Manufacturing Technology Journal, 2019 (vol. 19), issue 5
The SEM Metallography Analysis of Vacuum Cast ZhS6K Superalloy Turbine Blade after Various Working Hours
Juraj Belan, Alan Vaško, Lenka Kuchariková, Eva Tillová, Mária Chalupová
Manufacturing Technology 2019, 19(5):727-733 | DOI: 10.21062/ujep/362.2019/a/1213-2489/MT/19/5/727 
A vacuum cast Ni-base superalloy ZhS6K is used for the production of turbine blades whose are working in the hot section of turbine in former USSR DV-2 jet engine. The usual working temperature for this kind of alloy is designed for 800/1050°C. Turbine blades with protective alitized layer made from this alloy were evaluated at the starting stage, then after 600, 1000, 1500 and 2000 hours of regular working. The SEM methods of quantitative metallography were used for structural characteristics evaluation. The microstructural analysis shows increasing of the medium distance of secondary dendrite arms D, what is related to chemical changes in dendritic...
Analysis of the Impact of the Change of Primary and Secondary AlSi9Cu3 Alloy Ratio in the Batch on its Performance
Dana Bolibruchová, Marek Matejka, Michal Kuriš
Manufacturing Technology 2019, 19(5):734-739 | DOI: 10.21062/ujep/363.2019/a/1213-2489/MT/19/5/734
The ratio of primary and secondary alloy in the batch is important in determining and evaluating the quality of the alloy. The resulting quality of the casting and the costs associated with its production are directly related to the composition of the raw materials entering the smelting process. With the use of an alloy composed of a high proportion of recycled material a negative effect on performance can be expected despite its economic benefits. Based on the results of thermal analysis, mechanical properties and microstructure analysis, the effect of changing the primary and secondary AlSi9Cu3 alloy ratio in the batch was determined. A negative...
Magnesium Composite Materials Prepared by Extrusion of Chemically Treated Powders
Drahomír Dvorský, Jiří Kubásek, Dalibor Vojtěch
Manufacturing Technology 2019, 19(5):740-744 | DOI: 10.21062/ujep/364.2019/a/1213-2489/MT/19/5/740
This paper is focused on the preparation of the magnesium composite materials by extrusion of the chemically treated powders. Microstructures with partially preserved borders between particles containing specific elements depending on the preparation method were created by extrusion. Compressive mechanical properties of extruded chemically treated powders were similar to material prepared from atomized powder. The corrosion rate was reduced by three times in the case of chemically treated powder compared to the pure Mg. Ignition temperature of the chemically treated powder increased by up to 200 °C compared to the atomized powder, while ignition temperatures...
Effect of Nitriding on the Microstructure and Mechanical Properties of Stainless Steels
Petr Faltejsek, Zdeněk Joska, Zdeněk Pokorný, David Dobrocký, Zbyněk Studený
Manufacturing Technology 2019, 19(5):745-748 | DOI: 10.21062/ujep/365.2019/a/1213-2489/MT/19/5/745
Austenitic stainless steels are common spread in many industries. Plasma nitriding is one of the few technologies that allows surface modification of austenitic stainless steels. In this study, a plasma nitriding method to form a hard surface layer at two different austenitic steels AISI 302 and AISI 316L. The surface morphology, chemical composition and mechanical properties of the formed layers were described and the results were compared with each other. The formed nitrided layers on both steels created a uniform multi-phase layer which was characterized by high hardness and very good abrasion resistance.
Analysis of the Cause of Titanium Endoprosthesis Failure
Patrícia Hanusová, Peter Palček, Milan Uhríčik
Manufacturing Technology 2019, 19(5):749-752 | DOI: 10.21062/ujep/366.2019/a/1213-2489/MT/19/5/749
This paper deals with the causes of failure of total hip replacement. Hip joint replacement is one of the most frequently used surgical procedures worldwide. More than 200,000 surgeries are performed only in Europe each year, following early attempts by John Charnley. Currently, more than 340 of the total 4431 implants per year are reoperated in Slovakia. Despite the excellent properties of the titanium alloy, endoprosthesis often fails and the hip replacement is necessary. Common causes are overloading and cracking, static or dynamic. Other causes of failure include injury, implantation failure, manufacturing inaccuracies, and non-compliance with...
