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This paper describes the material use of EFB biomass in the form of composite systems. It describes the tensile characteristics, hardness and wear resistance of polymeric disordered composites epoxy/EFB prepared by vacuum infusion. Electron microscopy was used to describe cellulose EFB fibers and their microstructures. The paper deals with a very simple material when the fibers were not separated from the EFB biomass - EFB biomass was used as it is produced by the processing line. The experiment describes composites with untreated EFB biomass and EFB biomass treated chemically with alkali - 6% aqueous NaOH. Due to the residue of the seed shells and clumps/fiber additions, the cracks initiate and the tensile characteristics decrease up to 46%. Although there have been no significant increases in observed characteristics, this material has some potential in terms of design or in the form of insulating material. The resulting properties could be enhanced by chemical treatment of the fibers, separation of fibers from the residues of the fruit and preferred fiber orientation.

The paper deals with a design of required electric motor power for the conveyor line. This machine will serve for automatic soldering of a compressor outlet piping in a real company. The calculation of the motor is necessary to ensure a required handling of pallets with the compressors, i.e. between individual working positions. These positions consist of manual loading components on the line, automatic soldering and manual tightness control. After determining the power of the drive motor, it will be possible to produce a real prototype. The designed electric motor will be integrated into the machine and that will demonstrate the correctness of all design suggestions and calculations including the dimensional calculation of the drive motor in conjunction with the customer's technical standards requirements.

The present work deals with the execution of through micro-holes on tungsten carbide plates using a micro-EDM (Electrical Discharge Machining) machine. The investigation focuses on the monitoring of the performance during the drilling phase in order to obtain the in progress behavior of the performance indexes. The experiments were carried out by varying some process parameters such as peak current, voltage and frequency to achieve both high and low power discharge conditions. Regarding electrodes, the most commonly industrial used ones were selected: tubular tungsten carbide and brass. The performance indexes taken into account were machining time, Material Removal Rate (MRR), Tool Wear (TW) and Tool Wear Ratio (TWR). Brass electrode always resulted to be the best solution in terms of drilling speed even though the wear of this electrode type is remarkable higher than the tungsten one. The evolution of the performance indexes during the drilling operation showed the same trend for both electrodes: increasing the hole depth, the drilling operation proceeds in a more difficult way, due to the evacuation of debris that becomes more difficult and therefore the performance indexes get worse. Finally, the technology windows of the cumulated MRR and TWR were defined for both electrode materials, in order to predict the micro EDM process performance varying the hole depth.

The paper deals with a machining of polymeric composite materials reinforced with fibres from hemp, false banana (Ensete ventricosum) and microparticles from Jatropha Curcas L. seedcakes by means of a technology using a water jet (abrasive water jet AWJ, water jet WJ). A matrix of the composite material is from a structural resin used for a production of sport equipment which shows good mechanical properties, but is it very brittle and it comes to its destruction during machining. Therefore, the water jet technology was used for the research. The research was focused on the evaluation of an influence of a velocity of a cutting head movement on a kerf width inlet and outlet the composite board by means of an optical analysis and on a connected quality of the cut. The composite material based on the biological reinforcement was cut by CNS cutting machine AWJ CT 0806 at a different velocity of the cutting head movement (traverse speed), i.e. 50, 250, 750 and 1000 mm/min. The research results proved a significant difference between the technologies AWJ and WJ and also among the velocities of the cutting head movement. The cut was inhomogeneous under unsuitable conditions and it came to a significant destruction of a surface outlet of the water jet.

