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Machining of titanium is quite difficult and expensive. Heat generated during the process of cutting does not dissipate quickly, which affects tool life. In the last decade ultrafine-grained (UFG) titanium has emerged as an option for substitution for more expensive titanium alloys. Extreme grain refinement can be readily performed by severe plastic deformation techniques. Grain refinement of a material achieved in this way was shown to change its mechanical and physical properties. In the present study, the microstructure evolution and the shear band formation in chips of coarse grained and UFG titanium machined to different cutting speeds and feeding rates was investigated. It was demonstrated that an improvement in the machinability can be expected for UFG titanium.

This article presents particular results from a long term research focused on machining of INCONEL alloys. As a representative of this group of material INCONEL 738LC is selected and the article presents results of different experiments conducted. The behavior of material under different conditions was evaluated with focus to define cutting condition that can be recommended as suitable cutting conditions for profile milling of material. Basic problems of profile milling are exposed with focus to the respective material. Several machining experiments are explained and archived results are discussed. Effect of tool geometry and geometrical constraints and relations during profile milling is defined. Tool wear and cutting forces were measured and evaluated. The final conclusion is a recommendation for successful machining of given material.

Grinding is one of the technologies for surface finishing of large scale of material. This paper deals with grinding of titanium alloy Ti6Al4V with silicon carbide grinding wheel. Ti6Al4V is the most widely used titanium alloy. Its utilization can be found in medical, aerospace, chemical and other industries. This experiment deals with evaluating of surface roughness after grinding. The roughness parameters (Ra, Rz) were measured on each specimen ten times. Also cutting forces were measured while grinding each specimen. All these measured values were evaluated and presentated in graphs.

The purpose of using modern technology is to reduce costs, facilitate the work and simplify as far as the most comprehensive set of operations. One of many modern technological processes involved in the refining of materials are technologies of surface hardening using a laser beam. This method can harden precisely defined areas with minimal thermal influence of surrounding areas it is possible to achieve less residual stress and less distortion of components compared the volumetric hardening, it is also possible to use controlled robotic units and all for the absence of cooling, which proceeds spontaneously to the surrounding material itself and atmosphere. These advantages of laser surface hardening are used by companies for which the prospect of minor damage to the material, increase of the material durability, material stiffness ensuring etc. is initiation for the use of modern technology.

Semi-solid processing allows novel microstructures to be produced even in conventional materials. This is thanks to the peculiar conditions of the process and the rapid solidification. Despite that, semi-solid processing is not widely used in practice due to its technological complexity. Mini-thixoforming is an innovative method of processing metals in the region between their solidus and liquidus temperatures. With its small volume of the metal feedstock, it is a very precise and highly dynamic process. Consequently, it can be employed for materials with a very narrow freezing range which, until now, were impossible to thixoform conventionally. The present experiment focused on one of such materials: the low-carbon high-alloy age-hardenable X5CrNiCuNb16-4 steel. Owing to the low carbon level, the relevant temperature interval was 1380 - 1420 °C which, together with the need for strict control, posed a technological challenge. Once the semi-solid processing parameters were optimized, the die cavity was filled as required and the final products showed good surface quality. The resulting single-phase microstructure consisted of ferrite. Hence, given the 17% level of dissolved chromium, there is a potential for excellent corrosion resistance and, possibly, for subsequent age hardening of the material

One of the main problems in machining Al alloys represents built-up edge formation. This paper is focused on the effect of selected modifiers in AlSi7Mg0.3 alloy on built-up edge formation. Four variants of castings modified by strontium, calcium and antimony are used. All these alloys are compared with non-modified alloy. Built-up formation leads to the increasing of surface roughness for both types of built-up edge - unstable or stable. If unstable built-up edge is produced, surface roughness increases enormously. Therefore the research is focused on surface roughness in different cutting conditions. There were moulded castings of non-modified alloy and for each modified variant. Gravity-die castings into a metal mould with a thermal insulation were made.