Finite Element Analysis of a Lightweight Milling Cutter for Metal Additive Manufacturing
Pavel Hanzl, Miroslav Zetek, Vojtěch Rulc, Hynek Purš, Ivana Zetková
Manufacturing Technology 2019, 19(5):753-758 | DOI: 10.21062/ujep/367.2019/a/1213-2489/MT/19/5/753
Previous work has proposed a process for implementing a lattice structure into a milling cutter body based on clustering in the milling cutter with modified main dimensions of a BCC cubic lattice structure cell. A finite element analysis model has been created to predict the strain and deformation in the struts of the lattice. The prediction made according to static loads demonstrates that the concept of a lightweight cutter meets the strength requirements, though its stiffness does not reach the fully-filled version. The methodologies for creating the FE model are described in this paper. HyperWorks with OptiStruct were used for these analyses. Local...
Enhancement the Corrosion Resistance of AISI 304 Stainless Steel by Nanocomposite Gelatin-Titanium Dioxide Coatings
Mohammed T. Hayajneh, Mohammed Almomani, Mohammad Al-Daraghmeh
Manufacturing Technology 2019, 19(5):759-766 | DOI: 10.21062/ujep/368.2019/a/1213-2489/MT/19/5/759
AISI 304 stainless steel is widely used in many industries due to its good properties such as corrosion resistance and mechanical properties. However, this steel is usually exposed to a severe environment that leads to high corrosion and mechanical failure. This study aims to examine the corrosion behavior of spin-coated AISI 304 stainless steel in a simulated marine environment contains 3.5 wt. % NaCl, by preparing and characterizing nanocomposite coatings with different weight fractions of TiO 2 (0, 1, 2, 3 wt. %) dispersed in a gelatin matrix. Three spinning speed sets (Low (L): 250-1000, Medium (M): 500-2500 and High (H): 750-4000) rpm were chosen...
Analysis of Microstructure Changes for AlSi7Mg0.3 Alloy Caused by Modification
Iryna Hren, Jaroslava Svobodova, Štefan Michna
Manufacturing Technology 2019, 19(5):767-771 | DOI: 10.21062/ujep/369.2019/a/1213-2489/MT/19/5/767
The aim of this experiment was to investigate the influence of the Sr modifier in the Al-Si eutectic alloy on the structure change and its mechanical properties. For this reason, an Al-Si7Mg0.3 hypoeutectic silumin alloy was modified with the aim of improving the mechanical properties of the material, mainly by increasing the ductility and strength. The subject of investigation was analysis of morphology of excreted eutectic silicon. In order to investigate the surface, metallographic cross-sectional specimens were prepared using light and electron microscopy. A static tensile test was performed for detailed examination. It has been found that the...
Analysis of the Effect of Trochoidal Milling on the Surface Roughness of Aluminium Alloys after Milling
Jerzy Józwik
Manufacturing Technology 2019, 19(5):772-779 | DOI: 10.21062/ujep/370.2019/a/1213-2489/MT/19/5/772
The paper presents the results of the surface morphology of aluminium alloys after milling. The 3D surface roughness parameters Ra, Rz, RSm were examined. Functional relationships between the cutting forces, the torque and the roughness parameters were established. The investigation was carried out with respect to functional characteristics of the surface of aluminium alloys. Two different aluminium alloys: 2024 and 6082, were investigated. Two different milling strategies were employed: milling with a trochoidal tool path and milling with a conventional tool path. Different radial depths of cut were applied in the tests. The percentage of the radial...
Colour Treatment of Aluminium Roof Sheets, a Significant Operating Factor
Pavel Kic, Miroslav Müller
Manufacturing Technology 2019, 19(5):780-785 | DOI: 10.21062/ujep/371.2019/a/1213-2489/MT/19/5/780
Aluminium roofing is used for low weight, good strength and weather resistance, easy handling and assembly, for various roofs of industrial and agricultural buildings, residential and family houses, holiday homes, garages and various shelters. Important is very long life, relatively low price and the possibility to choose the colour design according to your taste. The basic form is a natural unpainted finish, which can be used because the aluminium roofing material is not subject to corrosion and is chemically stable. The aim of this research is to verify a suitable method of measuring the colour of aluminium roofing and to determine the basic characteristic...
Influence of Preformed Adherent Angle and Reinforcing Glass Fibre on tensile strength of Hybrid Adhesive Bond
Viktor Kolář, Miroslav Müller, Martin Tichý, Anna Rudawska, Monika Hromasová
Manufacturing Technology 2019, 19(5):786-791 | DOI: 10.21062/ujep/372.2019/a/1213-2489/MT/19/5/786
Adhesive bonding technology present a perspective method of various materials bonding and replacing conventional bonding e.g. welding. A geometric shape modification of bonding material and an adhesive reinforcing by glass fibres to increase tensile strength of adhesive bond was subject of this research. The bonding material was modified into preformed angles 5°, 10°, 15°, 20° and adhesive bond with 0° was se t as the etalon. The adhesive was modified by glass fibre with weight 80, 110 and 160 g.m-2. The research proved tensile strength increase from 4 to 48% by various preformed adherent angles. The research also proved tensile strength increase from...
