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It is relatively complicated to effectively burn biomass. Combustion of biomass fuel itself as a renewable energy source does not automatically ensure the best use of its energy content with low emission production. Biomass combustion with bad settings of combustion conditions can be ineffective and with a high production of emissions. The article discusses the impact of humidity on the thermal technical parameters of the heat source. The influence of the relative humidity of combustion air and the fuel moisture on thermal power and emission production in automatic boiler for combustion of wood pellets were specifically determined. The results show that these properties of combustion air and biofuel have an effect on the thermal and emission parameters of biomass heat source. Biofuel moisture had higher impact on thermal power and emissions production in comparison with relative humidity of combustion air impact.

Quality of high-pressure castings is influenced by many factors. Structure and mechanical properties of these castings are mostly influenced by properties of casted material, technological parameters and thermal conditions in die casting mould. Thermal conditions in system casting - die casting mould is ensured by tempering system. However there is problem with thin cores and thin protrusions of die casting mould which is not possible to keep on the optimal temperature during casting by commonly available methods. Thus there is overheating in these places. It leads to the porosity of casting and also to the unsufficinet treatment of critical places of moulds which causes the lowering of their service time. With regard to the increasing requires on the castings quality is in practice searching still new possibilities how to cool down these critical places. One of the possibilities is to ally cooling by liquid CO2 into such places. This paper deals with the monitoring liquid CO2 cooling effect that is applied into the die casting mould core.

Recently, demand for porous biodegradable load-bearing implants, called scaffolds, has been increasing. The interconnected porous structure allows transport of body fluids to healing tissue and ingrowth of new tissue into the implant. From the point of view of mechanical properties, magnesium based materials seem to be very promising for scaffold fabrication. Moreover, magnesium belongs to biodegradable and bioresorbable materials and magnesium ions support growth of bone tissue. In this study we prepared porous magnesium by powder metallurgy using ammonium bicarbonate as a space-holder material and focused on the influence of initial powder shape on sample microstructural, mechanical and corrosion characteristics. Based on obtained results we found out that the usage of spherical initial magnesium powder produced samples with more spherical pores in comparison with those of samples prepared from magnesium chips. Due to these microstructural differences samples prepared from spherical powder achieved higher values of mechanical characteristics.

The paper deals with material research of a bronze circle from the Hallstatt culture period. The structure of bronze was observed with an optical microscope and scanning electron microscope. The structure corresponds to wrought tin bronze after recrystallization annealing. One original repair of the crack in the material which was done by cast bronze, was determined. The bronze contains a big amount of sulphide inclusions, which are oriented in a direction of forming material. Chemical composition of the alloy and non-ferrous inclusions were determined by the EDS analyser and minority elements were determinated by the XRF spectrometer . The bronze contains 9 to 10 wt. % Sn with minority elements Pb, Ni and Fe. XRD and SEM were used in order to identify nonequilibrum Cu-Sn phases. The results were compared with EBSD analysis. The nonequilibrium phase Cu39Sn11 was reliably determined by EBSD analyser.

The most important aim of chemical pre-treatment is the removal of contaminants, corrosion products etc. from the material surface and obtaining such a basic material surface, which will provide sufficient corrosion resistance of the base material and suitable conditions for the adhesion of paints or other finish coatings to steel material. When selecting the method of chemical pre-treatment of the base material surface it should be considered whether the degree of preparation provides the required level of cleanliness of the surface and also the surface roughness and surface profile for the coating to be applied to the base material after chemical pre-treatment. The paper focuses on SEM and EDS analysis used in evaluation of chemical pre-treatment based on nanotechnology. These chemical pre-treatments are excluded on low carbon steel sheet. On the surface of low carbon steel sheet were excluded coatings of chemical pre-treatments (Fe phosphate, coating based on nanotechnology) and has been studied character of excluded layers on electron microscope.

Introduction into problems - An idea of recycling is related to the sustainable development concept, which enforces this process. One of the most often recycled material is aluminium. It is recovered primarily from used beverage cans. These cans are normally back on supermarket shelves as new beverage cans in 6-8 weeks. With a growing percentage of the cans made from aluminium, because of its lightweight qualities, this ensures a healthy market for aluminium can recycling. In the paper characteristics of aluminium and the process of its recycling are presented. Its recovery rate in Poland is shown. The analusis of possible use of preformed granules of aluminium scrap into liquid steel deoxidation was also conducted. The results of the research carried out in laboratory conditions clearly showed that the sample 4 from the third supplier, from the viewpoint of the cost of the technology used in steel deoxidation, is the least favourable.