Evaluation of cutting tool wear is the technique generally used when monitoring cutting tool life. Different tool wear types increase depending on the cutting conditions and machined material on the cutting edge surface. The evaluated parameters depend on the tool wear type and where the tool wear is created. All these parameters are described by ISO 3685 standards. When a standard optical microscope is used, it is very difficult to determine the volumetric parameters and, in many cases, the actual (real) area of the tool wear. A standard optical microscope works on the basis of 2D screening. The new microscope works on the basis of 3D scanning, so the user has full information about the surface. This article is focused on the evaluation of the volumetric parameters on the cutting edge, on the size of the built up edge (BUE), and on the formation of the crater. Different coating types on the cutting inserts were used for the testing, and a IFM G4 microscope was used for monitoring and evaluating the tool wear.

X37CrMoV51 tool steel for plastic working and heat cutting is usually used in whole volume quenched state for secondary hardness. Using high-energetic sources like electron beam or laser is possible repeated surface quenching of chosen surface localities with complicated geometry. The treatment leads to local hardness improvement which results in local wear damage decrease.
Delivered specimens were surface quenched using electron beam technology. The paper deals with influence of individual technological parameters of the treatment on final properties of treated localities. Final properties of treated surface were examined by light and electron microscopy and microhardness testing.

Parametric modelling based on mathematical relationships allows creation of different variants of proposed solutions in real time. In particular, parametric modelling enables rapid design of 3D virtual models intended for further analysis and simulations. This paper presents an approach to design of a six strand wire rope model in a CAD environment. The presented model is characterized by double helical winding wires. Wires axes curves are mathematically expressed in the form of parametric equations. The parametric equations used in model generation are presented and the whole methodology of rope model creation in CATIA V5 software is briefly described.

In the aerospace industry, the nickel-based superalloys are often used due to their ability to withstand extreme conditions. They find their use particularly as turbine blades in jet engines. An important example of this type of superalloy is INCONEL. This construction material must meet a wide range of complex requirements with regard to its properties and technological and operational characteristics that are required by the heavy duty in extreme conditions.
The INCONEL Superalloys represent multicomponent and multiphase materials with their complex alloying base and structure with distinct dendritic segregations. Their long life and reliability in operation are directly related to the microstructure, or to its stability in a long-term operational application, respectively.
The presented work deals with the evaluation of microstructural parameters at two variants of cast superalloy INCONEL 713LC, applying the light microscopy and electron microscopy, including the fractographic analysis.

This paper deals with possibility of changing of shape of iron based phases in the secondary alloy AlSi7Mg0.3 microstructure by heat treatment. The Al-Si alloy usually has some other coexisting elements such as copper, magnesium, manganese, zinc, and iron. The solubility of these elements in aluminum usually increases with increasing temperature. This decrease from high concentrations at elevated temperatures to relatively low concentrations during solidification and heat treatment results in the formation of secondary intermetallic phases. For instance, the precipitation of Si, Mn, and Fe forms an Al12(Fe,Mn)3Si phase. The wide variety of intermetallic phases in aluminum alloys occur because aluminum is highly electronegative and trivalent. The main attention of this research is paid on possibility of changing the shape of iron based particles with heat treatment and on using heat treatment together with iron corrector. Realization of experiments and results shows new view on effect of heat treatment on iron based phases in castings with higher iron content.

The product price consists from several items. Time needed for adequate control of product is one of the most significant items, which can get expensive. So it is important, how the measurement strategy (measurement plan) is prepared. Time, which is not used for control of products by 3D measurement machine, is financial loss for company. This article deals with simulation of contact measurement, as a progressive tool, for preparation and creation of measurement plans for 3D coordinate measurement machines. Furthermore, the article deals with factors, that are not taken into account by offline programming during creation of measurement plan. Those can ultimately lead to significant difference between measurement simulation and measurement performed in workspace of measurement machines or CNC machines. This difference can cause serious shortcomings in measurement plans created in offline programming modules.

The article presents results of research in the field of prototyping - 3D printing. The authors are focused on polylactic acid material known by the abbreviation PLA, which is widely used in 3D printing method to produce objects. The tech-nology of successive layering of plastics and its solidification causes states of tension in printed objects and subsequently their deformation. That may even lead to torn the object from the print pad. The article deals with dimensions of the deformations at the specimen just in dependence on heating of the print pad. The authors also suggest a compromise solution between excessive deformation of underlying layers and therefore proportional change of physical dimensions of the object and low adhesion of the object to the underlying heating bed, which can be seen as cut off the object during the printing process as mentioned.