Within the context and term of quality it can be comprehended as a subjective character. Every individual has its own requirements, expectations or standards on specific product or service. Thus, these parameters are then connected and defined by different priorities. Many of the customers are willing to pay more money for increased quality of bought product however many of them are forced to decrease their requirements due to the costs and they have to be satisfied by products with lower quality or lesser amount of defined parameters. The main aim of the paper is to observe and analysis of cost system and its effect on product quality through the monitoring, analysis and evaluation of production costs in selected organization. Due to the comprehensive evaluation of the effects of investments on the resulting quality in selected organization a various methods was employed. Among used methods was comparison of investments into production quality by data analysis according to PAF model, mathematics and statistical parameters and Pareto's analysis. There were suggested individual steps by utilization which allows determining, evaluating and creating an individual system of observation and evaluation. Such a system of costs analysis is then suitable for selected companybut not limited to it. The utilization of such a system is therefore applicable at any company or organization which is focused on custom small-series production.

The requirement for high strength and ductility is usually associated with martensitic microstructure with a certain amount of retained austenite. One of the innovative heat treatment processes that can lead to such microstructure is the Q&P process (Quenching and Partitioning). It can produce microstructures consisting of martensite and a certain amount of retained austenite, which exhibit strengths above 2000 MPa and elongation levels of more than 10%. The objective of this research was to explore the effects of the cooling rate in the Q&P process and evaluate the effects of various microstructure constituents on mechanical properties of high-strength steels. Three newly-created experimental steels, which contained 0.43% carbon and had reduced Ms temperatures thanks to manganese addition, were subjected to several heat treatment routes which involved various cooling rates. The cooling rates were chosen on the basis of calculations using the JMatPro software and earlier results. It was found that by varying the cooling rate one can obtain various mixed microstructures and a wide range of mechanical properties. The strengths were in the range of 1200-2300 MPa and A5mm elongation levels were up to 18%. Because the amount of retained austenite has a considerable impact on the resulting mechanical properties, it was measured by means of X-ray diffraction.

This constribution presents the engineering design of the non-conventional shearing device, which uses for the operation the magnetic field. There is a prototype of the device designed and constructed in laboratory conditions. There are presented all relevant and necessary data of this shearing device supported by figures and scheme. The principle of the device operation consists in the fact that a sheet passes through feed rollers into the shearing position, i.e. into the position between two blades. Lower is fixed and the upper is guided in rails and controlled by means of springs. After the material dividing the electric circuit is interrupted and the moving blade returns into the starting position due to spring's action. This process of metal shearing can be quite simply automated. We have performed same experimental works using this device. There were sheared same sheet samples and the comparision of surfaces are shown. The use of our our device has proven to be appropriate for shearing sheets made of aluminium alloys with the thickness of 0.3 mm.

Additive manufacturing (AM) allows printing from different materials: from wax to plastic and even metal. This paper concentrates on Direct Metal Laser Sintering (DMLS), which allows printing to create complex parts from different kinds of metal. Inconel 718 was chosen for this research. This material is used especially in the aerospace industry and in other demanding applications due to its characteristic properties, which include high strength at high temperatures, corrosion resistance, low thermal conductivity, high hardness, work hardening and low thermal conductivity. Components used in aeroplanes must be very reliable, lightweight and their mechanical stresses must be accurately described, because the components are designed with respect to these criteria. For this reason, each material must be perfectly described in terms of mechanical properties and their minimum limits must be identified. Tensile testing is the best way to find the basic set of mechanical properties of a material. The samples were printed in two different orientations on a building platform and the differences in mechanical properties were investigated. The effect of machining on mechanical properties was also investigated.

The abrasive wear of pulley surfaces at winding of the ropes causes changes of the shape and quality surface of the groove and has influenced lifetime of the skidding machine. The pulley is made of steel C45E without heat treatment and its structure is not suitable for the abrasive wear of the pair metal-metal. Contribution describes a research aimed to changes in material structure by the heat treatment. The pulleys (first one in original state and second one after heat treatment) were tested in operating load at skidding during 320 hours. After experimental test, measurable properties as weight loss, groove dimensions of the pulleys were compared. On the samples from the pulleys, material resistence to wear was tested too. Another alternative for change of material properties would be an aplication of various types of weld deposits on the steel C45E. We have examined the quality of weld deposits and compared their hardness and microstructure. The results of experimental tests resulted to recommendations for practice.

