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In the previous paper [12], a design of location and construction of a rotating turning tool has been documented. Sporadically, this tool has appeared in literature [1], [2], [3], [4] in different applications. So far its operational characteristics, mainly its considerable influence on machined surface quality, exceptional durability and possibility to be used to turn hard machinable materials have not been appreciated. Some of its priorities are verified in the paper.

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.

A composite is a material which is made up of two or more distinct materials. Composite materials are generally used for buildings, bridges and structures such as boat hulls, swimming pool panels, race car bodies, shower stalls, bathtubs, storage tanks, imitation granite and cultured marble sinks and counter tops. As a result of absorption of liquids usually occurs a change in volume, which is referred to as swelling. This process can give rise to physical and chemical properties of polymers.NIS - Elements 3.0 was used to evaluate the microstructure of composite materials with different contents of ferrite powder filler. Using NIS - Elements 3.0 assessed the number of particles Sr ferrite surface area and perimeter Sr ferrite particles and the volume fraction of Sr ferrite in the microstructure.

Article is focused on detection internal residual stress caused by machining with variant spindle speed of milling tool and also in the article is represented new method of residual stress measuring using by ultrasound with verification method using RTG diffraction. Effect of residual stress have in industry important place because large number of structures requires a clearly described process of the occurrence and intensity of internal residual stresses, which directly affect the quality and equipment life. Nowadays are mostly used destructive methods, which can occur changes in functionality of the products or non destructive methods are used, which require to measure residual stress outside of the workplace and those methods are often lengthy. In the article is presented new method base on ultrasound, which provides opportunity to measure residual stress in same place in a short time.

Equimolar NiTi alloy known as Nitinol, is a modern metallic material on which very high demands are placed. This alloy has been used for its unique properties, such as shape memory, superelasticity and pseudoplasticity. Nitinol also has very good corrosion resistance and applicability as a biomaterial. In medicine Nitinol is most often used in the form of stents, which are used as reinforcement bottlenecks in the cardiovascular system or gastrointestinal tract, ortodontistic wires, orthopedic terminals of micro invasive surgery tools, tools for endoscopy and apertures or aneurysms. Successful use is subject to a manufacturer's declared stable mechanical properties of Nitinol. These properties can significantly influence a hydrogen deposited in the alloy, both due to the manufacturing process itself so that the resulting exposure in the environment. It was shown that even very low contents of hydrogen in the alloy leading to a substantial reduction in plasticity and strength of Nitinol which may be one of the main causes of premature failure of medical implants in the specific environment of the human body.

The article deals with the determination of the life of the lubricant based on the determination of the degree of wear or deterioration of the engine oil by wear particles. Non-ferrous particulates of a large diesel engine and their determination based on laboratory tribotechnical diagnostic tests are characteristic for the purposes of article. The combination of Atomic Absorption Spectrometry and Thin Layer Chromatography is used for measurements. The statistical method of discriminatory analysis is used to evaluate the article. The lifetime of the lubricant is thus determined according to objectively determined criteria realized by normalized and customized analyzes of the lubricant at a high degree of accuracy. The proposed and verified method demonstrates the degree of achievement of individual lubricant wear limits of non-ferrous metals in a large compression-ignition engine. The clear advantage of the proposed method is the precise determination of the optimal oil change interval and the possibility of early detection of a vehicle defect.

This paper describes the conception of vehicle interior which can help decrease the injury risk of unbelted passenger. This paper is primarily aimed to the field of rail vehicles, but the results are useful for more transportation industries. Some computer simulations for passive safety performance assessment were conducted in previous years. The FE models of the interiors based on data from actually operated vehicles were prepared for this purpose. The newly prepared simulations are close to the real interior models. Combinations of rigid walls were used for modelling. Each model contains a short python code which allows change of interior disposition. This approach is close to an optimisation process. The main goal is to compare all possible configurations of interior. In practise it is usually obvious which change can improve the passive safety, but with numerical approach is possible to find structures with unknown influences. The simulations were performed in software environment PAM-CRASH. It is used a dummy Multibody model of the human body ARB Hybrid III 50th percentile.