This paper deals with detection of surface burn after grinding operations on bearing rings made of case - hardened steels. The paper reports about Barkhausen noise technique employed for non destructive monitoring of grinding burn and discusses the main aspects affecting the Barkhausen noise emission such as thickness of heat affected zone, micro hardness, stress state, carbides, dislocation density and volume of retained austenite. Results of experiments indicate that the influence of stress state on Barkhausen noise is only minor whereas influence of structure features dominates. On the other hand, it is difficult to unwrap influence microstructure features contribution to the Barkhausen noise. For this reason their influence should be studied on the model surfaces undergoing the different regime of chemical and heat treatment.

Solid Rocket Motor (SRM) is a key component for the missile and space rocket. Sealing performance is an important index for SRM assembled. It is a necessary condition for study on the sealing performance of SRM to determine the residual stress of sealing ring which is difficult to be obtained by direct detection in engineering practice. This paper derives the quantitative expression of the relationship between residual stress, pressure difference and preload stress and establishes the method of determining residual stress of sealing ring by mechanical analysis. With the help of experiment, verify the correctness and applicability for expression meanwhile, analyze the influence of SRM's types and rubber sealing ring materials on residual stress changed under the effect of pressure difference. Therefore, the method of residual stress determined provides theoretical support to improve the SRM assembly process and lays a foundation for later study on the leakage rate of SRM.

From the technological viewpoint, the manufacture of forged parts is a very complex process governed by countless interrelated factors, the most important of which include temperature profiles, and magnitude and velocity of deformation. For a forge shop, a well-established and optimized forging process guarantees sound profit. Given the changing demands of the market, the range of products and the associated manufacturing parameters must be updated frequently and rapidly. In most cases, this means production line stoppages and production capacity losses due to new process development and optimization. Using material-technological modelling, it can be carried out in laboratory conditions instead, without interfering with the production. In this paper, several optimization experiments based on material-technological modelling are evaluated using various optical and electron microscopy methods.

The article defines the specifications of engine oils used alternative fuels. Used particle analysis of exploited oils gives the results of the wear mode, which indicates the ratio of large and small wear particles contained in exploited oil. Another very important result is defined as the level of wear, which indicates the amount of wear particles contained in exploited oil. For the level of wear Thin Layer Chromatography was used. It was possible in practical terms to apply discriminant analysis based on the results of these tribodiagnostic methods. Nomogram the wear receives practical information of current oil and engine wear. On oil life and operational reliability of gas engines affected by the choice of oil, according to the specifications. Another parameter is the mode of operation of the engine and preventive maintenance. The results of the oil wear were significantly different and depended just on the current state of the engine. For engines in perfect condition low values of wear were measured, for engines in poor condition critical wear was detected.

Numerical simulation of technological processes enables their exact description and it makes possible to get closer to the real process courses. The described method uses mathematical models transformed into the finite element method. The processes of interaction of the laser beam with the surface of austenitic stainless steel are first observed on simple geometrical models. Hereby the basic parameters of the processes are analyzed, and individual welding stages are described as dynamic fluid systems, in which steel is in a liquid state and it behaves as an incompressible fluid, while it is simultaneously loaded by the heat flux from the laser beam. Subsequently, three-dimensional models are analyzed using thermal and structural elements. Due to the high density of heat flow in the material, an orthotropical material model with equivalent coefficients of thermal conductivity of steel has to be used. The results obtained by numerical analyzes represent a sufficient picture of the behavior of the material when exposed to the laser beam, and they show the distribution of temperature, velocity and stress fields during welding. The acquired knowledge can be suitably used both in the automotive industry and also in many other industry branches.

NiTi alloy exhibits the shape memory effect, which implies the application in medicine and also many industrial branches. This paper is devoted to the manufacture of these alloys by the use of powder metallurgy using reactive sintering. This method could enable easier production of this alloy and achievent of higher purity. However, for the optimization of this technology, the deeper knowledge of the mechanism of the process is needed. This work uses microscopy on real powder mixtures subjected to reactive sintering, as well as on model samples processed under various conditions.

