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New types of process fluids is very broad. Drilling with constant feed force represents the experiment that follows different properties and effects in machining. The main aim of this scientific paper is to assess the speed of drilling holes by the drilling technology-constant feed force- with the drilling cutting tools made of uncoated high speed steel. Eleven different process fluids were compared used the during the experiment. There were compared eleven different process fluids. In the context of the thesis more process fluids from global suppliers have been tested. In the process of experiments there were used twist drills of high speed steel type HSS, ČSN 221121, ø 8 mm, without coating. Steel samples were 16MnCr5, according to EN 10084-94. During the experiment there was used drilling of holes by hand feed drill machine V 20 that was modified with the mechanical switch and there was also stopwatch. Testing of process fluids in chip machining has been going on at the Department of machining and assembly of the Technical University of Liberec for many years.

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.

This paper focused on axial flow pump high operation, reliability, and long service life at different frequency of rotation (DFR). The efficiency of an axial pump varies considerably depending upon the conditions under which it must operate. This article concentrates methods related to the reliability analysis of pumping system operation by a frequency converter. Initially, it is focused to analyze the behavior of individual characteristic curves of the axial pump to find how can be applied for the determination of the most efficient frequency of rotation. Axial flow pumps are often controlled by adjusting their rotational speed, which affects the resulting flow rate and output pressure of the pumped fluid. In addition, the head and flow of fluid transported at different frequencies of rotation, to produce a map of reliability characteristic curves to verify the similarity rules for pumps recommendable operating region are discussed. The results showed that the recommendable operating region for a different revolution per minute of axial pump can be determined with efficiency. If the axial flow pump is driven outside its operating region, the efficiency decreases, and the reliability and long service life may be affected.

Present work is focused on the study of recycled AlSi8Cu2Mn cast alloy. Furthermore, the effect of Sr-modification (0; 0.03 and 0.05 wt. %) on the microstructure, tensile and impact properties (UTS, ductility, hardness and impact energy) were investigated. For study and identification of intermetallic phases were utilized standard, colour and deep etching (in order to reveal the 3D-morphology of the Si-particles and intermetallic phases). For element composition of the specimen was used X-ray analysis. Finally, the effect of Sr-modification on silicon morphology was examined. The results show that the addition of Sr into AlSi8Cu2Mn cast alloy should act as a modifier, so it supposes to change the eutectic Si-morphology. However, its effect as a Si-modifier is not as significant. Higher number of iron (1.1 %) leads to an increase of precipitation of brittle iron phases with platelets (Al5FeSi) and skeleton-like (Al15(FeMn)3Si2) morphology. Al5FeSi platelets act as preferred crack sites and reduce the tensile and impact properties. Strontium not only refined and modified eutectic Si, but also modified the Al5FeSi needles and thereby improves tensile (first of all ductility) and impact properties. Sr addition is also associated with porosity formation.

This work deals with the issue of tapping Inconel 718 alloy. This material is known for its unique properties of high strength at high temperatures, corrosion resistance, high hardness, work hardening and low thermal conductivity. The machinability of Inconel 718 is very hard and cutting tool wear is high.This paper deals with creating internal threads by using monoliths taps. The taps are made of powder metallurgy high speed steel.The taps were provided with coating. Preparation of the hole for the thread has a huge impact on the cutting tool life. If the preparation is poor the inner face of the hole will be work hardened. This makes the cutting tool life far shorter. For the test, taps with different threads per chamfer were used. The second part of the paper is focused on the experiment where cutting tool life was monitored.

The paper deals with welding joints and the methodology of increasing safety during austenitic chromium-nickel steels welding - type EN 10028-7 1.4301 (X5CrNi18-10). The technology of submerged arc steel welding 1.4301 using MAG enables a wider application of these steels in terms of the production of pressure vessels, but despite following all the safety regulations of heterogeneous welding stated in WHS, there might be an occurrence of melting defects of carbon parts through the welding of joints. The aim of this paper is to discuss the corrections of welding penetrations of the additional material during inhomogeneous welding, with the least possible destruction of the original material.

Although important improvements of prosthetic sockets has been implemented another investigation has been done also by solving problems with inadequate stump heating and from that resulting excessive sweating of limb. This phenomenon is further associated with leg volume changes. Therefore for realization of this research the model of prosthetic limb was created with socket that further addresses these issues of artificial limb. Throw the application of holes and tightening bells the pressure to remaining stump decreased and at the same time the heating of limb is lower. These results indicate that the implementation of these design modification will improve the comfort and fit of prosthetic devices in future.

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.

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.

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.