Equal-channel angular pressing is a method of severe plastic deformation, which implies high deformation into the material and leads to grain size reduction and strength increase. It was applied on a twin-roll cast Al-Mg-Sc alloy, which contained Al3(Sc,Zr) particles formed during annealing at 300 °C for 8 hours. The evolution of the microstructure and mechanical properties after deformation was studied during isochronal heating 50 K/50 min. Strengthening occurred during annealing at lower temperatures and was followed by prominent microhardness drop, which was connected with formation of new grains and recrystallization. The presence of Al3(Sc,Zr) particles in the matrix is accounted for the high temperature stability.

Nowadays, foundries do not sufficiently utilizes computer support during the creation of technical documentation. Instead of computer documentation, foundries are using classical method for designing technological documentation and the computer aid is only discrete. For the area of foudry technology, it is inappropriate to use conventional CAPP systems which use group technology because they work with a simple representative selection from the database according to the characteristics. The submitted article shows a solution for systems interconnection and the possibilities of using the simultaneous engineering for aircraft industry. A new system was designed serving as the creation tools for technological documentation, whose role is to effectively benefit from group technology with use of latest software capabilities.

This work deals with optimization of Spark Plasma Sintering conditions for the preparation of Ti-Al-Si alloys. Ti-Al-Si alloys are appropriate material for high-temperature applications, especially for aerospace and automotive industry. They are characterized by low density, good mechanical properties and resistance against oxidation. Ti-Al-Si alloys were prepared by powder metallurgy using reactive sintering, followed by milling and Spark Plasma Sintering. Preparation of intermetallic compounds is complicated due to high melting points of intermediate phases, the exothermic reaction during their formation and high reactivity of the melt with melting crucible. TiAl10Si20 alloy was prepared by Spark Plasma Sintering under a pressure of 48 MPa and by High Pressure Spark Plasma Sintering under pressure of 6 GPa. The temperature was chosen between 1100 °C and 1204 °C. The porosity of TiAl10Si20 alloy decreases with pressure and with the high pressure also increases the hardness by 200 HV 5. Abrasive wear resistance of TiAl10Si20 alloy is very good.

This article offers completely new results in the research of NiTi alloys produced by Self-propagating High-temperature Synthesis (SHS). There is investigated the effect of addition of magnesium on the microstructure, phase composition and especially, the amount of undesirable Ti2Ni phase. This phase is unwanted in NiTi alloy because of its brittleness. Moreover, this one is stabilized by oxygen and forms during SHS process. Selected preparation method is considered as an alternative to the melting metallurgy, which produced products with poor homogeneity and purity. For this reason, SHS process has been studied intensely and many researchers have tried to eliminate secondary phases unsuccessfully. Our research showed that alloying by element with high affinity to oxygen causes disappearance of Ti2Ni phase.

The article describes the possibilities of vehicle passability testing by the help of computational simulation. It is used here computing simulation system ADAMS AVT. The simulations can help to find quick answers to basic and additional questions of design change influences in the area of testing vehicle passability. The first part of the article contents description of partial computation simulation models construction which the calculations are associated with. There are mentioned the binding conditions of calculations also. There are mentioned and evaluated the results of performed simulation calculations in the second part of the article. These calculations are performed in order to find out an influence of operation conditions on the vehicle passability. Real operation condition is invasive vehicle speed into a slope in this case. Under investigation are the changes of beaten distance uphill that is the vehicle able to overcome.

In this paper, the effects of carbon nanotubes on the mechanical and electrical properties of cement-based composites at different ages have been studied. The structures were characterized by SEM. The experimental results show that the higher content of carbon nanotubes may enhance the strength, when the content of carbon nanotubes is 0.1%, the 3d flexural strength increases about 60.6%, 28d strength increases about 57.4%, the 3d compressive strength increases about 33%, 28d strength increases about 11.6%. Highly dispersed carbon nanotubes can form uniform network structure in cement paste, so the mechanical properties of composites can be greatly improved. The conductivity of specimen increase with the content of carbon nanotube increasing, but decline as the content is more than 0.1%, the rate of decline is slow. Carbon nanotube is conductive, they superpose each other and form the conductive network, which can make the cement based material capable of conducting. SEM pictures show that dispersion of the carbon nanotubes in the cement matrix is difficult when the content is more than 0.2%.

