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Deflection of cutting tools under the action of cutting forces has a significant influence on the error of machined surface and the stability of cutting process. Considering the complex geometric structure of cutting tools lead to higher calculation accuracy of the tool deflection analysis. Therefore, CAD models of double-sided solid ball end mill and helical drill bit was created in this study. The impact of tool material and clamping of the tool under the influence of cutting forces individually in three axes was obtained via finite element analysis. An error of the numerical model was less than 7.2% and has been validated by analytical calculation. Geometric errors in the case of die and mold manufacturing are provided below or close to 0.02 mm. However, due to the force effect of the cutting process it is not recommended to use HSS tools as the analysis confirmed. Stiffness of sintered carbide tools was more than doubled.

Grinding is an overly used finishing technology, which can obtain very accurate surface integrity. The desirable surface quality after grinding is one of the most relevant parameters. In production, surface preparation such as chromium plating, nickel plating, etc. are more prevalent. These platings are used as protection against corrosion, erosion, abrasion and as a material for the renovation of worn parts. This paper discusses the change of nickel coating machines, which has an influence on surface integrity and microstructure after grinding. The team has built a completely unique and new technical solution for the covered equipment which had never been built in the past. The input parameters were selected based on past experience in the company, related to the area covered in this paper.

Current contribution contains of results of experimental measurements performed within the determination of initial raw feedstock materials moisture content and its influence on final properties of subsequently produced briquettes. A birch wood chips samples with five different moisture contents, specifically 5.0%, 7.6%, 16.7%, 19.0% and 27.7%, were used for experimental investigations. Investigated briquette samples were produced by hydraulic high-pressure briquetting press Briklis, type BrikStar 30-12 with cylindrical pressing chamber of 50 mm. All investigated briquette samples were produced under the same conditions with constant adjustment of all parameters of used briquetting press. A basic physical-mechanical properties of investigated briquette samples were used as a criteria of investigations evaluation. All measured values were subjected to the statistical analysis. Final evaluation of measured values indicated that best results were achieved by briquette samples produced from feedstock material with moisture content equal to 7.6%. Evaluation of current investigation also proved that if moisture content was higher or lower, the quality of produced briquette samples decreased.

Microstructure and mechanical properties of powder metallurgically prepared AlSi24Fe3 alloy are presented in this article. The alloy was prepared in form of rapidly solidified ribbons by melt spinning process. Consequently, the ribbons were crushed into powder in a ball mill and compacted by spark plasma sintering. Grain size of prepared alloy was less than 1 μm, Vickers hardness HV0.1 reached value 214, yield strength and ultimate compressive strength were 611 and 778 MPa, respectively. To obtain material with possible self-healing proprerties, it was necessary to enrich material by fine dispersed Ag2Al particles. The AlSi24Fe3 powder particles were sputtered by 5 nm layer of silver before sintering. The total amount of Ag in bulk sample was approximately 0.1 wt. %. The microstructure of Ag containing alloy was comparable to the basic one. The Ag nanoparticles were present on several particle boundaries. The influence of Ag presence on Vickers hardness of the material was not observed, as the values HV0.1 was 212. After a heat treatment (450 °C/ 1h), silver transformed to equilibrial Ag2Al phase, present in material in form of nanoparticles no more decorating strictly the particles boundaries.

Article deals with design of jig for welding of rail-borne door system on the basis of model and drawing of window frame. Using this jig is ensured right setting and reliable clamping of two bent profiles. By welding of these profiles is made a window frame of automatic door systems for rail-bornes. TIG method is used for welding. Article describes and explains setting and clamping of window frame into jig. Design of control jig for window frames of similar type is embodied in text too. Control jig helps by dimension measurement of window frames.

The paper presents solution to random generation of fibers in composite materials for homogenization using representative volume. Randomly positioned fibers with random diameters of constrained sizes are generated within predefined representative volume, while minimal gap between fibers and volume ratio of fibers in the matrix is maintained. The problem of random generation is solved as an optimization problem using a custom memetic algorithm designed by the authors. A comparative study was performed, comparing performance of memetic algorithm and genetic algorithm.

