Manufacturing Technology Journal, 2018 (vol. 18), issue 4
Monitoring Changes in the Tribological Behaviour of CrCN Thin Layers with Different CH4/N2 Gas Ratios at Room and Elevated Temperatures
Totka Bakalova, Nikolay Petkov, Hristo Bahchedzhiev, Pavel Kejzlar, Lukáš Voleský
Manufacturing Technology 2018, 18(4):533-537 | DOI: 10.21062/ujep/133.2018/a/1213-2489/MT/18/4/533 
This research is engaged in monitoring changes in the tribological behaviour of CrCN thin films at room and elevated (300°C) temperatures. The monitored thin films are deposited by cathodic arc deposition of a pure Cr (99.99 %) cathode under an atmosphere of a mixture of CH4 and N2 gasses. Tribological measurements were performed at a load of 10N, a rotational speed of 60 rpm, and a counterpart of ceramic material (Al2O3). The article also describes the evaluation of wear on the studied thin films due to tribological measurement and temperature.
The Influence Surface Treatment on the Firmness of Spot Welds
Milan Brožek
Manufacturing Technology 2018, 18(4):538-544 | DOI: 10.21062/ujep/134.2018/a/1213-2489/MT/18/4/538
. Spot welding is a commonly used technology in practice to join metal material. It applies to all types of production, mass, series and piece production. Its biggest advantage is the high productivity, with which it is possible to weld. As with other welding methods, the cleanliness of the welded surfaces is important. The aim of the tests performed was to evaluate the influence surface treatment on the firmness of the test specimens of spot welds. The test specimens were made from steel. Welding was done while using manual clamp welders. Four sets of metal sheets were prepared before the welding, with different surface treatment - surface without...
Neutron Irradiated Reactor Internals: An Applied Methodology for Specimen Preparation and Post Irradiation Examination by Electron Microscopy Methods
Petra Bublíková, Patricie Halodová, Miroslav Fokt, Hygreeva Kiran Namburi, Vít Rosnecký, Jan Procházka, Jan Duchoň, Dalibor Vojtěch
Manufacturing Technology 2018, 18(4):545-551 | DOI: 10.21062/ujep/135.2018/a/1213-2489/MT/18/4/545
Radiation-induced microstructural defects cause degradation of mechanical properties and a life time reduction of reactor structural components during nuclear power plant operation. The effect of neutron irradiation fluence and flux, neutron spectrum, corrosion environment, etc. on mechanical properties is investigated under the NPP's surveillance programs and additional nuclear material research. The material strength typically increases while ductility and fracture toughness decrease after neutron irradiation. Transmission Electron Microscopy is one of the methods for Post Irradiation Examination (PIE) which helps to understand the material behaviour...
Optimizing Fabrication Outcome in Low-Cost FDM Machines. Part 2 - Tests
Francesco Buonamici, Monica Carfagni, Rocco Furferi, Lapo Governi, Marco Saccardi, Yary Volpe
Manufacturing Technology 2018, 18(4):552-558 | DOI: 10.21062/ujep/136.2018/a/1213-2489/MT/18/4/552
Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focused on the definition of a series of metrics to be measured on a series of test prints to evaluate...
Mechanical Properties of Inconel Alloy 718 Produced by 3D Printing using DMLS
Milan Daňa, Ivana Zetková, Josef Mach
Manufacturing Technology 2018, 18(4):559-562 | DOI: 10.21062/ujep/137.2018/a/1213-2489/MT/18/4/559
Additive manufacturing (AM) allows printing from different materials: from wax to plastic and even metal. This paper concentrates on Direct Metal Laser Sintering (DMLS), which allows printing to create complex parts from different kinds of metal. Inconel 718 was chosen for this research. This material is used especially in the aerospace industry and in other demanding applications due to its characteristic properties, which include high strength at high temperatures, corrosion resistance, low thermal conductivity, high hardness, work hardening and low thermal conductivity. Components used in aeroplanes must be very reliable, lightweight and their mechanical...