The article describes the possibilities of pre-treatment of hot-dip galvanized parts and their influence on the adhesion of organic coating. The main objective of this work was to compare the current possibilities of pre-treatment of hot-dip galvanized parts, this means phosphating, chromating and mechanical pre-treatment by light blasting and compare these technologies with today's alternative pre-treatment technologies based on chemical substances containing fluorozirconates. The basic function of these pre-treatments is to increase the adhesion of the organic coatings and to increase the lifetime of the entire corrosion protection. Another objective is to reduce the environmental impact of these pre-treatments, reduce energy for the technological process of pre-treatment and many other aspects. Last but no least to compare the different types of organic coating systems with using these pre-treatments on the hot-dip galvanized surface.

This paper deals with the preparation, composition and mechanical resistance of inorganic-organic nanolayers with built-in hydrophobic groups through sol-gel synthesis. The components of the nanolayers are 3-(trimethoxysilyl)propyl methacrylate, tetraethyl orthosilicate and hydrophobic chains - hydrocarbon chains in the range of 8 to 16 carbons. The study is aimed at evaluating the mechanical properties of prepared nanolayers with different hydrophobic chains compared to a reference sample without any hydrophobic groups. An abrasion resistance test was performed on several selected nanolayers with the best hydrophobic and antifouling properties. In the framework of the research, nanolayers prepared with polymerization achieved by heating at 85 °C or 150 °C were compared. The best mechanical properties and hydrophobicity of prepared nanolayers was AF12 with a hexadecyl hydrocarbon chain polymerized at 150 °C. These nanolayers are suitable for marine, underwater or any other hydrophobic application results from performed research.

When a micro-hole of high aspect-ratio is required, in addition to machining problems, special attention should be paid to controlling the quality of the manufactured products. Dimensional and surface metrology in the field of micromachining can be as critical as machining itself, therefore several new measurement methods have been developed. However, many of these methods suffer from application limits when used in the case of a deep hole. Replication can be a useful approach, which has well-proven validity in the time-consuming case of the sectioned hole. The method of through replicas, to be pulled out of the unsectioned hole, still needs verification.
In the present paper, the surface roughness of deep small electrodischarge drilled holes is measured, and the effectiveness of the use of both open- and through-replicas is evaluated, versus direct measurements on the micro-drilled surfaces. Through-hole replicas, by means of injection and extraction of a silicone, are proven reliable for reproducing the surface morphology of holes down to 0.8 mm diameter with an aspect ratio of 12.5. The findings show that the operative range of the considered techniques may be extended with respect to the previous cases mentioned in literature

The aim of this article is to calculate and compare the modal properties of the frame of the standard and modified freight wagon bogie design. Analysed frames represent the main support parts of the bogie, which are most often used in the Central Europe region. Determination of the modal properties belongs to the fundamental but very important step in the engineering design. In our case, modal analyses of bogie frames structures were carried out using the Finite Element Method. In order to perform numerical calculations based on FEM approach, Ansys package was used. Modal analyses of individual parts as well as substructures of rail vehicles is an inseparable part of the rail vehicles design process. In this article theoretical and practical consequences of obtained results from the modal analysis, i.e. eigenmodes and eigenfrequences of the analysed part of the bogie on its dynamic properties are presented.

Special attention is taking place in the environment of public transport, for which higher amount of small radius curves being applied is specific. The outcome of such operation of vehicles is an increase in vehicle's effects on the track in the rail-wheel contact resulting in increased ride resistance, creep in the rail-wheel contact patch, speeding up the process of wear in the contact pair as well as noise generation. At present, a variety of technical solutions for the vehicle bogie design as well as track designs focused on decreasing of these negative effects exists. Their use in smaller radius curves however, cannot give acceptable results and often causes complications in bogie design. The authors give a concept of creep reduction in rail-wheel contact by using double wheel tread, which doesn't require complicated bogie design. The proposed solution is supported by dynamical simulation of the tram car vehicle ride with considering of active wheel tread changes, and is also registered under Patent Application Nr. a201701589.