Article deals with design of welding jig for assembly of wind power plant component. Mainstay of article is design of welding jig, which makes exactly setting and reliable clamping of individual parts of welded desing possible for their complete welding. Design procedure of individual parts of welding jig is described in details in view of their functionality. Paper is especially focused on the parts of welding jig, which are necessary to make, including material selection of individual parts. Finally the technical and economic evaluation is carried out, approximate cost of jig is calculated and financial savings associated with practical use of welding jig are evaluated.

The purpose of this paper is to provide an overview of state-of-the-art of maintenance management audit and to show a case study of maintenance audit and its results in the Czech Republic. Authors proposed audit methodology based on world and own experiences. It was defined hundred thirty audit criteria divided into ten maintenance management areas. Using expert approach to review of maintenance managers and documentation according to audit criteria enables to obtain answers and their assessment presented in percentage of audit criteria fulfilment. After that there is applied SWOT analysis method to determine mainly weakness (gaps) in real maintenance management processes comparing with world excellence maintenance class. On the base of the gaps there are recommended topics for maintenance improvement. Value of the results is a help to maintenance managers and supervisors in maintenance audit executing as a tool for maintenance management improvement.

This paper presents an improvement to the mechanical and tribological properties of aluminium alloys. AlSiN and AlCrSiN coatings (with different Cr content) were deposited on substrates of Al-Cu-Mg alloy by the cathodic arc evaporation method at 400°C. Surface morphology and chemical composition were estimated by a scanning electron microscope equipped with an energy dispersive spectrometer and mechanical profilometer. The increasing chromium content in the coating led to an increase in the coating hardness. The tribological behaviour of the coated and uncoated Al-Cu-Mg alloy samples was examined using the "Ball-on-Disk" method (ASTM G99-95) at a load of 10N using Al2O3 ball as a counterpart.

The Al-20Si-16Fe alloy (wt.%) was prepared by a combination of short-term mechanical alloying and consequential compaction via spark plasma sintering. The compaction was done at two different pressures of 80 MPa and 6 GPa to describe the influence of pressure onto a resulting properties of prepared alloy. The microstructure of both the prepared compact alloys showed presence of sub-micrometre particles embedded in the Al-matrix while some residual porosity was also observed. This corresponded to the lower compaction pressure of only 80 MPa, which, in comparison to the 6 GPa allowed to retain some porosity. The higher compaction pressure of 6 GPa resulted in a increase of the compressive strength of 1426 MPa while the hardness was slightly lower reaching still high 348 HV 5. On the other hand, the sample compacted by a pressure of 80 MPa reached compressive strength of 758 MPa while showing higher hardness of 411 HV 5. The difference in the observed properties can be attributed to a different compaction temperatures of 500°C (for 80 MPa) and of approximatelly 600°C (for 6 GPa).

Paper is interested in the study of basic theoretical knowledge from the problems of preparation of nanoparticles and microparticles and their mechanical synthesis. Also, the possibility of producing of new materials by mechanical alloying of metal powders evaluation of these newly created materials from the point of morphology and surface condition, as well as physical (eg. electrical charge) and chemical (surface treatment).

The quest for light and stiff structures by industries such as the medical industry and the aerospace industry is the driving force behind developments in additive manufacturing technology. One way to achieve significant weight reduction of components is by deploying periodic porous structures. Various types of porous structure geometries use material with varying efficiency, and therefore vary in their resulting mechanical and physical properties. This article focuses on the lightweight Schoen Gyroid cellular structure, which could offer a suitable combination of the desired mechanical properties. The goal is to determine the effect of the volume fraction on the load capacity of the gyroid structure made of maraging steel using DMLS technology. We conclude from the experimental measurements that the results could be affected by several factors, which are detailed at the end of article.