The paper analyses the influence of the feed motion speed vf on the value of measured geometric errors of the four-axis vertical machining centre CNC FV-580A with the FANUC 0IMB numerical control system. The tests were conducted with LSP 30 Compact laser interferometer (by Lasertex). Examples of modern, laser diagnostic systems of numerically controlled CNC machine tools were characterised in the article. Self-tracking laser interferometer LaserTRACER, diagnostic appliance LaserTRACER-MT, laser interferometer with XL80 with environmental parameters' measuring module XC80 and with heat sensors along with XR20-W calibrator were presented. Measurement results and their analysis were presented graphically in the form of diagrams and tables. The conclusion section comprises the discussion of the results, summary and deduction.

During the application of recent relationships between cutting conditions and results of machining there occur unevenesses, which can lead to incorrect choice of cutting conditions in concrete conditions of machining of engineering parts. Equations used in practice and on the base of wide experimental analysis to optimise their shape are being analysed in the paper. It concerns the evaluation of chip compression, machined surface microgeometry and cutting tools durability.

This article is interested about drilling the holes to the alloy wheels. Tested were drills to drilling holes for screws and service holes. For screw holes was tested the three-stage drill with inserts from polycrystalline diamond. Drilled are two different diameters and the transition spherical or conical surface. The service holes were drilled with cemented carbide drill availible from Mapal labeled Mega-drill-Alu-180. During test, was modified the geometry of the drill and we watched what will be the effect of applied modification. Tested was seven variants of regrinding the drill. We evaluate the surface roughness, but also if the drill has the right position and not be pushed away from its axis. Finally was tested drill with three edges. This drill bit is from company Mapal labeled Tritan.

The paper puts forward structure design and parameter analysis of the multi-angle and stepping transmission device, and this paper focuses on design and analysis of the multi-angle steering parts in the device. According to mathematical calculation and simulation analysis, the parts size of steering component is simulated and designed by the double cam-linkage mechanism. Though the design of these critical components of the steering device, the rods can be rotated in the specified angle (45° and 90°) by their relative motion without any external force, and the steering device is simulated by SolidWorks Motion. The results show that the multi-angle and stepping transmission device realizes the upset forging process requirements, improves the mechanization level of the sucker rod forging. The device will be used for the rod head machining operation in narrow space in automatic production line, and it also can be extended to other cylindrical rod's multi-angle and multi-position automatic machining operation.

Some perspective materials are characterized by shape memory effect and NiTi alloy belongs to their main representatives. NiTi is an approximately equiatomic alloy of nickel and titanium and it possesses interesting properties, such as superelasticity, pseudoplasticity and good corrosion resistance. Hence, it is used in different branches of industry (aerospace, medicine, engineering etc.). Common manufacturing melting methods of this alloy are vacuum arc remelting (VAR) and vacuum induction melting (VIM) methods. However, these methods have some disadvantages. The VAR process must be repeated several times to achieve sufficient homogeneity of manufactured ingots. During the VIM process the melt can be contaminated by carbon originated from graphite crucible. Therefore, powder metallurgical methods have been extensively investigated in last years as an alternative to the common processes. In this work, NiTi samples were prepared by the thermale xplosion mode of self-propagating high-temperature synthesis (TE-SHS). Chemical and phase composition, as well as microstructure and hardness of the prepared samples were studied. Afterwards, the samples were heat treated and the influence of the annealing on the studied characteristics was investigated.

The presented article describes the unconventional technology - bending and forming by laser. This technology is alters the tension in the material, which subsequently change the shape of formed parts. Article also describes four mechanisms of deformation after the impact of the laser beam on the material: The first mechanism - mechanism of temperature gradient, the second mechanism - buckling mechanism, the third mechanism - pressing mechanism (Borten) and the fourth mechanism - mechanism of phase transition. The experimental part focuses on the metallographic evaluation of samples from three different areas of the laser micro forming. Article describes in detail the technological parameters used during the development of the experiment and includes a summary of results. Article contains images of the structures detected in the heat affected zone.