In this paper, the results of an investigation done with face milling are presented. The changes in cutting force and surface roughness were studied through changing the values of depth of cut and the feed per tooth. Meanwhile the permanent value of the undeformed chip cross section, which was determined (fz and ap), remained permanent. Increasing fz and keeping the same value of Ac chip cross section, the ratio ap/fz changed in five grades from 0.5 to 8. It is shown, that if the feed is increased in the examined range so that the chip cross section is constant, then the value of the cutting force decreases, which decrease can be observed in all three force components. Accordingly, the mechanical power required for cutting is reduced. The results of the surface roughness investigations showed that initially a significant increase can be observed in the roughness with the gradual increase of the feed (up to ap/fz = 2.5), followed by a moderate increase afterwards.

Using of cutting inserts is currently a normal part of the manufacturing process. The article deals with analysis of tool wear after machining at one selected cutting insert. Evaluation of this insert was made by electron microscopy. There was used SEM and EDS analysis. For this purpose was used scanning electron microscope Tescan Vega 3 and EDS analyzer Bruker 16 which is part of this microscope. These analysis can provide a good picture of the structure and construction of inserts, their composition and for situation on the insert after machining. This may assist in finding suitable cutting conditions. As experimental material the hardened steel class 16MnCr5 according to EN 10027-1 has been machining. SEM images of final tool wear of the cutting insert were recorded. The reason was to map the tool wear state after machining using electron microscopy to give a better view of the situation. These analyzes were performed in other experiments performed at the Faculty of Mechanical Engineering at Jan Evangelista Purkyně University in Ústí nad Labem.

The paper deals with the proposal for the production of an assistance brake for a mechanical wheelchair, which will help the wheelchair users to move in the course of overcoming barrier-free and partially barrier obstacles. The introductory part of the contribution characterizes the basic requirements of the brake for a mechanical wheelchair, especially from a legal point of view and in terms of their safety. The practical part of the paper deals with the production of a prototype pair of assistance brakes in school conditions (workshop C2 of the Institute of Mechanical Engineering, Faculty of Mechanical Engineering, Brno University of Technology) using conventional machining technology (brake body production) and 3D printing technology (braking segment production). Part of the practical part also requires testing in typical / real wheelchair conditions. The contribution is completed by the technical and economic evaluation of the prototype pair of assistance brakes, which is related to the calculation of the total cost of their production.

With increasing complexity of machinery and products manufacturing the strict requirements for quality and, reliability of the measurement equipment and systems plays significant role in production system and quality assurance in terms of customer satisfaction. In nowadays automotive industry in connection to ISO/TS 16949:2009 there has been observed a strong confrontation with request for proof of suitability for use of selected gauges for a specific operations. An appropriate methodology allowing to determine a gauge the most suitable for a given operation is Gauge Reproducibility and Repeatability study (GRR or R&R). The GRR takes into a consideration the variability of produced parts, operator`s approach, and whole measurement system. The article deals with a description and the adequate methodology, and the experimental implementation of GRR in manufacturing quality process assurance in order to set up and continuously improve the quality level in automotive parts production.

Article focuses on the monitoring of motor wear of vehicles powered by a dual-fuel diesel-vegetable oil system. The introductory part focuses on the use of biofuels for combustion engines and tribotechnical diagnostics for wear testing. Analysis of engine oil samples from vehicles with different fuels is carried out. Fuel is diesel fuel, biodiesel and a two-fuel system with two fuels - rapeseed oil and diesel fuel. The abrasion wear of biodiesel is increased. Wear in dual fuel system is within the standard exchange interval in the zone of emergency wear of metallic particles and carbon. The article evaluates the adjustment of the oil exchange interval to limit negative effects on wear surfaces. Shortening the interval to the optimum level for biodiesel is 1/3, for dual fuel system is 1/2. Vegetable oil in engine oil causes a change in the character of lubrication. Shortening the interval to 1/2 is necessary to minimize negative effects.