Under isothermal treatment conditions, bainite transformation involves decomposition of austenite into a nonequilibrium structure consisting of needles of super-saturated bainitic ferrite and carbide precipitates. Similarly to martensitic transformation, bainitic ferrite forms by shear mechanism. Owing to relatively low temperature, only interstitial elements, predominantly carbon, can migrate by diffusion. Depending on the transformation temperature, carbon migrates from ferrite and forms carbides, either within bainitic ferrite needles and at the interphase interface between bainitic ferrite and austenite, or only within bainitic ferrite needles. In conventional steels, bainite transformation continues until the decomposition of austenite phase is almost complete. If the steel contains enough silicon, carbide precipitation may be suppressed or even prevented altogether. In such case, carbon which diffuses from the needles of bainitic ferrite may enrich adjacent austenite areas. Depending on heat treatment conditions, the carbon-enriched austenite may become sufficiently stable to resist decomposition and remain in the microstructure.

The article deals with testing of the resistance against Foreign Object Damage (FOD) on leading edges of blisks (blade disks) in turboprop engines made of Ti6Al4V alloy. Such damage can occur during operation, when rapidly rotating compressor parts on the engine intake are exposed to foreign particles. E.g. operation of small passenger aircrafts in desert areas, where large amounts of foreign particles occurs in the atmosphere. The paper describes the development of method for testing the resistance of the leading edge of the blades against FOD in order to mimic the conditions of operational damage. Further it quantifies potential benefits of modification in the geometry of the blisk leading edge and compares results of FOD resistance of sharp leading edge and modified geometry. Results of metallographic analysis for deformed areas near the FOD on Ti6Al4V alloy are also presented.

An article deals with a production of a planetary mechanism model prototype using an additive method of Rapid Prototyping (RP) by a 3D printer called uPrint. The first part of the article contains a theoretical analysis of a main principle and kinematics parameters of the planetary mechanism model. The second part begins with an experimental analysis of a planetary assembly calculation and continues with a description of a production process of all individual mechanism parts and description of the final completing of the planetary mechanism prototype. The final part deals with a characterization of ABS styrene polymers generally used for production printed by uPrint device.

A method of 3D scanning and a subsequent data reconstruction presented in this paper are focused on digitization of highly structured composite parts with regard to creation of a fully functional CAD and FEM model. The digitized parts are structured carbon composites made replication of steel templates. Production of steel templates is a technological procedure mostly based on pressing or rolling. However, the data obtained from 3D scanner are not in appropriate format, there are a cloud of points interleaved by a sufrace and it is necessary to use some aditional methods to solidify the resulting geometry. Most often with using commercial software as for example: Creo, Catia, Inventor, Rhino or Geomagic studio is the cloud of points parameterized in a continuous surface. Now, based on some next operations (intersections, blends) the desired solidified model in CAD format could be achieved. Despite the relatively rapid creation of the main shape the minor inaccuracies that occur during non-contact measurement results either in local areas or individual points with a large deflection. The aim of this thesis was to assess the appropriate method for creating geometry and compensation the inaccuracies with regards to numerical simulations, especially the meshing and convergency of a solved model. As has been quite surprisingly found, some local small step changes in the geometry could be for the calculation easier to solve than a complicated and highly approximated area. An influence to a solution does not seem important.

This work deals with the problematics of cutting forces when drilling holes in Inconel 718. Drills with different geometries of cutting edge were used. The cutting forces and torques were measured during the experiment. The feed cutting force had the greatest influence of all the cutting forces, therefore only the cutting force feed was evaluated. The torque was monitored. This material is known for its unique properties of high strength at high temperatures, corrosion resistance, high hardness, work hardening and low thermal conductivity. Part of the paper is focused on the experiment where the effects of the geometry of the cutting edge on cutting forces are evaluated. This paper is limited only to carbide tools. The results of the experiment are compared with results from other research institute.

Machining of titanium alloys meets with poor life of a cutting tool. It is caused by a low thermal conductivity and by a high strength-to-weight ratio of the alloys. Various approaches for cost-effective and productive machining titanium alloys are still researched. One of methods can be using the cutters made of modern high-speed steel (HSS) as a product of a powder metallurgy (PM) process. These materials (PM-HSS) possess better and homogenous mechanical properties than conventional high-speed steel. The PM-HSS cutters equipped with any effective coating allow increase cutting speed to the level which is typical for uncoated cemented carbide, while price of the tool is lower. In the article several PM-HSS cutting tool materials were compared to conventional cobalt based HSS from the tool life point of view. It was proved that conventional high-speed steel offers very long tool life and high tool performance at speed of 30 m/min. However the regular tooth pitch significantly decreases tool life for this cutting tool material. The main benefit of PM-HSS cutters can be fully utilized when cutting speed about 50 m/min is applied. The cutters coated by effective thermal barrier showed longer tool life and higher performance of the cutting tools.