Fractographic methods derive their knowledge from Euclidean geometry, set theory, metric theory and chaos theory. In engineering technology, the fractography is primarily used for modeling of fatigue and intergranular fractures. As such defects are not smooth due the principle of their origin, they cannot be described using ordinary mathematical tools. However, if the conditions of self-similarity are met, fractal geometry means can describe various irregular, incomprehensible, crooked or fragmented geometric shapes. Fractographic description of the fracture profile allows more accurate quantification of fractures and it also enables identifying possible causes of their initiation. This study contains several examples of specific cases of Cr-Ni steel failures and a basic explanation of their fractographic description.

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.

This work deals with the problematics of 3D printing. Additive manufacturing (AM) covers a lot of principles of producing products and prototypes, for example, Direct Metal Laser Sintering (DMLS). This principle is based on sintering metal powder in thin layers, layer by layer. This theme is very extensive and a very popular research area. The paper is focused on printing thin walls. The material for printing was Maraging Steel MS1. This material achieves great mechanical properties like as high strength and high hardness. The tensile strength can be up to 2000 MPa after age hardening. The printer used was an EOS M290. The effects of different part position on safety of printing are compared. Also, the effect of support structures on accuracy was investigated. The main part of the paper is focused on an experiment where thin walls are printed and subsequently evaluated. The influences and limitations were investigated. The measurements were carried out on a Blickle Multicheck PC500 microscope.

Dimensional changes, or distortion, play a very important role in carburizing. To keep carburizing process productive and profitable, it is crucial that the resulting distortion is minimized. The purpose of this experiment was to carry out low-pressure carburizing and measure dimensional changes, residual stresses, characterize the resulting microstructures, and determine hardness in the specimens. These are the most important clues to the quality of the carburized layer. Experimental materials were the most widely-used carburizing steels: C15, 16MnCr5 and 15NiCr13. Residual stresses in the surface were determined by X-ray stress measurement.

The paper deals with a study of actuator (brake cylinder) modification for generation of braking force in a brake unit. The original solution, carried out using the original brake cylinder in cooperation with the proportional pressure control valve, is sufficient in terms of correct function of the brake unit, but in terms of safety, the corresponding force sensor may be damaged in case of a control circuit proportional pressure valves defect. Another reason for the study is utilization of the total regulation range of the proportional pressure valve and improvement of the brake unit response time in case of braking force overload. Such overload results in tread or rotating rail surface damage. The article gives description of the currently implemented passive measures to increase safety against sensors damage, but also of proposed active measures to eliminate these defects by changing size and type of the brake cylinder.

To design an optimal support of a large shade sail it is necessary to determine forces in wire ropes that support the sail. Relations between a sail loading and ropes reaction forces, rope diameters and sail stresses were investigated. To simulate the sail behavior and set up these relations, numerical (FEM) models were created and analyzed. Most of the results show nonlinear relations between above mentioned parameters and they depend on the sail geometry, applied loads and the rope diameter. It means that for every specific geometry and loading of particular sail an optimal rope diameter and support should be designed. The nonlinear numerical analysis is very suitable tool for this purpose and thus specialized systems based on the Finite Element Method (FEM) should be used to simulate and analyze such problems.

An article deals with an analysis of selected aspects of heat-treated bearing rings during machining and comes up with a solution (a machining operation) leading to improving efficiency of a machining process (i.e. an elimination of a generally expensive cutting technology when the same surface integrity is kept) lying in the series of samples that would be tested experimentally under university conditions (a workroom C2 of Department of Machining Technology FSI VUT in Brno) using a CNC turning lathe SP 280 SY.
A theoretical part focuses on a characteristics and analysis of a given component including an applied material 100Cr6 from which bearing rings are made. A practical part deals with an analysis and evaluation of a residual tension in a surface layer (Barkhausen noise: BN) using the device Rollscan 350. The article also comes up with a solution of an issue of surface integrity after a turning operation of bearing rings. The surface integrity is analysed with a touch measuring device (the device with an inductive sensor Form Talysurf Intra - Taylor Hobson) and a contactless device Talysurf CCI Life - Taylor Hobson.
The article ends with an analysis and evaluation of assessed aspects applied during turning of heat-treated bearing rings regarding the required workpiece quality.

The present paper deals with the metrology, especially with the legal metrology that is responsible for assuring the uniformity and correctness of measurements. In addition to the definition and explanation of the basic terms and principles applied in the metrology, the paper presents especially the results of the scientific and research work in the cross-disciplinary fields of the legal metrology in Slovakia, namely in design and realization of a new measuring system for the verification of the radar level gauges.