Customer requirements represent the driving force in the market, dictating the directions of development, production and processing of forged parts. Meeting these requirements is of paramount importance to forge shops as a precondition for their continuing operation and competitiveness. Consequently, optimization of manufacturing operations and their rapid response to market requirements are necessary for the forge shops to survive. However, any production stoppage for optimization results in extra costs. Forge shops thus strive to carry out optimization in as few steps as possible and within the shortest possible timeframe. A viable solution emerges in the form of material-technological modelling which involves laboratory-based optimization taking place away from the forge shop without any constraints on the production operations. This paper deals with selection of a material for a forged part to be controlled-cooled from the finishing temperature to substitute a C45-steel part treated by normalizing. One criterion was that the entire forged part should contain ferritic-pearlitic microstructure.

During the period of use, there are in the dental implants, the limit conditions of the primary structure and later on its disruption created. The aim of the work was to study microscopic defects in the proposed materials in which the unwanted defects arose and led to early end of the lifetime. It is a dental implant, which had to be prematurely taken from the oral cavity due to limit conditions of the patient pain.
Investigation of chemical elements of dental implant materials has shown the presence of such components, which lead to create undesirable intermediate phases in the structure and therefore the analysis of the implants has been complemented by microscopic evaluation.
There are on the part of the dental implant, which interacts with a bone of a patient, the corrosion destruction of the material was visually observed. For this reason, the character and thickness of oxide layer, that negatively affects the living cells of the organism, was also examined on more detail.

This article describes the formation of a composite coating in a polymer matrix on an aluminum alloy. It is a PMMA coating (polymethylmethacrylate) with the addition of TiO2 particles. Working with these particles requires not only safety but also a suitable preparation process to obtain particles of suitable size, their subsequent homogeneous distribution in the coating (particles of this size are influenced by electrostatically attractive forces and have a strong tendency to aggravate). The first part describes the material used, sample preparation and coating process, surface roughness measurement, SEM and EDS analysis of selected samples. The aim of the research is to find out whether it is possible to use dipping and brushing techniques when coating Al-Si alloys with polymeric materials. Consequently, what can be achieved is the roughness of the surface of the coated part compared to the uncoated surface (at different particle concentrations in the spin) and the distribution of TiO2 particles on the surface of the sample.

Surface roughness is one of the most significant evaluation factor in metal machining operations. Despite the small descriptiveness is usually quantified as the arithmetical mean roughness Ra especially in the automotive industry. In order to maintain the desired surface roughness, the appropriate setting of machining parameters is important to be set before the actual cutting process. The objective of this research is to analyse the effect of machining parameters on surface roughness of stainless steel X153CrMoV12-1 in CNC milling of slope surfaces with sintered carbide tool. The data were processed using multiparametric statistical methods to find optimal results. Linear regression models and probability dendrograms of similarities were determined for cutting conditions, cutting tools and slope of machined surfaces.

In the article the issue of perspective running parts for freight cars of new generation is considered and additions to the outdated existing classification of bogie are developed, namely introduction of such types of suspension is suggested.The results of theoretical studies are presented by means of modeling the movement of the car in the software "Universal Mechanism" to determine the influence of the first stage of spring suspension in Barber type bogie (type 18-100 and analogues) on energy efficiency (resistance to movement) and the estimated value of the decrease in resistance to movement.A concept for a fundamentally new design of a freight car bogie for high-speed traffic has been prepared, based on fundamentally new technical solutions with elastic-dissipative bearing elements, as well as a concept for the modernization of the Barber-type bogie (type 18-100 and analogues) by introducing axle suspension on the 1520 mm gauge.