The article will describe investigation of the deformation of stainless steel during three-point bending cyclic loading with using thermovision. The analysis will prove different temperature response to external loading and dependence of elastic or plastic deformation development on material's state. The input data which are necessary for this analysis we will can get from temperature field of specimen surface. Process of elastic and plastic deformation is in dependence on radiation emitted by the object. For obtain thermal fields we will use thermal camera FLIR SC7000 with the highest sensitivity. The contribution also presents results of fatigue resistance of austenitic stainless steel AISI 316L, which is used as a biomaterial, obtained at low frequency cyclic loading in the high cycle fatigue region by three-point bending test. The fracture surface of the testing sample was examined using scanning electron microscopy (SEM).

The current paper summarizes briefly the results obtained by comprehensive investigations of magnetron sputtered Cr2N thin films with small additions of silver, whereas the pure Cr2N is used as a reference material. The main aspects reported here are: growth rate of the films, their growth manner, phase constitution, mechanical properties being represented by Young modulus and nanohardness, adhesion on the substrate made from Cr-V ledeburitic steel having a hardness of 60 HRC, tribological performance and effect on the mechanical properties of the substrate.

Hard inorganics microparticles are added to the composite systems due to optimization of some mechanical properties among which is possible to rank hardness and resistance to abrasive wear. Advantage of interaction of metal powders with polymers is also their ferromagnetism which changes physical properties of resulting composite systems. This paper is focused on evaluation of mechanical properties of epoxy resin filled with microparticles on the basis of iron powder (20.6 μm), mainly on resistance to abrasive wear, hardness and on adhesive and cohesive characteristics. The experiment evaluates composite systems prepared without using controlled semi-layers and without using a vacuum technology. Such technology was chosen with regard to practise. It is possible to consider the adhesive and cohesive characteristics as key properties determining possible application areas of filled reactoplastics. For evaluation of fracture areas was used electronic microscopy. The experiment confirmed significant increase of resistance to abrasive wear with increasing concentration of iron powder. This property can be utilized in widening the application areas of reactoplastics resins, i.e. creating the new resistant layers.

Presented research paper deals with possibilities of replacement of conventional mold materials by new, unconventional. Traditionally, laminate, wood or gypsum molds (in the case of small production series) are used for the production of composite parts. Furthermore, milled aluminum molds are conventionally used only for mass production. Due to this, thin metal sheet was prepared as an unconventional production mold for manufacturing of motorbike facing part. Vacuum bagging using prepared one side mold was chosen as the most appropriate technology. Normally, two facing sides are not commonly manufactured using this technology. Because of this, possibilities to create two facing sides at areas that are not in contact with mold itself were investigated. Presented results can help manufacturing companies with their production and considerably decrease manufacturing costs due to not necessity to use two side molds.

Hot tearing during solidification of aluminium alloys castings can be a serious problem. This phenomenon is well known but still insufficiently investigated. Hot tearing occurs in form of irregular cracks in metal castings that develop during solidification and cooling (typically while the casting is still inside the mold or die cavity). The cause of hot tearing is generally attributed to the development of thermally induced tensile stresses and strains in a casting as the molten metal contracts during solidification and solid state shrinkage. Submited paper consists of two parts. The first part introduces the reader to the phenomenon of hot tearing. The second part describes newly developed method for assessing hot tearing susceptibility of aluminium alloys, and also gives the results on hot tearing for various aluminium alloys.

Process stability is one of the factors determining high quality of the products. By stable process, operations conducted in order to produce a given product are repeatable, and at the same time products manufactured in such process are repeatable and theirs quality is predictable. In the article the BOST method was used to evaluate casting process stability. The research in from of a survey was conducted in one of the Polish foundry. The results were presented in form of 2x2 matrix. This matrix has two variables: process stability (X axis) and product quality (Y axis). Employees quite highly evaluated the process stability, and medium and low product quality. Which means that the research foundry is located in the B zone of the map of process stability, which is referred as "Fundamental changes in the process".

