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Grinding is a significant and very commonly used technology, allowing for important gains in surface integrity. The surface integrity quality after grinding is one of the most important parameters, which is prescribed on the production drawing. Chrome plating as protection against corrosion, erosion, abrasion and as a material for the overhaul of worn-out parts is used. This paper discusses the change of cutting conditions when samples were ground. The surface of all samples was preserved with galvanically applied chrome. The values show which grade of surface roughness is attained when selecting different cutting conditions. The results of surface integrity after grinding were evaluated depending on the comparison of the parameters of roughness. The input parameters of cutting conditions were chosen based on the experience, which was implemented.

This article deals with state-of-art in the field of handling machines intended for disabled people, which serve for disabled entry of such people and for people with delimited locomotion. It contains calculation of forces, which act in the mechanical system of an electric device during its operation in real conditions, changes of reactions depending on the load and the climbing angle as this solved handling machine will designed for negotiation of staircases. The objective is the functional calculation of a driving mechanism of a stair chair marked SA Alfa, i. e. the calculation of loading forces and their action on the driving mechanism. It will serve in the next step as an input for the calculation of a required power under conditions of occurance of maximal resistance forces, which will be determining factor for dimensioning of driving components of this device.

Today, extensive information on a particular material can be obtained from its chemical composition using various computer programs. Such information includes phase transformation temperatures, such as Ac1 and Ac3 or the Ms and Mf, as well as the entire austenite decomposition sequence, as shown in TTT and CCT diagrams. When steel is heated, austenite grains begin to form, grow and eventually coarsen. On cooling, these grains decompose into pearlite, ferrite, cementite and hardening phases. Transformations of this kind are well understood nowadays, namely the ways the individual phases form and the rates and temperatures involved. Yet, in-situ visual recordings of such transformations are relatively rare. Using the Linkam TS1400XY heating stage, which is capable to heat samples up to 1400°C and is integrated in an optical microscope featuring objective lenses with modified working distances, these phase transformations can be observed directly. This paper explores the potential of the heating stage for studying various materials and their specific heat treatments. It also discusses the method of sample preparation for use in the heating stage placed in an optical microscope.

Development of methods for machined surface identification has reached a stage when real surface shape can be visualised more precisely. Mechanical tools for measuring roughness have shown misrepresented profile considering the fact that the tip of diamond sensor is not "ideally sharp", it only follows the outline of actual profile. Profile details can be followed by optical scanning. During observation of profile records and theoretically defined rounded tool tip copying considerable disproportions can be found. This fact leads to incorrectly determination of feed with defined value of Rz and selected tool tip radius in practice. The aim of the paper is to identify the reasons of such differences and suggest a process of their elimination.

Grinding is currently still an important method for surface finishing. At FPTM JEPU is realized the research, which deals with this issue. There are carried out experiments with grinding various materials under different conditions and then are evaluated the selected components of the surface integrity, which are generally roughness Ra, Rz and Rz, material ratio curve (Abbott Firestone curve) and also obtained roundness. This article deals with grinding nickel alloy Inconel 718, when selected cutting grinding conditions were used and subsequently the surface roughnesses Ra, Rz and Rt, the surface profile and the material ratio curve were measured and evaluated.

The article deals with influence of chemical etching and polishing on some roughness parameters of titanium parts surface, designed for implantation into human organism. Titanium alloy Ti-6Al-4V was used for the experiment. Analysed samples were created by conventional mechanical machining methods as milling, grinding and polishing. Influence on surface and quantity of removed material by acid solution was analysed. Three methods of sample surface finishing were used, each resulting in variety of surface quality, and then two methods of chemical polishing, differed by reaction time of acid with samples surface. The samples surface was analysed optically, using stereo-microscope and evaluated roughness parameters as arithmetic average roughness Ra, ten-point mean roughness Rz, profile skewness Rsk and kurtosis Rku were measured. The modification of these parameters after the reaction was measured and analysed.

The present study was directed to investigate the mechanical and tribological properties of 42CrMo4 (CSN 41 5142.3) steel, which was thermochemical treated by the technologies of tenifer, manganese phosphate and plasma nitriding combining with blackening. Plasma nitriding was carried out for the samples under different condition of gas mixture under temperature of 480ºC (plasma sputtering) and 500ºC (plasma nitriding process) for 10h. Besides determining the microhardness (HV 0.05), surface hardness, and microstructure, this paper also concentrates on the field of wear resistance evaluation and friction coefficient of these surface treatments. Based on "ball on flat" test, calotest, and profile observation, it was found that tenifer technology is suitable to increase the wear resistance, and manganese phosphate improves clearly not only wear resistance but also friction coefficient, which can be usable for weapon production.