In modern times there are increasing requirements for quality of products in every part of manufacturing industry. In foundry industry it is not different and from the point of view of quality the most dangerous are hiden casting defects, such as shrinkage cavities. That is why a lot of foundries are researching, how to increase the efficiency of producing castings. This experimental work is dealing with search of the influence of carbon and silicon content in ductile iron on shrinkage creation. In the experimental part there is introduced the production process of test castings and results of ultrasound non destructive method. The object of this paper was to determine the influence of two main alloying elements of ductile cast iron on shrinkage creation with preserving specific strength of mould, which also has an impact on shrinkage creation.

The use of a new method of attaching fixed blades to a stator disc led to the need for evaluating the strength of a riveted joint. Conventional mechanical testing revealed large variations in the strength of this joint. After sectioning the joint, it was found that the shank did not fill completely the hole in the shroud of the disc. Further investigation involved numerical simulations using the DEFORM software, because securing additional samples for physical examination was complicated. The first simulation task focused on determining the tearing-out force, taking into account work hardening of the shank material due to plastic deformation. The second simulation task aimed to identify optimum initial dimensions of the shank. The goal was to ensure that the rotary upsetting process causes the shank to completely fill the hole in the shroud. As a result, the joint strength would be improved and, above all, the variation in strength eliminated.

Evaluation of the diffusion process is the plasma nitriding technology in connection with an increase of fatigue life of steel. For experiments steels 41CrAlMo7-10 and 34CrNiMo6 were selected. The equivalent of mentioned steel is material no. 1.8509 and no. 1.6582. Plasma nitriding technology belongs to the group of chemical-heat treated process. This process includes the saturation of nitrogen to the core of material. Plasma nitriding technology is effective method usage in practise especially in order to increase the surface hardness, corrosion resistance and fatigue strength. The experimental material samples were heat treated and subsequently plasma nitride. Fatigue bending rotation tests were the major part of the experiments. According to the principle of the experiment the rotation velocity was determined as constant and the load of samples was going down. The experimental measurement were stopped in case of fracture or after 107 cycles without damage. Fatigue life of the steel depends on the thickness of a diffusion nitrided layer. This thickness was evaluated by using the microhardness measuring from the surface to the core of the material. The results of experiments shows that these steels are suitable for increasing fatigue life after the plasma nitriding process.

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

The article deals with a comparison of machining of two chemically very similar materials of aluminium alloy, however, with various internal structures by means of non-conventional machining technology of electro-erosive wire cutting (WEDM). The first material used was a right parallelepiped of ALPORAS aluminium foam with porous structure produced by a method of powder metallurgy. As the second material designed to the comparison EN AW 5005 alloy was chosen owing to high aluminium content and therefore a very near chemical composition of the compared material. The samples with circular section of identical height and nominal diameter were produced. On the tested materials sizes of the cutting width were tested, surface structures after machining were observed, dimensional accuracy of cut samples were evaluated and time relationship between cutting of compact and porous structures of aluminium alloy were defined by means of a microscope.

The design of the gating system is a major factor in the internal homogeneity for casting. A properly designed system should ensure a proper and continuous filling of cavities in a mold. A continuous filling in a mold cavity gives the initial condition for internal soundness and homogeneity when casting, which in turn is reflected in the quality and mechanical properties. The geometry and shape of the gate models and directs the melt stream entering the mold cavity, this greatly affect the properties of the castings. Homogeneity of castings closely correlates with the mechanical properties of castings. The present paper is devoted to analyzing the effect of the dimensions of the inlet slit on the homogeneity of the casting. As the width of the gully is constant according to the design method of the ingate systems, the variable parameter was the height of the gate. The aim of the experiments was to find the most advantageous height of the gate that is necessary to achieve the lowest porosity values. The boundary values of the height of the gate were determined based on the numerical design of the ingate system for the particular casting and the NovaFlow & Solid simulation program. The porosity analysis f was performed by the OLYMPUS GX51 microscope and the evaluation of the samples was carried out using the ImageJ computer program.