This paper deals with the assessment of the procedural gases progressive cooling methods and cooling by procedural liquids at turning technology on the final workpiece surface quality. Turning by using liquefied CO2, liquefied nitrogen and subcooled air supplied through the vortex tube was compared with the turning without process medium (taken as reference conditions) and with two procedural liquids EOPS 1030 and HOCUT 795 B. At evaluation effect of procedural gases there were monitored acting forces, cutting tool cooling rate and the machined layer of the material, cutting tool durability and cut surface quality which was characterized by surface roughness and dimensional accuracy. During the experimental part there were used devices as lathe SU50, piezoelectric dynamometer, the evaluation unit and profilometer. This issue was solved within solving the project TACR - TA03010492.

Titanium is widely used as biomaterial due to its excellent corrosion resistence, caused byTiO2 layer that is spontaneously formed on its surface, biocompatibility and good osseonitegration ability. To approach mechanical properties to human bone there is increase of using porous titanium. That form has lower density, causes better ingrowth of bone tissue which makes a strong bond between implant and bone. Porosity also decreases Young's modulus, which causes that the "stress shielding" is eliminated. New alloys based on titanium and silicon seems to be a perspective material for biomedical applications. This work is devoted to the optimization of the alloy composition and the addition of the pore-forming agent. It has been shown that this alloy can achieve the mechanical properties and microstructural features comparable with the human bone.

Not only engineering production at present is characterized by increasing an international competition. It is achieved higher productivity with simultaneous improvement of quality parameters of machined parts by using of process fluids. In other words, the use of process fluids positively improves and increases the both the qualitative as well as quantitative parameters of the technological processes. Process liquids in machining occupy an important place and influence the outcome of the all processes. Choosing a suitable process fluid should be carefully considered. It is well known that, different machining technologies have different cutting conditions and thus completely different requirements on process fluids. Selection of a suitable process fluid is more important that the management of manufacturing companies admits. Unfortunately, the selection of suitable process fluids is very often underestimated.

An article deals with a concept of increasing efficiency of a current production process of bearing ring machining. A goal is to substitute a generally expensive technology of cutting when at least the same integrity of a surface is kept. A theoretical part is focused on a characteristic and analysis of a given component including an applied material 100Cr6 from which bearing rings are made. A practical part analyses and suggests an innovation of increasing efficiency of the machining process. Series of samples would be tested experimentally at university conditions (Workroom C2 of Dept. of Machining Technology, Faculty of Mechanical Engineering, Brno University of Technology) using CNC Lathe Machine SP 280 SY.
The article describes individual production workplaces along with used tool equipment that includes for the process of increasing efficiency the innovation in the form of the change of the production process, changes of most cutting tools and cutting conditions needed for the turning of heat-treated bearing rings. The article also deals with a surface integrity after turning of bearing rings. The integrity is analysed using a touch measuring tools (a manual roughness tester TS100, a tool with an inductive sensor Form Talysurf Intra) and using a touchless measuring tool Alicona Infinite Forces G4, including the measurement of a residual tension in a surface layer (Barkhausen noise) by the tool Rollscan 300.
The article finishes with a wear test of replaceable cutting blades at applied cutting conditions with a follow-up discussion, which describes problematic steps that were done in particular phases of experimental testing, and with necessary concept of further testing of bearing rings.

The paper deals with the lead-free soldering and influence of germanium amount in lead-free secondary solder Sn99. Lead-free soldering is an emerging area in the metallurgy of non-ferrous metals with a non-harmful effect on the environment. This method of soldering is very important for connecting materials in precision electrical engineering. In the experimental part of the paper are evaluated properties of lead-free solder Sn99 with graduated amount of Ge, compared with lead-free solder with the addition of nickel and silver. The goal was to provide knowledge on the impact of germanium on microstructure change, solderability and formation of oxides on the surface. From the results it can be concluded that germanium in lead-free solders reduces the formation of oxides on the surface by the addition of 0.01 wt. % Ge to the batch. With the amount of 0.01 wt. % also the grain is refined in the microstructure, resulting in improved castability. In terms of solderability experiments confirmed that germanium improves the flowability of solder on the PCB substrate.

The effect of microstructural banding (or so called segregation bands) on energy absorption capacity of dual-phase steels (DP steels) was examined by product of tensile strength and uniform elongation (TS×UE), as well as by Charpy V-notch impact test. A series of DP steels with different volume fractions of martensite (VFM) was prepared by intercritical annealing at temperatures ranging 740 to 840 °C. It was found that increasing of VFM has an inverse effect on values TS×UE and notch toughness. The results on samples with a notch and pre-cycled crack showed that presence of segregation bands influences capacity of steels to absorb the energy in initial stage as well as in stage of crack propagation.