This article builds on existing results of testing hardened steel bearing ring machining. Grinding technology is preferably used for this area as a standard. Turning with cubic boron nitride has been used as an alternative machining technology. Results indicate that in mass production the values accuracy of degree IT 4 can be achieved. Arithmetic mean deviation of the profile is then in the range of Ra = 0.2 - 0.4 μm. During testing several kinds of cubic boron nitride material were used. The material that showed best results was chosen for further experiments. Subsequently it was tested under different cutting conditions on two types of machine tools. It was tested cutting in smaller range of depth of cut and wider feed values. The resultig feedrate and cutting depth which correspond to best result of arithmetic mean deviation of the profile Ra were selected from those tests. Subsequently, the testing was carried out at various cutting speeds and particularly at two different sizes of tool overhangs.

The results of an experimental study on influence of cerium addition on structural characteristics of 42CrMo4 steel are presented. Alloying with cerium was carried out using profile filled with powdered mixture of mischmetal. The samples were taken from two ingots cast in the VHM's steelworks with standard time of casting of about 14 minutes. Three steel bars from one of the produced ingots were prepared by forging. Chemical composition, macro- and microstructure, X-ray EDX chemical microanalysis, hardness of the all steel samples were obtained. Cerium addition resulted in the formation of micrometer size inclusions which can be utilized for controlling the grain size structure of steel castings. The majority of the particles have settled at the bottom part of the casting, indicating that the convection flow during solidification was very weak. The cerium addition slightly diminished hardness of the steel. A segregation phenomenon causing inhomogeneous distribution of cerium over entire volume of as-cast samples after relatively rapid crystallization process of the steel was revealed.

Ball-section raceway groove and narrow groove ring (BGNGR) is a complex part of bearing rings. The mandrel for the forming of the narrow groove will push and press the metal and lead to instability of the rolling process. Therefore, the effect of the narrow groove on the metal flow is investigated. Two methods for BGNGR rolling are presented, and by deducing the dimensional relationship between rectangular blank and deformed ring, the finite element models for both methods are established and simulated in Forge3D software. Method I is proved to be a failure through the finite element analyses of the effect of the narrow groove on the metal flow. Based on the analysis result in Method I, the Method II with appropriate mandrel profile for the going up metal is proposed. The simulated result shows that the BGNGR whose geometry size meets the requirement can be rolled by Method II.

The paper deals with heat affection of selected armoured ultra-high strength steels after their cutting by plasma and laser and their welding with using MAG welding method where critical degradation of mechanical properties could occur in heat affected zone after application of these technologies. Armox steels are armoured ultra-high strength martensitic steels with the usage in special technology. The steels are produced in the form of forged semiproducts as sheets and plates. These sheets are cut and most commonly welded in a way to made the final product. Experimental samples made of Armox 500 steel with using of aforesaid thermal based technologies are studied in the paper to evaluate selected heat affected zone parameters.

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.

The paper deals with the design of a special machining tool for efficient production of detail on the T-groove of the clamping part. The introductory part of the paper is focused on introducing the Czech company. The practical part of the paper deals with the analysis of the existing state of machining of the clamping body and of the production of the T-groove detail and proposes an innovative solution in the form of more efficient machining process (partial production modification), which consists in the development and production of a special tool with replaceable inserts. The main reason for this partial modification is a significant reduction in unit machine time in the production of the T-groove detail on clamp body parts. Part of the contribution is in the process of streamlining the innovation made in the form of changes to the manufacturing process and the design of the cutting conditions required to produce the T-groove detail on the clamp body parts. The contribution is completed by a technical and economic evaluation, which is related to the analysis and comparison of both proposed production variants in terms of machine times, tool consumption / replaceable inserts and total production costs for the T-groove detail production on the clamp body parts.

The paper deals with the strength conditions assessment of new design of modern railway bogie through FEM analysis. The bogie, which was developed as part of European structural funds project, is characterized mainly by better dynamic properties while driving on the track, higher safety against derailment and lower negative effect on the track (reduction of wear). For analysis of bogie frame, there has been created a substitute simulation model. Results from calculations and prototype tests prove, that investigated design of new construction satisfies strength conditions.