This article deals with the issue of mathematical calculating the trajectory of the end-effector of an industrial robot in the manufacture of aerospace composites. Robots are used to define the winding orientation of the fibre strands on a non-bearing 3D core. The 3D core is attached to the robot-end-effector and is led through a fibre-processing head according to a suitably defined robot trajectory during winding of the fibre on the core. The quality of the composite depends greatly on the correct winding angles of the fibres on the frame and on the homogeneity of the individual winding layers. The implementation of these two conditions is related to determining the correct trajectory of the industrial robot, which is part of the composite production technology. The numerical modelling of a passage of the on-bearing 3D core through a fibre-processing head is described in the article. Differential evolution algorithm and matrix calculus are applied to the numerical calculation of optimized robot-end-effector trajectory to achieve optimal angles of windings of fibres on the frame. The numerical calculations of the trajectory of the robot-end-effector were used for verified for the calculated trajectory of the robot-end-effector in the real conditions of robotic laboratory of department of machinery construction.

Metalworking fluid (MWF) aerosols are generated continuously during conventional machining operations and can have a number of adverse health effects. Exposure to the aerosols has often been reported to cause acute respiratory difficulties including asthma, hypersensitive pneumonitis and lung cancer. Aerosol measurement data was conducted to identify the major determinants that may affect exposure to aerosol fractions during turning of a cylindrical work piece on an uncovered conventional lathe. The aerosol mass concentration was investigated as function of spindle speed, fluid flow rate and sampling position. Synthetic fluid, mixed at 5% concentration with water, was applied via nozzle centred above the work piece at a distance of 70 mm. The aerosol mass concentration was determined gravimetrically and particle size analysis was performed by optical method. The results show that aerosol mass concentration increases with increasing the fluid flow rate and decreases by increasing the spindle speed. Moreover, the particle size analysis detected that a high quantity of particles smaller than 0.2 mm is generated at higher spindle speeds.

The structural content of castings and non-conformities that might occur in pressure die casting is mainly connected with technological parameters. Analysis of the casting structure helps identify a group of causes of non-conformities which are connected with improper choice of technological parameters. The non-conformities identified in the pressure die castings discussed in the paper were analysed by means of metallographic examinations. A electron scanning microscope was used in the study for the analysis of the structure of casts. This analysis allowed for identification of the causes of e.g. shrinkage depressions or misruns. The analysis of the structure of a casting in the location of the depression revealed insufficient cooling time used for this casting.

Cutter vibration characteristics of five-axis milling machine in high-speed milling process were studied. Finite Element Modal Analysis for high-speed cutters with different parameters is conducted using finite element software.The impact of tooth number, extended length, diameter and material of milling cutter on the mode shapes and natural frequencies of milling cutter is researched in detail. Harmonic response curves of High-speed cutter under different frequency are calculated. Based on the response curve, the resonance frequency range of high-speed cutter is obtained in order to achieve high-precision milling and longer life of the tool. Analysis shows that: mode shapes of milling cutter are divided into strong vibration mode shapes and weak vibration mode shapes and its natural frequency become smaller with the increase of the cutter teeth number. Natural frequency of milling cutter decreases with the increase of extended length of milling cutter. The number of strong vibration mode is smaller with the increase of milling cutter diameter so that the milling cutter with large diameter can play a role of anti-vibration. Natural frequency of the high-speed steel cutter is lower than that of the diamond and carbide cutter. This research provides theoretical basis for the design of high speed milling cutter and reducing milling chatter.

Light reflection of materials depends on many factors, mainly on their colour and type, angle of light incidence and surface structure. This paper is focused on evaluation of the surface shape influence of expanded polyvinylchloride on light reflection. For this reason polyvinylchloride samples with different shapes, depths, widths and numbers of surface grooves were produced on CNC milling machine. The light reflection of the investigated material samples was experimentally measured by means of illuminance ratio. The samples were subsequently compared in terms of their ability to reflect light. A part of the work deals with mathematical simulation of the daylight factor for definite surface shapes. The simulations were performed using Wdls 4.1 software. It was found that the surface shape has an influence on the light reflection and on the illuminance in a given point too. The light reflection of the tested material is in general influenced by shape, depth, width and number of surface unevenesses.

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