We can reach significant results in the field of waste reduction in production processes with application of the tool and rule systems of lean philosophy. One of the frequently applied lean methods is SMED (Single Minute Exchange of Die), which is able to reduce the changeover times and the resulting wastes. Length of the changeover time has a relevant effect on several parameters of the production process (inter-operational inventories, batch sizes, production lead time, manufacturing flexibility, etc.), consequently its reduction is an important competitive factor for a companies. The paper introduces in detail the role of the set-up time in production logistics and its reduction possibilities in real-life situations as well. We examined and summarized the application possibilities of simulation modelling for the efficiency increase of the SMED method as well.

Results of an experimental research of friction coefficient in "alumina ceramics - quartz glass" friction pair are presented. The research with pin on disc test configuration using SRV-III test machine was carried out at loads from 10 to 1000 N, constant sliding velocities 5 mm/s; ambient temperature 23°C and relative humidity 30%. The obtained results reveal that in general, friction coefficient for "alumina ceramics - quartz glass" pair decreases with the increase in normal load. It is shown that the obtained friction coefficients values at the normal force from 100 to 1000 N for the given experimental conditions can be used to pre-estimate the interference fits in "alumina ceramics - quartz glass" friction pairs.

This article is belonging to the publication series, which we published in the previous issues of this journal and there are described the most important and innovative research and development design solutions and computational procedures as part of European structural funds project. The main object of article is the strength test of new design of freight bogie frame through FEM analysis. For the calculation of the analyzed parts of the bogie through finite element the program ANSYS was used. Results of calculations prove, that new designed construction of the bogie frame satisfies strength conditions.

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

Firefighter ladders are manufactured of aluminium alloy AA 6063. These ladders are a widely used technical tool for firefighting, for intervening firefighters and for rescued persons. The quality of the ladders is checked by so-called "user test" which is a non-destructive deflection test defined by CSN EN 1147. Unfortunately, this test is not sufficiently conclusive in terms of safety. Therefore, the project called "Safety improvement of extension ladders for firefighters" (VI20162020021) is focused on the complex assessment of the existing firefighter ladders through mathematical modelling, material analysis and real testing. In the present work structure and mechanical properties of samples (aluminium alloy AA 6063) taken from different areas of a firefighter ladder are presented. The obtained result confirm excellent mechanical properties of selected samples, such as tensile yield strength and ultimate tensile strength, at laboratory temperature but a huge decrease in these properties after exposure to temperatures above 200 °C for even short times. This results in the necessity to control temperatures in the proximity of the ladder, especially in the case when the ladder is located near a flame.

Reverse engineering is a technology that enables acceleration of data collecting for CAD, CAM, CAE systems, which also means shortening time of development, construction and components production. It is a transfer process of a physical component to a digital format. Generally, the technology of reverse engineering means a conversion of analogue data to digital data that are further processed. Every single industry branch rising their requirements on accuracy, dimension, quality, etc. Therefore, digitisation is applied in many production fields such as an automotive industry, aircraft or shipping, medicine, industrial design, design, etc.
An article deals with an analysis of prototype models of gears in various stages of production. The realized inspection of a shape of prototype gears lied in uploading of a digitised referential CAD model (the gear after heat treatment and machining), subsequent setting up of digitised prototype gears (the gear after the machining, gear after heat treatment) in respect of this referential CAD model, a control of their dimensions and forming a colour map of deviations in chosen points.

This paper deals with problems connected with defects in polymer composite materials and the causes of their occurrences. The microstructure of polymeric materials with carbon and hybrid (carbon / aramid) reinforcement with an epoxy matrix is examined. The evaluation of the microstructures of the two types of composites was performed with the aid of a scanning electron microscope, as well as a 3D light microscope. Defects (dry spots, bubbles, pores,…) in the structure of the material significantly affect its properties, and the question of their elimination is also considered. In order to achieve the most favourable physical and mechanical properties, the production method for the composite materials is important. While preparing test samples, it was used manual lamination technology, where 45% volume fraction of fibre reinforcement could be achieved in the technological regularities.