The modelling of dynamical systems with mutual interaction through normal and tangential forces between surfaces is one of the most important tasks in the current computational research. The paper deals with the formulation of the equations of motion in dynamics of multibody systems and subsequent usage of various contact force models. Four types of normal force calculations are introduced and their behaviour is demonstrated using a simple example of a sphere moving towards a plane. The parametric study of the contact models with respect to the coefficient of restitution and an exponential parameter is performed. In order to show a more practical usage the simplified dynamic model of a nuclear reactor control assembly is created and its dynamic response is discussed. The model is characterized as a falling rigid body in a narrow channel filled by a fluid.

The paper dealt with method of immediately cutting process stoppage, process of chip formation and the non-linear finite element analysis. To be able to follow the process of chip formation and machined surface during machining, it is necessary to stop this process immediately, if it is possible. The paper provides results of non-linear numerical experiment for presented method. The state of plastic deformation in machined material and in front of the tool cutting edge enables to follow the intensity of deformation, friction process between the tool, chip and workpiece, sources of heat in the machining zone. Knowing these processes enables to select optimal tool geometry, cutting conditions, mainly cutting speed, cutting environment, tool material so that cutting process could run with minimal energy consumption and required quality of machined surface could be reached. To understand the process of chip formation is important for the theory and practice of machining of materials.

This paper presents the theoretical and practical aspects of industrial robots transport systems problems focused on application possibilities connected with concrete type of robotic device. Introduction of the article presents today possibility of robot transport systems and collect information about basic technical parameters of transport systems, their design and construction. Main part describe industrial robot ABB IRB 140, collect information about technical parameters, its construction, axes, motions and applications used in industrial practice. Practical part of paper is focused on proposal of robot transport system design from manufacturing point of view.

Resistance welding ranks among progressive and in practice often used manufacturing techniques of rigid joints. It is applied in single-part production, short-run production as well as in mass production. The basis of this method is in the utilization of the Joulean heat, which arises at the passage of current through connected sheets at collective influence of compressive force. The aim of the carried out tests was the optimization of the resistance spot welding working variables, concretely the determination of the dependence between the rupture force of spot welds made using sheets of different thickness and different welding conditions. For carrying out of this aim 650 assemblies were prepared. The test specimens of dimensions 100 x 25 mm and thickness of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm and 3.0 mm were made from low carbon steel. In the place determined for welding the test specimens were corundum blasted and then degreased. The welding of two specimens always of the same thickness was carried out using the welding machine type BV 2,5.21. At this type the welding current value is constant (Imax = 6.4 kA). The welding time (the time of the passage of the current) was changed in the whole entirety, namely 0.10 s, 0.15 s, 0.20 s, 0.25 s, 0.3 s, 0.4 s, 0.6 s, 0.8 s, 1.0 s, 1.3 s, 1.6 s and 2.0 s. The compressive force was chosen according to the thickness of the connected sheets in the range from 0.5 to 2.4 kN. From the results of carried out tests it follows that using the working variables recommended by the producer we obtain the quality welds. But it we use the longer welding times, we can obtain stronger welds, namely of 5 to 35 % compared to welds made using working variables recommended by the producer.

Springback of v-type sheet metal must be controlled during the high precision forming process. While, variable blank-holder force technology is an effective measure to control sheet metal springback, but it only overall control the stampings. The project was put forward through the v-type sheet's variable blank-holder force and adjustable drawbead to control springback, which is place electric adjustable step drawbead around the blank-holder. Changing the blank-holder force, meanwhile, adjusting the height of the drawbead according to the needs of the stamping real time, so as to control the quality of sheet forming. To get the optimal combination of variable blank-holder force and adjustable drawbead, this rearch for the technology to control the springback, which has carried on the theoretical analysis and numerical simulation, then providing test for it.