This paper is focused on hazards in milling processes. It continues in occupational health and safety in turning. Safety rules are based on general rules and specific ones which relate to milling. It is necessary to formulate hazard and safety rules more precisely for specific production processes and in some cases for different production machines. For satisfactory solution of this problem the rules are formulated on the base of laws, regulations and personal findings of the paper's authors in enterprises. In the paper occupational health and safety hazard rules in milling on these principles are formulated.

This paper considers the assessment of attenuation in aluminium alloys castings prepared by gravity casting method and under pressure. The issue of ultrasound attenuation is important in setting the conditions of non-destructive testing, especially in casted materials. The characteristics of the ultrasonic technique, the calculation of the attenuation and the velocity of ultrasound are presented in the theoretical part of this paper. For experimental measurements, cylindrical castings from AlSi alloy were made. The ultrasonic records of the casting control, the calculation of ultrasound attenuation for individual samples as well as the microstructures are listed and described in the experimental part. The evaluation of measurements and comparison of calculated ultrasound attenuation is at the end of this article.

Polymeric materials are thanks its processing and utility properties materials in demand of common and special use. They are also largely replacing conventional materials. As the popularity of polymeric materials grows, also the amount of its waste increases. For this reason, there is introduced the term recycling as a method of processing, re-use of the waste, into technologies of polymeric processing. So, this paper deals with the possibilities of introduction of recycled material. The main part of this paper is created by an experiment that explores the changes of tensile properties of test specimen according to the selected percentage of additives in the volume of the basic granulate. The test specimen was produced by mixing pure granules with the addition of recycled and re-granulated materials. The conclusion of this work presents a comparison of the results of each tensile test that provide an overview of the behaviour and properties of the materials tested.

An important factor in enhancing the mechanical properties of high-strength steels is the stabilization of an appropriate amount of metastable retained austenite in martensitic matrix. Various novel heat treatment and thermomechanical processing routes have been developed recently which benefit from the effects of retained austenite in terms of achieving better elongation at still high ultimate strength levels. One of these procedures is the Q&P process (Quenching and Partitioning). It produces martensite and retained austenite to obtain strengths of more than 2000 MPa and elongation levels of about 10%. For this investigation, four steels with low Ms temperatures have been selected. Their chemistries contained manganese, silicon, molybdenum and chromium.The development of heat treatment sequences involved trials with various austenitizing temperatures, cooling rates, quenching temperatures, and carbon partitioning temperatures for the stage in which austenite becomes stabilized. The experimental heat treatment led to microstructures consisting of martensite with retained austenite in all the steels. Their strengths were in the range of 1750-2400 MPa and their A5mm elongation was 10-15 %. The largest fraction of retained austenite, according to X-ray diffraction, was 10 %. Specimens with the largest fraction of retained austenite obtained from one schedule were used for studying the stability of retained austenite under cold and hot.

During the cold form tapping process of internal thread in high-strength-steel, the effect of bottom-diameter, extrusion speed, friction factor and extrusion times on extrusion temperature and torque have contributed to tap wear, break and manufacturing quality. The process of cold form tapping of internal thread for Q460 high-strength-steel is studied through numerical simulation and experimental research. The effect of different processing parameters, including the bottom-diameter, extrusion speed, friction factor and extrusion times, on temperature and torque during the process of cold form tapping of internal thread are analyzed to provide new basis for further choosing optimized processing parameters. The simulation and test results show that obvious stress-strain and higher temperature zone focuses on working area during the cold form tapping of internal thread for Q460 high strength steel. The simulation value is slightly lower than the measured value and the error is no more than 20%. With the increase of bottom-diameter and extrusion times and the reduction of extrusion speed and friction factor, the extrusion temperature and torque will decrease.