Comparison of Damping Effects of Two Types of Graphite Cast Iron
Petra Kováčiková, Andrej Dubec, Ján Vavro
Manufacturing Technology 2019, 19(5):792-796 | DOI: 10.21062/ujep/373.2019/a/1213-2489/MT/19/5/792
This paper deals with the evaluation of the graphite cast iron structure and change of the dynamic behavior dependent on the graphite shape. Structural analysis is focused on the study of cast iron with flake and globular graphite. These two materials have a considerable application in manufacturing due to its specific mechanical and physical properties. The production of gray cast iron is less demanding in terms of the technological process and the quality of the raw materials compared to ductile cast iron but this material is the best for the production of castings. Compared with cast steels are these graphite castings less susceptible to the notch...
Effect of Wall Thickness on the Quality of Casts from Secondary Aluminium Alloy
Lenka Kuchariková, Eva Tillová, Richard Pastirčák, Milan Uhríčik, Denisa Medvecká
Manufacturing Technology 2019, 19(5):797-801 | DOI: 10.21062/ujep/374.2019/a/1213-2489/MT/19/5/797
This paper will investigate the changes in size and amount of the microstructural features in secondary aluminium casts associated with different wall thickness. The experimental samples were casting into the sand mould. The changes were documented and assessment by using optical microscope and methods of quantitative analysis. The results shows that increasing wall thicknes lead to formation larger second phases and coarsening of the matrix, which lead to decreasing mechanical properties.
Influence of AlSi7Mg0.3 Alloy Modification on Corrosion Behaviour in the Salt Environment
Sylvia Kusmierczak, Iryna Hren
Manufacturing Technology 2019, 19(5):802-806 | DOI: 10.21062/ujep/375.2019/a/1213-2489/MT/19/5/802
In the case of eutectic and hypoeutectic silumins, the modification is carried out on molten metal prior to casting with strontium, which has a limited modification effect of max. 1 - 1.5 hours. The aim of the realized experiment is to investigate the microstructure change and corrosion evaluation of the AlSi7Mg0.3 aluminium alloy in combination with the strontium modifier. AlSi7Mg0.3 alloy was used for the experiment using 0.04% strontium modifier and 0.15% beryllium was added to prolong the time effect of the strontium modification. Beryllium was used as an AlBe5 master alloy and the samples were cast by gravity casting into a metal preheated mold....
Effect of Sr, Ti and B Additions as Powder and a Preliminary Alloy with Al on Microstructure and Tensile Strength AlSi9Mg Alloy
Tomasz Lipiński
Manufacturing Technology 2019, 19(5):807-812 | DOI: 10.21062/ujep/376.2019/a/1213-2489/MT/19/5/807
The initial structure of AlSi9Mg alloy is com posed of granular and acicular β phase, with α phase as matrix. The hard, irregular, often pointed β phase is responsible for the poor mechanical properties of said alloy. This composition is responsible for the alloy's low strength parameters, and it limits the extent of practical applications. This study presents the results of modification of an AlSi9Mg alloy with strontium, boron and titanium in different ranges produced as a melted modifier added as powders and as rod. The influence of the analyzed additions on the microstructure and tensile strength of the silumin was presented in...
Influence of Cooling Speed during Melt Spinning Process on Properties of Al-Fe-Mm-Si-Mg Bulk Materials Prepared by SPS
Alena Michalcová, Jan Zábrodský, Anna Knaislová, Zdeněk Kačenka, Ivo Marek
Manufacturing Technology 2019, 19(5):813-816 | DOI: 10.21062/ujep/377.2019/a/1213-2489/MT/19/5/813
This work is devoted to description of microstructure of bulk Al-Fe-Mm-Si-Mg alloys and their thermal stability. The alloy was prepared at different cooling rates (600, 1000 and 1400 RPM) during melt spinning process and sintered at the same conditions by SPS. The aim of this work was to prove if change in melt spinning conditions influence the behaviour of bulk material. It was proven that independently on cooling rate precipitation occurs during sintering process. All materials exhibited heterogenous microstructure composed of fine and coarse areas - residue of melt spinning process. During annealing of bulk materials prepared by powder metallurgy,...