Dimensional Accuracy of a Product Built Using Direct Metal Laser Sintering
Pavel Hanzl, Ivana Zetková, Jan Kutlwašer
Manufacturing Technology 2018, 18(4):563-566 | DOI: 10.21062/ujep/138.2018/a/1213-2489/MT/18/4/563
Direct Metal Laser Sintering (DMLS) is a method of Metal Additive Manufacturing which builds metal parts in a layer-by-layer procedure based on a CAD template. This method is diametrically different from machining methods such as turning or milling. Nowadays, DMLS is used for rapid manufacturing of complex metal parts. However, these products do not meet the requirements of high accuracy and surface quality. This paper deals with factors that are involved in the dimensional precision of DMLS production. The purpose of the Scale and Beam offset correction coefficients are described in the paper. Practical experiments and measurements were carried out...
Specifications of Wear of Oils in Two-Fuel Systems
Vladimír Hönig
Manufacturing Technology 2018, 18(4):567-571 | DOI: 10.21062/ujep/139.2018/a/1213-2489/MT/18/4/567
Article focuses on the monitoring of motor wear of vehicles powered by a dual-fuel diesel-vegetable oil system. The introductory part focuses on the use of biofuels for combustion engines and tribotechnical diagnostics for wear testing. Analysis of engine oil samples from vehicles with different fuels is carried out. Fuel is diesel fuel, biodiesel and a two-fuel system with two fuels - rapeseed oil and diesel fuel. The abrasion wear of biodiesel is increased. Wear in dual fuel system is within the standard exchange interval in the zone of emergency wear of metallic particles and carbon. The article evaluates the adjustment of the oil exchange interval...
The Possibility for Improving Damage Tolerance of Integral Airframe Structure by High Strength Bonded Straps
Vaclav Jetela, Josef Klement, Petr Augustin
Manufacturing Technology 2018, 18(4):572-577 | DOI: 10.21062/ujep/140.2018/a/1213-2489/MT/18/4/572
Integral stringer panels can attain weight reduction in primary aircraft structures, but do not contain the physical barriers for a fatigue crack growth. One of the promising techniques for prolonging a fatigue crack growth is bonded crack retarders made of materials with high stiffness. An experimental study was done on two specimens with different geometries. High strength bonded straps made of corrosion resistant steel AISI 301 were adhesively bonded to Center-Cracked Tension (CCT) specimens made of aluminium alloy 2024-T351 and fabricated by a high-speed machining process to promote fatigue crack growth retardation. Specimens were tested at a constant...
Quality Evaluation of the Coatings and Its Influence on the Wood Machining Tool Wear
Daniela Kalincová, Miroslava Ťavodová, Dagmar Jakubéczyová
Manufacturing Technology 2018, 18(4):578-584 | DOI: 10.21062/ujep/141.2018/a/1213-2489/MT/18/4/578
Coating of the tools for metal machining has been used for a long time, application of the coating to wood machining tools is not so explored. The aim of research in this area is to expand the possibilities of the using of PVD coatings in untraditional field at wood wool production in company, that thermo isolation and sound isolation plates manufactures. In the production of wood fibers by technology like planning, during the work the cutting edge of the knife is worn-down and the resulting product loses quality. Often grinding is required, knife dimensions are changed and lose its functional surface. The article is focused on the choose of the coating...
The Study of the Effect of Mechanical and Heat Treatment on the Crystal Texture of Cold Drawn Seamless Tubes
Pavel Kejzlar, Ondřej Seibert, Zuzana Andršová, Peter Burik
Manufacturing Technology 2018, 18(4):585-592 | DOI: 10.21062/ujep/142.2018/a/1213-2489/MT/18/4/585
Seamless tubes are the strongest amongst all tubes types and have a homogeneous structure throughout their length. They are typically manufactured by cold drawing where strong grain deformation takes place. EBSD was used to evaluate the changes of grain structure and texture connected with tubes manufacturing from the initial state over the cold drawing with a stationary plug to subsequent recrystallization annealing.