This article deals with unconventional materials usage in design of vehicle bodies. Main focus is on sandwich materials (with honeycomb structure) for walls of the main body. These panels are designed from polypropylene. Joining of theses sandwich panels is also solved here by special aluminium profile. Virtual simulations and stress evaluation are used methods for design evaluating. Research is focused also on material properties testing. Tested are sandwich materials and also connecting aluminium profiles. All material properties and testing principles are here clearly described. Lower weight of vehicle body leads to possibility of floor optimization. Welded frame of floor can be lighter and strength of floor is also evaluated here. All these steps lead to lighter design with economic benefits for producer.

Quality design is necessary prerequisite for correct and safe operation of all mechanical devices. This design has to consider all simulations and calculations. All boundary conditions have to be involved in this design. Ignorance of some of them can lead to overloading of structure or to the destruction of whole device, as shown in the example in this paper. Following design solutions can improve these mistakes, but this is technically difficult and costs are much higher. This article deals with calculations of air piping and with supporting structures for this system. This example from praxis shows importance both simple calculations and advanced structural simulations. Benefits of advanced FEM simulations are shown clearly using described structure. These benefits can be applied on all mechanical systems.

Main aim of this article is description of weld line influence on mechanical properties of plastic parts. Special design of mold was created for this research. This mold is able to create specimens with and without weld lines. These specimens undergone tensile test according standard ASTM D638 with different results. Strength and strain results were compared for both types of specimens. Nylon PA6 without any internal reinforcement was used as reference material during testing. Both specimens were investigated also by microscope in order to see composition of weld line and plastic material. Microstructure showed geometry of weld line and also fracture surfaces indicated presence of plastic deformation

The paper deals with examination of dynamics of linear hydraulic cylinder with mass load. The hydraulic cylinder is placed in vertical position. There is experimentally simulated a system state. In this case a higher piston velocity is achieved due to the mass load compared to the piston velocity that corresponds to a supplied flow. A piston oscillation of the hydraulic cylinder is caused by rapid stop of movement in a desired position. There are experimentally evaluated eigenfrequencies of the linear hydraulic cylinder depending on the piston position and the mass load. Mineral oil was used as the working liquid. Time dependencies of pressures are measured on sides of the piston and the piston rod. Furthermore there are measured time dependencies of the piston position and the oil temperature. A mathematical model is created for this hydraulic system. This model is realized by Matlab SimHydraulics software. There are simulated time dependencies of the piston position and the pressure on the side of the piston rod. The mathematically simulated time dependencies of the pressure and the piston position are compared with the experiment.

DEFORM™ is a robust modelling software tool which uses the finite element method (FEM) for modelling technologies in 2D and, naturally, in 3D. One of the processes, the modelling of which DEFORM™ supports, is slab milling.
For this purpose it uses an advanced FE model with various parameters, such as the fracture criterion. If their values are not chosen correctly, the desired results cannot be obtained.
A 3D simulation model was developed to explore the capabilities for entering data, calculating and evaluating temperature distribution within a workpiece during experimental milling carried out under real-world cutting conditions. The FEM model concerns the temperature on the rake face of an exchangeable cutting insert. The primary aspect which was monitored was the temperature field during chip formation.
Finally, the results of the simulation were compared with data from a machining experiment. The material used for the simulation and for the machining experiment was the ČSN 12050.1 / AISI 1045 steel.