In metals processing, 3D printing is a relatively new technology. It brings many advantages into production thanks to its additive principle on which it is based. One of the intended applications of 3D printing is especially regenerative medicine and aerospace industry that require products of very complex shapes. In these domains, titanium along with its alloys belongs among the most frequently used materials. When printing a Ti6Al4V alloy, very high cooling rates during the successive laser melting of an initial powder material result in high internal stresses. These stresses are followed with several problems, such as low material plasticity, possible cracking of built products, deformations of thin parts and similarly. Therefore, after the 3D printing process itself, a thermal treatment is applied to relief the stresses. The object of this study is to show the influence of atmosphere in thermal treatment process on the quality of final parts. The results show that oxygen absence is essential in terms of material plasticity.

The give paper is closely connected with the analysis of the normal force relating to the winding mechanism referring to production or manufacturing of raw tyres. The attention is mainly paid to the calculation of normal force during the manufacturing process when the individual constituents of raw tyre are pressed-in. The dynamic analysis as well as the calculation of the given normal force was done for raw truck tyre. The simulation of the movement and dynamic analysis for the given kinematic conditions as well as appropriate input values were solved in Solid Works - modeling computer program. Courses of normal forces for the first one set and the second one set of winding arms in dependence on lever position are in graphitic form. Based on the dynamical analysis, it can be concluded that, the second one set of winding arms does not have any influence on the quality of the produced car tyre.

This paper deals with non destructive evaluation of components after plasma nitridation via Barkhausen noise techniques. The effect of the different surface state before plasma nitriding is studied via non destructive Barkhausen noise technique as well as the conventional destructive techniques. Turning operation was performed by the use of the inserts of variable flank wear. The results of experiments show that Barkhausen noise emission is a function of tool flank as well as the different regime of heat treatment. The different state of the surface before plasma nitriding results into the different thickness of compound layer. Furthermore, also the underlying diffusion layer state differs.

Aiming at a kind of grinding head of high-speed precision roll grinder, its structure characteristics and heat source characteristics are analysed, and the characteristics of heat source is calculated. On these bases, the weakness of grinding thermal characteristics is found through the numerical analysis of thermal performance of roll grinding head, facing the thermal error of sensitive area, optimization method which unites multi objective and single objective are adopted to optimize the thrust oil film bearing of the roll grinding head, after that numerical analysis of thermal performance of roll grinding head is analysed. Analysis results show as follows: temperature of the optimized oil film thrust bearing is improved obviously. The oil film performance between the bearing and the main shaft is stability, and it has had effective prevent the phenomenon of metal dry friction happening. As a result, the grinding accuracy of the grinding roll is effectively improved.

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 paper deals with surface integrity after hard milling of bearing steel 100Cr6. Surface integrity is expressed in terms of shape deviation as well as Barkhausen noise emission. Furthermore, components of cutting forces are also measured as a function of tool wear. Non homogeneity of cutting force distribution within the contact between the milling cutter and workpiece is discussed. The results of measurements indicate that shape as well as structure remarkable non homogeneity should be expected after hard milling due to missing full contact between milling cutter and workpiece. This non homogeneity can be monitored via Barkhausen noise technique. On the other hand, the competitive grinding cycles produced more homogenous surface and surface state is a function of infeed speed.

Titanium aluminides with various amounts of aluminium were prepared by Self-propagating High-temperature Synthesis (SHS). Ti-20 wt. % Al, Ti-38 wt. % Al and Ti-63 wt. % Al were chosen according to Ti-Al phase diagram, because these chemical compositions represent Ti3Al, TiAl and TiAl3 phase, respectively. The effect of the amount of aluminium on the combustion temperatures, microstructure and phase composition was studied. Heating of compressed samples was observed by optical pyrometer to determine exothermic reaction which is associated with SHS reaction. It was found that reaction temperatures increased with increasing addition of aluminium as well as reaction time and the start of ignition. The expected dominant phases were determined in all systems after SHS reaction. However, other phases accompanied their formation. The largest variety of phases formed in Ti-38 wt. % Al system.

The article deals with the research of the measuring probe signal of roundness machine Roundscan of Jenoptik IM producer. The probe of this machine scans geometric form as well as surface structure. The probe signal dependence on the probe arm elevation is not perfect linear and this influences the precision of evaluated form characteristics, roughness parameters as well as drall parameters. A quantification of calibration way influence on the signal characteristic was main research task. A calibration process simulator was designed and built in MATLAB for this. This article describes a way of obtaining of real probe signal. Metrological filters according current standards ISO 16610-21 and ISO 16610-22 were built in MATLAB for obtained signal filtering. The calibrating simulator simulated various master standard values, various probe arm starting positions before the calibration, various probe arm starting positions before subsequent common measurement, and tolerance limit utilisation during a master standard value transmission to the probe signal. An efficiency of signal linearization procedure was explored, as well. Obtained results are presented as signal zones, which delimit assigned signal deviations from perfect signal characteristic.