Microstructure of TiAl15Si15 Alloy Prepared by Powder Metallurgy
Anna Knaislová, Pavel Novák, Filip Průša, Jaromír Kopeček
Manufacturing Technology 2018, 18(4):593-596 | DOI: 10.21062/ujep/143.2018/a/1213-2489/MT/18/4/593
This work deals with the microstructure of TiAl15Si15 intermetallic compound, which can be used as a high-temperature low-weight material especially for the automotive and aerospace industry. A combination of high mechanical properties, good oxidation resistance and low density of this material is a good potential for use this alloy in many applications. The TiAl15Si15 alloy was prepared by different techniques of powder metallurgy. In this work, microstructure after reactive sintering, reactive sintering in a combination of Spark Plasma Sintering and mechanical alloying followed by Spark Plasma Sintering was described. The results were compared with...
Microstructure Evaluation of Ductile Cast Iron and Numerical Modal Analysis
Petra Kováčiková, Ján Vavro, Ján Vavro jr., Andrej Dubec
Manufacturing Technology 2018, 18(4):597-599 | DOI: 10.21062/ujep/144.2018/a/1213-2489/MT/18/4/597
This work is closely connected with the evaluation of the microstructure of the cast iron with the spherical shape of graphite. The given work is mainly focused on mechanical properties, chemical composition and microstructure, which are important to be known as an input parameters for computational modelling and numerical analysis. The external factors, influencing the measure of the mechanical damping, include the measure of the mechanical loading, loading frequency and temperature. These factors have the influence on the process of the mechanical energy distribution in materials. Eigenshapes as well as eifenfreguencies were investigated by modal...
The Potential for Heat Treating Cemented Carbides
Antonín Kříž, David Bricín, Vojtěch Průcha
Manufacturing Technology 2018, 18(4):600-604 | DOI: 10.21062/ujep/145.2018/a/1213-2489/MT/18/4/600
The focus at the outset was on nothing more than cryogenic treatment of cemented carbides. Then, in relation to additional findings arising from heating of cemented carbides, this paper was expanded to include the results of heat treatment and the behaviour at elevated temperatures. Although heat treatment is applied to diverse materials, no profound study of heat treatment has been dedicated to cemented carbides. This is despite the fact that both cryogenic treatment and heating to elevated temperatures have been proven to cause changes in their properties. Not all these changes are favourable. If precisely-defined rules are not followed, the changes...
Effect of Aluminium and Manganese Contents on the Microstructure Development of Forged and Annealed TRIP Steel
Ludmila Kučerová, Hana Jirková, Julie Volkmannová, Jiří Vrtáček
Manufacturing Technology 2018, 18(4):605-610 | DOI: 10.21062/ujep/146.2018/a/1213-2489/MT/18/4/605
Three low carbon steels with 1.5 and 3%Mn and either 1.5%Al or 2%Al were forged from cast ingots into bars using various heating temperatures and deformation conditions. Bars were heat treated by annealing at 950 °C to gain homogenized input materials for subsequent experiments. The effect of various austenitization temperatures and holds in the region of 800 -1200 °C was tested with regard to the final microstructure and hardness development. Hardness in the region of 320-550 HV 10 was obtained. The highest hardness was for all austenitizing temperatures achieved for 1.5Al3Mn steel and it decreased with decreasing manganese to aluminium content ration....
Observation on the Formation of β-Al5FeSi Phase Depending on the Content of Fe in Aluminium Cast Alloy
Lenka Kuchariková, Eva Tillová, Juraj Belan, Mária Chalupová, Ivana Švecová, Roman Čička, Milan Uhríčik
Manufacturing Technology 2018, 18(4):611-615 | DOI: 10.21062/ujep/147.2018/a/1213-2489/MT/18/4/611
This work examines the effect on the formation of second Fe phase group Al-Fe-Si: Al5FeSi in aluminium alloy containing the iron of 0.123 wt. %, 0.454 wt. % and 0.655 wt. %. Studies were focused on the size and content of Al5FeSi changes and their effect on the porosity formation and mechanical properties in AlSi7Mg0.3 cast alloys. One of the key problems of these phases is their harmful morphology effect on to properties (mechanical, fracture, fatigue and so on) of aluminium casts. The increasing usage of recycled metals for production new casts is the main factor which influences content of iron in composition of aluminium cast alloys. The observation...