The subject of this study is the analysis of vibrations induced during milling of a thin-walled element. The milling was performed with a 2-flute custom end mill for machining Al alloys (FENES, 12x22x80-45°W-Z2), diameter d=12 mm. The rectangular 7075-T651 aluminium alloy workpiece of the following original dimensions: 120x60x12, was machined in a DMG MORI DMU 65 MonoBLOCK 5-axis milling machine. The vibrations of the aluminium alloy test plate were identified with Siemens LMS Scadas Mobile system and LMS Test Lab software. A PCB Piezotronics triaxial ICP accelerometer (model 356B21), offering sensitivity of 10mV/g, was employed. The sampling frequency was 11.5 kHz. The first stage consisted in measuring the vibration levels of the sample, in the function of its thickness and federate vf, at constant technological parameters of machining. The feed vf was set to 1500, 2000, 2500 and 3000mm/min, the depth of cut ap =2mm, the cutting speed was constant and equal to vc = 150.7 m/min (n=4000rev/min). The wall thickness b of samples was equal to: 30mm - reference sample and 11, 9, 7, 5, 3mm - test samples. The vibration signal was measured by two sensors attached to the surface of the sample in two extreme positions on the sample: point P1 and point P2.

This study was focused on the analysis of creep behaviour of the polymer composite with continuous phase in the form of two-part epoxies and discontinuous phase (reinforcing particles) in the form of fibres of false banana (Ensete ventricosum). The aim of the experiment was to describe the short term flexural creep behaviour, flexural strength and Charpy impact strength of polymer composite reinforced by fibres of false banana. The fibres of Ensete ventricosum, originally from Ethiopian region Hawassa, were used for this experiment. Reinforcing fibres were prepared in size of length 1-2 mm with randomly fibres arrangement in matrix. The amount of reinforcing particles in the composite material was 0.5; 2 and 30 wt.%. Moulds for casting specimens were produced from the material Lukapren N regarding to the prepared models whose shape corresponds to the technical standard CSN EN ISO 3167. Composite which was used to prepare specimens according to CSN EN ISO 3167 (Plastics - Multipurpose test specimens, English Standard Institution) was created by mixing of fixed rate of matrix and filler.

The occurrence of any cracks or defects in car body parts processed by deep drawing technology is not allowed by high quality standards. This kind of defect is considered as the most dangerous for the process quality and stability because it cannot be easily detected during the manufacturing in the steel plant and also in final inspection after pressing, that's why the occurrence of these defects has always to be studied in detail. For the prevention of defects, it is necessary to study the deformation behaviour of the material in the immediate vicinity the crack tip in detail. For the study the controlled scratched samples were tensile deformed and then were studied using UHR-SEM equipped witd EBSD detector. The EBSD technique allowed detailed inspection of the effect of deformation on the grain structure as changes in grain orientation or local crystal lattice missorientation and thus directly observe and evaluate both, elastic and plastic strain. Obtained results showed that the scratch does not affect deformability of the DC06 deep drawing sheet negatively due to too large tip radius with respect to low sheet thickness.

The correct determination of the shelf mass including content is very important for the proper function of a universal shelf stacker (USS) drives life and construction USS so that these elements were not overloaded. Weighing can be done by direct methods using various sensors tension and compression but also the indirect method, by the torque sensing of current frequency converter, which controls the speed of the three-phase asynchronous motor. This method does not require any additional construction or adaptation or additional sensors or electronic evaluation system power operation. Weighting method of shelf in USS is based on the fact that the torque converter current is proportional to the sum of the weight of the shelf and the extractor and its value provides almost every frequency converter. In contrast to the direct weighing method of the shelf it is obvious economic advantage of this method and the accuracy is sufficient for the operation of USS.

In this work, the influence of alloying element in equimolar Ni-Ti alloy was investigated. Selected alloying elements (cobalt, chromium, niobium) were added into Ni-Ti46 wt. % powder mixture. The samples were prepared by self-propagating high-temperature synthesis at temperature of 1100 °C with the use of high heating rate (300 °C/min). The changes in microstructure, phase composition, temperature of reaction between Ni-Ti-X powders, phase transformation temperatures and mechanical properties were studied.