One of the basic principles of railway vehicles is their carrying and guiding. In the contact pair of a wheel and a rail, one body is rolled on the surface of the other part and all main forces are transmitted in this contact. Contact between wheel and rail is also important from an economic aspect as it is related to the wear of the track rails and the wheel thread itself, including the wheel flange, and has caused the necessary maintenance of the track and the vehicles themselves. Therefore, our article focuses on simulating the influence of a flat wheel on changes in wheel forces. The model was created in the CATIA program and was consequently imported into the SIMPACK program, which was followed by analysis of the passage of the vehicle along the track. In the simulation, we considered an ideal track and a wheel flat on the right front wheel. We also plan to work with these results by adding and comparing them with results obtained by applying irregularity to our ideal track.

The paper is part of the publication series, which describe the most significant and innovative research and development design solutions and computational procedures as part of European structural funds project. The object of this article is strength conditions assessment of a new structure of railway tank wagon. For validation of the new construction assemblies, there has been created a substitute simulation model. Results of calculations and prototype tests prove, that new structure of the construction satisfies strength assessments according to valid requirements and standards.

The usage of the high-energy electron beam source enables repeated surface quenching of chosen areas of an engineering part surface. Different techniques of electron beam deflection allow creating of hardened layers of different shapes and thicknesses. Experiments were carried out with 42CrMo4 (1.7225) steel. The deflection modes tested were one-point, 6-point, 11-point, line, field and meander. The influence of process speed and defocusing of the electron beam was also taken into account. The electron beam surface quenching resulted in a very fine martensitic microstructure with a hardness of over 700 HV0.5. The thickness of the hardened layers depends on the deflection mode and is affected directly (except field deflection) by process speed. The maximum hardened depth (NCHD) was 1.49 mm. Electron beam defocusing affects the width of the hardened track and can cause extension of the trace up to 40%. The hardness values continuously decrease from the surface to the material core.

AISI 316Ti is Cr-Ni-Mo austenitic stainless steel stabilized by Ti, recommended for construction of various industrial and medicine devices. In spite of its high Pitting Equivalent Resistance Number (PREN=23.688) it underlies local corrosion namely pitting in aggressive chloride environment. Appearance and extent of AISI 316Ti corrosion damage in a particular chloride solution depends strongly on temperature and surface treatment. One part of tested specimens is surface untreated the second part is treated by nitric acid passivation. Specimens are immersed for 24 hours at the temperatures of 30, 50 and 80 °C in 0.3M FeCl3 solution to induce pitting. Pitting corrosion morphology (shape and size of corrosion pits) is observed viewed from above and in profile as well, by optical metallographic microscope and scanning electrone microscopy SEM. Shape and size of corrosion pits is compared in dependence on temperature and surface finish of specimens.

Results of signals analysis was done using wavelet transform, which have different curves of wavelets and depend on the basic wavelet, which were applied. Thus, it is sometimes not possible to conduct a wavelet transform of a given profile with the use of any basic wavelets and to obtain results that are similar to the measured signal. The aim of this was work was an optimization of a basic wavelet selection used for an analysis of surface roughness. In the work an analysis of Abbot-Firestone curve parameters was performed on subsequent decomposition levels and for various basic wavelets.

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.

During the metal machining amount of dust is generated which can influence significantly surroundings, but mainly workers are exposed to dust pollution. The aim of this paper is to present results of microclimatic research focused on dust pollution in workshop during the milling of aluminium alloy workpieces. The concentration of air dust was measured by the DustTRAK II Model 8530 aerosol monitor. Using the special impactors the PM1, PM2.5, PM4, PM10 size fractions were also measured. Obtained results of measurements and concentrations of different size of dust particles were analysed. Results of measurements under different milling conditions are generalized. The conclusion of the research is that it is necessary to watch the optimization of the milling process as well as secondary effects of the technological operations and inner environment of workshops which can be contaminated by chemical substances as well as dust particles.

Comprehensively considering the analysis results of the microstructure, hardness and tensile properties, different zones of a component for aircraft applications manufactured through hot stretch forming were studied. The differential thermomechanical story of each studied zone of the forging was taken into account. The results reveal that the different zones strain hardened in function of the degree of the strain and strain rate experienced during the forming, with the zones most stressed at the higher strain rate showing the best tensile properties and a loss of ductility. This phenomenon is not coupled with a visible change into the microstructure morphology of the processed material.