Mechanical alloying is one of the ways how to prepare nanostructured and amorphous metallic materials. In this paper we used this method to prepare Mg-Zn alloy containing 50 wt.% of zinc. Powders produced by milling in a planetary ball mill were consequently compacted by the SPS method, a very fast method which prevents grain coarsening. The prepared samples were subjected to a closer examination - microstructure, phase composition, hardness and short-term thermal stability were studied. We found out that the prepared powder consisted of Mg and Mg7Zn3 phases, which were very fine and homogeneously distributed. After the SPS compacting, the metastable Mg7Zn3 phase decomposed and new phases (Mg, MgZn, MgZn2, Mg2Zn11) formed. The compacted sample possessed relatively inhomogeneous microstructure and hardness about 260 HV5. Investigation of the short-term thermal stability was accomplished by annealing at temperatures up to 300 °C. We observed changes in hardness - it regularly decreased up to 200 °C and then it slightly increased.

This study investigated the effects of squeeze parameters on the properties of squeeze castings and the optimum parameters for producing squeeze castings from Al-Si alloy. It also compared the properties of the squeeze castings with those of chill castings. Squeeze castings were made from AlSi7Mg0.3 alloy using pressures of 15-22.5-30MPa with the alloy poured at 680, 700, 720 and 740°C into a die preheated to 150, 200 and 250°C. Squeeze time was 10s. At the pressure effect during crystallization there is possible to observe the refinement of eutectic silicium with the increasing pressured. Eutectic Si is excreted in clusters in comparison with non-influenced structure. There comes to increasing of failure strength and mainly of elongation. The hardness of investigated samples was not changed markedly. At the pressure of 15 MPa there comes to inadequate pressure influence, what causes the creation of shrinkage in the longitudinal part of the sample. This decreases the mechanical properties.

Contribution presents new principles of inspection technology for examination of integrity of the gas pipelines material and its welded joints. Information is linked with real output from measuring on gas pipelines and results are compared to conventional NDT methods. Visual control is done as a first non-destructive test in 100% extent for all welds. It must be executed well in advance before all the other tests in order to remove superficial defects and irregularities, which could prevent correct application and evaluation of other tests. It is used to detect superficial defects and geometrical irregularities, especially cracks on the surface of weld or in the heat affected area, elevation of weld, undercuts in transitions to base material, defects in the root of weld, if it is accessible from pipe's inner side, including inadmissible offset of weld surfaces from pipe's outer side and their continuity of transition to the weld. The following are the tests to detect internal defects radiographically, respectively by an ultrasound and tests to detect superficial cracks for branches, necks and fillet welds.

High quality products require modern and precise production machines, technologies and quality equipment of industrial metrology. Research paper discusses the possibility of vibration detection at production machines because of process conditions changes. Furthermore, paper also provides a methodology for assessment of vibration amplitude using non-contact laser interferometer, which uses Michelson principle for evaluation. Paper also provides information about a method of vibration amplitude evaluation by contact method using a piezoelectric vibration sensor connected to Balantron 2001 device. The effect of technological conditions on the quality of functional areas expressed by the arithmetic average roughness is experimentally and statistically determined. Experimental study also evaluates the influence of technological conditions during surface grinding on the amplitude of vibration of grinding spindle and provides a correlation between the vibration amplitude of grinding machine and product quality. Moreover, the change of vibration amplitude during three years of production is observed and production capabilities and accuracy of the machine during five years of manufacturing were predicted.

To ensure optimal conditions of instruction in technical subjects it is fundamental to have laboratory trainings where students learn methods of the material measuring and they get pieces of knowledge about a test equipment. Financial cost of samples leads to minimizing laboratory trainings. It can be solved by fused deposition modelling (FDM). The aim of the research was to test a possibility to use test samples made by means of FDM method for an implementation within the practical training. Within the research two standard materials determined for FDM (that means ABS plastic and PLA) were used. Test samples were made / printed by a printer EASY3DMAKER with using a software G3DMAKER. Test of an abrasive wear, a hardness Shore D measurement, a tensile strength and an impact strength were performed for verifying a functionality of the test samples printed by FDM method for laboratory experiments.

The article deals with testing of exchangeable cutting inserts from sintered carbide and determining of suitable chemical composition for their production. The experimental part was based on evaluation of cutting edge insert resistance against heat waves and thermal shocks during the milling process of commonly used stainless steel 1.4301 (X5CrNi18-10). It was determined amount, types and measured lengths each cracks occurred because of heat waves during the milling process for evaluation of proper chemical composition, grain size and content of cobalt for their production.