Analysis of the Base Material and Hard Chrome Plated Layer in an Unloaded State
Martin Marek, Martin Novák, Karel Šramhauser, Jaroslava Svobodová
Manufacturing Technology 2018, 18(4):616-620 | DOI: 10.21062/ujep/148.2018/a/1213-2489/MT/18/4/616
The focus of this paper is the analysis of the chrome plated layer and base material in an unloaded state, which will be machined by grinding. Each input analysis is necessary before the experiment, so my input analysis was concerned with the surface and surface layer, where components of integrity were tracked. This research observed surface roughness and profile, circularity, microhardness, microstructure, pores and cracks. This analysis is very important due to differences in the components of surface integrity before and after machining or unloaded and loaded states. Hard chrome plating is practically always applied to parts which are made from...
The Influence of Rapidly Solidified Ribbons Pre-treatment on Structure of Bulk AlFeMm Alloys Prepared by Powder Metallurgy
Alena Michalcová, Tadeáš Bastl, Anna Knaislová, Ivo Marek
Manufacturing Technology 2018, 18(4):621-624 | DOI: 10.21062/ujep/149.2018/a/1213-2489/MT/18/4/621
Rapidly solidified AlFe7Mm4 ribbons were prepared by melt spinning process. The ribbons were composed from super saturated solid solution of alloying elements in Al matrix, stable intermetallic phases and metastable quasicrystalline phases. Both metastable phases can potentially provide self-healing properties to the material - super saturated solid solituon by precititation and quasicrystals by decomposition to stable phases. Key problem of processing such materials is to preserve the microstructure of rapidly solidified material during its compaction. Spark plasma sintering enables powder solidification in very short time - in range of few minutes....
Dependability Analysis of the Injection Press Using Weibull Distribution
Petra Michálková, Václav Legát, Zdeněk Aleš
Manufacturing Technology 2018, 18(4):625-629 | DOI: 10.21062/ujep/150.2018/a/1213-2489/MT/18/4/625
The aim of this paper is an analysis of dependability of an injection press. Collected data - operating times between failures and times to restoration for a year of the use of the press were processed using the Weibull distribution, for which the following basic steps were applied in compliance with ČSN EN 61649:2009 standard. The output includes Weibull distribution parameters and basic functions of reliability and maintainability, i.e. probability of failure and of reliability, density and intensity of failures, then also probability of restoration and restoration probability density. Last but not least, mean time between failures and mean time...
Research on Application of Technology Using Water Jet on Machining of Polymeric Composite Biological-Reinforced Materials
Miroslav Müller, Petr Valášek, Viktor Kolář
Manufacturing Technology 2018, 18(4):630-634 | DOI: 10.21062/ujep/151.2018/a/1213-2489/MT/18/4/630
The paper deals with a machining of polymeric composite materials reinforced with fibres from hemp, false banana (Ensete ventricosum) and microparticles from Jatropha Curcas L. seedcakes by means of a technology using a water jet (abrasive water jet AWJ, water jet WJ). A matrix of the composite material is from a structural resin used for a production of sport equipment which shows good mechanical properties, but is it very brittle and it comes to its destruction during machining. Therefore, the water jet technology was used for the research. The research was focused on the evaluation of an influence of a velocity of a cutting head movement on a kerf...