Manufacture of new parts of machineries, devices, etc., especially in engineering and metallurgy requires machining of the feedstock in a mechanical way. During machining occurs immediate contact between the tested specimen and the tool and in their mutual relative movement of friction and wear. One of the possible variants how to eliminate this fact is the application of process fluids during machining.
Currently, we are trying to simulate long-term testing by laboratory testing called tribology. The experiment presents friction between two materials that are under real sliding contact. This article examines the tribological characteristics between two materials (tool - ball and workpiece material - disc). The paper contains findings when examining process fluids by tribological test Ball - on - disc, this test is currently used in practice, very widespread, this test can imitate various operations of cutting machining. This paper deals with the evaluation of tribological properties (the coefficient of friction, wear of disc and wear of ball) between the ball from ceramic material Si3N4 and the test material (stainless steel X5CrNi18-10, EN 10088-3 and steel commonly used in engineering 16MnCr5, EN 10084-94) by using two kinds of process fluids.

New concept for pressure testing samples has been designed based on previous experiments which investigated the maximum load capacity of a Schoen Gyroid. This pre-experiment pointed to the possible lack of measurements and newly designed pressure samples intended to improve measurement accuracy. This paper focuses on the manufacturability of the designed samples made by selective laser melting, which is able to produce complex metal parts using support structures. However, removing the support structures from a porous core is impractical. In this context, the ability to substitute supporting structures by a Schoen lattice structure is also marginally dealt with. The paper concludes with the benefits of the optimized pressure samples over the old concept. An increased maximum load capacity was achieved by the addition of contact plates, which constrain the strut ends.

Gases evolving from moulds, cores, coatings deposited on sand and metal moulds constitute one of the basic reasons of several casting surface defects: blow-holes, pinholes, pitted skin, etc. In research performed up to now the moulding sands gas evolution is determined in two ways: normalised, in which the gas amount emitted from the sample placed in a heated flask is determined or in the other way, in which the gas amount emitted from the core - covered with liquid metal - is determined. In these both methods the result constitutes the total amount of gases emitted from 1g of a moulding sand and the emission procedure as a time function. The new method of investigating the kinetics of gases evolution from moulding sands (and coatings), applied for making moulds, is presented in this paper. The kinetics is tested not only as the heating time function but also as the temperature function. The method was developed in the Department of Mould Technology of the Faculty of Foundry Engineering, AGH. Amounts of gases emitted from the moulding sand at the given temperature in the time unit are obtained in investigations. The results of testing the group of moulding sands (furan, alkide, moulding sands with water glass) and the group of protective coatings applied for sand and metal moulds, are presented in this paper.

The aim of this study was to find possibilities of using the Fourier transform in the analysis of vibration load tests of heterogeneous mechanical systems, especially those of a biological nature. The study applied the idea that the dispersion of a stationary stochastic signal depends on its power spectral density. We have verified that a sophisticated reduction in the spectral power of the ergodic signal may be used to filter it effectively. The proposed procedure is suitable for the detection and separation of harmonic artefacts. We have created an algorithm in the MATLAB environment and tested its functionality when analysing the vibration transfer within the human axial system.

The paper describes the research focused on the influence of the antimony as the modificator in the one of the most common aluminium foundry alloys - alloy AlSi7Mg0.3. The aim of described experiment was to examine the antimony addition influence on the AlSi7Mg0.3 alloy microstructure changes. The description of the changes was performed based on the analysis realized using confocal laser microscope and electron microscope complemented by energy dispersive spectrometry in microstructure induced by the addition of antimony. The changes in the alloy microstructure, which were evoked by the addition of antimony, caused the mechanical properties changes (especially ductility). This is the main purpose of the Al-Si alloy modification process. Mechanical properties of the alloy were analysed using static tensile test and the main parameter of the observed changes was the increase in ductility.

The utilisation of pure molybdenum in high-temperature applications in a vacuum requires very precise machining. Considering the fact that conventional machining methods do not achieve the required geometrical and dimensional accuracy in several cases, it is necessary to use the unconventional technology of wire electrical discharge machining (WEDM). This study aims at analysing the surface and subsurface layer of pure molybdenum after WEDM in terms of the occurrence of defects. Profile and areal parameters were evaluated by means of a contact 3D profilometer. The occurrence of individual defects both on the surface and underneath it was studied by means of the methods of electron microscopy and focused ion beam (FIB). Furthermore, the local chemical composition of the surface of the workpiece (EDX) was determined.