The article deals with non-destructive measuring and evaluation of residual stresses and chemical properties of stainless steel sample and its possibility to affect functional properties of the material. X-ray diffractometry can accurately determine values of both residual stress and austenite percentage. Due that this method of measuring is non-destructive, it is possible to ensure measure repeatability and measured component is able to keep its original function. Monitoring of residual stresses in components can be useful in predicting damage incidences due to workload over lifetime of components and together with austenite volume it can also be used as evaluation parameter of suitability of applied manufacturing technological operations.

A research analyses an influence of an adhesive surface treatment on an adhesive bond strength. Constructional adhesives used for bonding in an automotive industry were used for the research. A significant factor for evaluating the adhesive bond failure is the research of bonded areas by means of an optical analysis. An even layer of the adhesive in the bond is connected with it. The adhesive bonds diagnostics is difficult. It is necessary to control a quality of the production at the production process. A significant factor lowering the resultant strength of the adhesive bond is its creation. One of possibilities of the adhesive bond diagnostics is to use a method of an optical analysis. An uneven layer of the adhesive belongs among main causes of a failure / considerable decrease of the strength of the adhesive bond.

The article is focused on the analysis changes dependence on the temperature on the aluminium alloy with 10.1% Mg, 1.32% Si and 0.43% Mn by internal friction. Internal friction is a property of the material is measured on the ultrasonic resonant aparature at a frequency about f = 20470 Hz. The measured temperature range was from 50 °C up to 420 °C. Precisely measurement of the internal friction can be monitored ongoing structural changes and various mechanisms that prevent these changes.

The shaping tools or shaping moulds are applied in such production processes like forging, pressing, casting or injection moulding. These technological processes are described by Groover in [1] and Kalpakjian in [2], as well as in the other professional works, e.g. in [3, 4, 5]. A quality of the shaping tools influences also quality of the produced components. This fact is an important aspect in the framework of the whole production chain.The shaping tools and moulds are expensive. An important role is playing the selected production technology of the given shaping tool. If there are applied machining technologies specified for production of the shaping tool, it is necessary to take into consideration also the suitable machining strategies for such technological operation. The term "machining strategy" represents a pre-definition of such tool trajectory in the CAM-system, which is optimised for machining of the various shaped surfaces in order to produce the final product with the highest possible efficiency.[5]

In this paper the technological process of bonded magnets manufacturing was described. The greatest dangers arising during the process steps that have a significant impact on magnetic, chemical and thermodynamic stability Nd-Fe-B bonded type of magnetic materials were also indicated. The effect of the biencapsulation of Nd12Fe77Co5B6 powder particles with Ni-P/epoxy resin, phosphate/epoxy resin and Cu/epoxy resin layers on the finale magnets has been evaluated. The production processes in technological terms in original and after improving modification were presented - the technological process taking into account the stage of powder surface etching and the powder particles biencapsulation. It was proved that the preliminary biencapsulation of particles surface before consolidation in some cases significantly improve the mechanical properties of the bonded with epoxy-resin magnets.

The paper presents a short crack theory together with the finite element method (FEM), which is used to model crack initiation during the operational phase of a pipeline. To simulate the crack, the virtual crack extension (VCE) method, implemented in the FE code, is used. This paper describes the modelling and simulation of a welded pipeline with initiated crack in the beginning. A FEM modelling procedure for analysing the stress intensity factors (SIF's) and J-integral for two practical problems is presented. For the first problem the commercial software ANSYS was used to calculate the crack parameters in a straight pipe with a radial crack. The second problem deals with an axial crack tip in the main pipe of a welded tubular Y-joint. For this problem numerical results for calculated crack parameters and contour integrals are presented. The parameters were calculated by commercial software ABAQUS. For J-integral evaluation, the region on the surface of the blunted notch should be used to define the crack front.

The design of elliptic trajectories of kinematic mechanisms by classical method is a challenge. New method is proposed. Theoretical tests were conducted on a method. It can not be used for scaling and rotation. Some limitations are revealed as well. Geometric modeling showed the method can be applied to arbitrary curves. It should be noted that the theoretical and modeling researches of arbitary curves is not full. Simple robot was designed for processing ellipses. The design of the stand was assembled from aluminum profiles, linear modules and fasteners RK Rose + Krieger. Experiments have shown a difference between the theoretical and actual trajectory less than 5%. The error of stationing was 8,5% before using of the direct analytical method.