Using of the Electron Microscope to Evaluate the Tool Wear for a Selected Cutting Insert
Nataša Náprstková, Karel Šramhauser, Jaromír Cais, Dana Stančeková
Manufacturing Technology 2018, 18(4):635-640 | DOI: 10.21062/ujep/152.2018/a/1213-2489/MT/18/4/635
Using of cutting inserts is currently a normal part of the manufacturing process. The article deals with analysis of tool wear after machining at one selected cutting insert. Evaluation of this insert was made by electron microscopy. There was used SEM and EDS analysis. For this purpose was used scanning electron microscope Tescan Vega 3 and EDS analyzer Bruker 16 which is part of this microscope. These analysis can provide a good picture of the structure and construction of inserts, their composition and for situation on the insert after machining. This may assist in finding suitable cutting conditions. As experimental material the hardened steel...
Some Aspects of Surface Integrity after Hard Milling
Miroslav Neslušan, Mária Čilliková, Juraj Uríček, Anna Mičietová, Jiří Čapek
Manufacturing Technology 2018, 18(4):641-644 | DOI: 10.21062/ujep/153.2018/a/1213-2489/MT/18/4/641
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....
Alloying of Fe-Al-Si Alloys by Nickel and Titanium
Kateřina Nová, Pavel Novák, Adrian Arzel, Filip Průša
Manufacturing Technology 2018, 18(4):645-649 | DOI: 10.21062/ujep/154.2018/a/1213-2489/MT/18/4/645
This paper focuses on one part of the otherwise very complex research of intermetallic compounds based on Fe-Al-Si at the UCT Prague. These materials seem to be suitable candidates for use in extreme conditions (high temperatures, oxidation and sulfidation environment, ...), especially in the aerospace and automotive industries. The aim of this work was to describe the influence of alloying elements - Ni and Ti on phase composition, microstructure, mechanical and oxidative properties, in two specific systems - FeAl35Si5 and FeAl20Si20 (in weight %).
The Role of Manganese in the Alloy Based on Al-Si-Mg with Higher Iron Content
Radka Podprocká, Dana Bolibruchová
Manufacturing Technology 2018, 18(4):650-654 | DOI: 10.21062/ujep/155.2018/a/1213-2489/MT/18/4/650
The iron causes the formation of intermetallic phases in Al-Si alloy. These phases are most often present in the form of Al5FeSi phase platelets and degrade alloys properties, especially mechanical. By applying additive elements - correctors (e.g. Mn, Cr, V) we can achieve the change of intermetallic phases morphology to more suitable form. Presented article deals with the influence of manganese as iron corrector on AlSi7Mg0.3 alloy microstructure and length of Al5FeSi phase. The increasing the manganese content reduces the length of Al5FeSi phase, but with higher contents, mainly the skeletal formations was observed instead of the Al5FeSi phase. The...
Properties of Ni-Ti-(Fe,Co,Al) Shape Memory Alloys Prepared by Self-Propagating High-Temperature Synthesis
Pavel Salvetr, Andrea Školáková, Barbora Kašparová, Pavel Novák
Manufacturing Technology 2018, 18(4):655-658 | DOI: 10.21062/ujep/156.2018/a/1213-2489/MT/18/4/655
Shape memory, superelasticity and pseudoplasticity are the exceptional properties of Ni-Ti alloys, which are listed among SMAs (Shape Memory Alloys). The carrier of these properties is the intermetallic NiTi phase. In addition to this phase, the Ti2Ni phase is always present, which is hard and brittle, and therefore it is undesirable in the Ni-Ti alloys. The aim of this work was to determine the influence of selected alloying elements (iron, cobalt and aluminium) in two different amounts (1 wt. % and 3 wt. %) on the microstructure, phase composition and amount of the Ti2Ni phase, hardness and transformation temperature of Ni-Ti-X alloy. The samples...
Analysis of the Power Load when Finishing Very Precise Holes by Reaming Head MT3
Josef Sedlak, Ales Jaros, Martin Slany, Karel Kouril, Jozef Majerik, Igor Barenyi
Manufacturing Technology 2018, 18(4):659-666 | DOI: 10.21062/ujep/157.2018/a/1213-2489/MT/18/4/659
Design and technological development of cutting tools represents a fluent process that combines new knowledge from all usable technical branches with actual needs and development results of component base, production technology and machine tools. The main factors which nowadays accelerate the development of cutting tools are constantly increasing demands to improve efficiency and productivity while reducing operation costs, the application of hard machinable materials, environmental protection issues, health and growing demands for greater safety. The article deals with methodology of measurement and evaluation of cutting forces and cutting torque...
