of the recycling process to acquire an aluminium material of a certain chemical composition for another production process with the aim of manufacturing aluminium semi-products and products. The aluminium material extracted in this way was subsequently analysed chemically and metallographically. These experiments were carried out within three casts and in all three cases the batch was formed by 100% of aluminium scrap in the form of finely shredded aluminium cans (Fig.1) and from the point of view of the complex efficiency assessment of the recycling process a calculation of the yield of the acquired aluminium alloy was undertaken. At the same time, considering that the aluminium waste was coated with plastic materials, paper and varnish/lacquer, it was necessary to identify the content and compositions of the substances released in the course of the melting process in the form of gas and assess their possible negative impact on the environment.

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