Microstructure and Properties of the First-Republic Czechoslovak Circulation Coins
Jan Šerák
Manufacturing Technology 2018, 18(4):667-673 | DOI: 10.21062/ujep/158.2018/a/1213-2489/MT/18/4/667
In this work, the microstructure and properties of the first-Republic Czechoslovak circulation coins were studied. The variety of the coins at that time was shown. Significant differences in microstructure in the direction of forming and in the normal direction to the surface direction have been confirmed. For some coins, visible features of recrystallization were shown, which suggests the coinage at higher temperatures. The chemical composition of coin alloys was also studied. In most cases, it was consistent with the declared chemical composition by mint. Significant differences in the hardness of the coins were found, which confirmed the different...
Influence of Cutting Parameters on Cylindricity Deviation by Centerless Grinding
Dana Stancekova, Pavol Martikan, Jaroslava Svobodova, Miroslav Janota, Jiri Kratochvil
Manufacturing Technology 2018, 18(4):674-678 | DOI: 10.21062/ujep/159.2018/a/1213-2489/MT/18/4/674
Grinding is one of the oldest ways of material machining operations. The requirement to produce fast and cost-effective parts in large quantities has classified the metal grinding in the engineering industry for major machining operation. The complexity of the abrasive process and the amount of abrasive tool parameters have considerable problems in the theoretical and experimental study of this process, which is machining with undefined cutting-edge tool. The submitted verifications are aimed at intensifying grinding without medium stress due to the cylindrical deviation. Also, these verifications are aimed to the adjustment of centreless grinding...
Analysis of Machinability of New AlSi7Mg0.3 Alloys with Different Calcium Content
Elena Střihavková
Manufacturing Technology 2018, 18(4):679-685 | DOI: 10.21062/ujep/160.2018/a/1213-2489/MT/18/4/679
The field of application of aluminium alloys is very wide and the future use of aluminium alloys is related to the further development of new alloys. Recently, the use of alloys in aluminium alloys is a trend in achieving changes in chemical, mechanical and technological properties. This paper deals with the investigation of the area of calcium influence, especially on the machinability of the alloy. The analysis was performed by alloying AlSi7Mg0.3 with master alloy AlCa10. Four types of samples with different calcium content, from at least 0.1% Ca, up to 1% Ca maximum, were produced. In the case of such samples, research was carried out on the technological...
Material Usage of Oil-Palm Empty Fruit Bunch (EFB) in Polymer Composite Systems
Petr Valášek, Himsar Ambarita
Manufacturing Technology 2018, 18(4):686-691 | DOI: 10.21062/ujep/161.2018/a/1213-2489/MT/18/4/686
This paper describes the material use of EFB biomass in the form of composite systems. It describes the tensile characteristics, hardness and wear resistance of polymeric disordered composites epoxy/EFB prepared by vacuum infusion. Electron microscopy was used to describe cellulose EFB fibers and their microstructures. The paper deals with a very simple material when the fibers were not separated from the EFB biomass - EFB biomass was used as it is produced by the processing line. The experiment describes composites with untreated EFB biomass and EFB biomass treated chemically with alkali - 6% aqueous NaOH. Due to the residue of the seed shells and...
Tribological Mechanism in Machining and Its Use
Karol Vasilko
Manufacturing Technology 2018, 18(4):692-696 | DOI: 10.21062/ujep/162.2018/a/1213-2489/MT/18/4/692
It is a well-known fact that during cutting there occurs an extremely high degree of chip plastic deformation [1,4,5,11] These deformation structures require attention as they influence technical and economical results of cutting (cutting forces, quality of machined surface, tool wear, cutting temperature) [8,9,15,21]. The paper analyses the options of influencing the deformation field in chip with the aim to improve cutting proces.