Production of Porous Aluminium Using Sodium Chloride
Iva Nová, Karel Fraňa, Jiří Sobotka, Pavel Solfronk, David Koreček, Iva Nováková
Manufacturing Technology 2019, 19(5):817-822 | DOI: 10.21062/ujep/378.2019/a/1213-2489/MT/19/5/817
Our workplace, Technical University of Liberec, is currently engaged in research and production of cellular metal systems. Basically, cellular metal systems are materials with lower density. It is a research in the field of mechanical engineering that is focused on the development of new materials. In general, many methods have been developed for the production of cellular metal systems, e.g. by BANHART [2] or ASHBY [4]. At their production, the direct gassing of molten metals (mostly aluminium ones) or gassing by the powder agents (e.g. specially formulated aluminium powders) are mostly used. Depending on the manufacturing method, a cellular system...
Influence of the Welding Process on the Change of Mechanical Properties in the HAZ of Welds at Alloy AW 6005 and Possibilities of Their Renewal by Heat Treatment
Iva Novakova, Jaromir Moravec, Martin Svec, Tomas Kik, David Korecek
Manufacturing Technology 2019, 19(5):823-830 | DOI: 10.21062/ujep/379.2019/a/1213-2489/MT/19/5/823
This paper deals with monitoring the influence of welding on the mechanical properties degradation in HAZ of welds at aluminium alloy AW 6005 and also with assessing the possibility of utilization the heat treatment to minimize these effects. Workpieces from alloy AW 6005 are mostly supplied in aged state. After application of the temperature cycles during welding, there is a very intensive decrease of the mechanical properties in HAZ. The mechanical properties of the weld metal, HAZ and parent material were evaluated by means of the Vickers hardness. Moreover, influence of annealing and artificial aging on the final mechanical properties of the parent...
Observation of Phase Transformations in High-temperature Chamber under Microscope Objective Lens
Michal Peković, Kateřina Opatová, Kateřina Rubešová, Tomáš Janda, Hana Jirková, Radovan Bureš
Manufacturing Technology 2019, 19(5):831-835 | DOI: 10.21062/ujep/380.2019/a/1213-2489/MT/19/5/831
Today, extensive information on a particular material can be obtained from its chemical composition using various computer programs. Such information includes phase transformation temperatures, such as Ac1 and Ac3 or the Ms and Mf, as well as the entire austenite decomposition sequence, as shown in TTT and CCT diagrams. When steel is heated, austenite grains begin to form, grow and eventually coarsen. On cooling, these grains decompose into pearlite, ferrite, cementite and hardening phases. Transformations of this kind are well understood nowadays, namely the ways the individual phases form and the rates and temperatures involved. Yet, in-situ visual...
Influence of Processing on the Microstructure and the Mechanical Properties of Zn/HA8 wt.% Biodegradable Composite
Jan Pinc, Eva Miklášová, Filip Průša, Jaroslav Čapek, Jan Drahokoupil, Dalibor Vojtěch
Manufacturing Technology 2019, 19(5):836-841 | DOI: 10.21062/ujep/381.2019/a/1213-2489/MT/19/5/836
Zinc-based materials show large potential to become biodegradable materials with ideal corrosion behavior in the body environment. In this study, a zinc composite containing 8 wt. % of hydroxyapatite (HA) was prepared by spark plasma sintering (SPS) and characterized from a point of view of the microstructural and mechanical properties. The influence of pre-processing (milling) of the powders on the microstructure after the sintering was studied. The materials prepared by the milling and subsequent sintering showed insufficient cohesion due to the wrapping of Zn by HA particles and possible oxidation of zinc particles. Compressive and flexural tests...
Strength Computation of Bearing Test Station
Milan Sapieta, Martin Svoboda
Manufacturing Technology 2019, 19(5):842-847 | DOI: 10.21062/ujep/382.2019/a/1213-2489/MT/19/5/842
The test station is used to determine the fatigue of bearings in passenger cars. The influence of prestressing or axial clerance, the reliability of the locking elements for the axial adjustment, the quality of the seating of the outer ring and the change in the type, quantity or distribution of the lubricant can also be examined. The test station consists of a test unit for the simultaneous testing of two test bearings. The misalignment of the wheel contact point and the center of the bearing is fixed by means of mountable parts. The test bearings are clamped between the flanges at both ends of the test shaft, which is supported by two auxiliary bearings....
Cooling Aluminium Coils by Outdoor Air
Dieter Sedlacek, Berenika Hausnerova
Manufacturing Technology 2019, 19(5):848-854 | DOI: 10.21062/ujep/383.2019/a/1213-2489/MT/19/5/848
Aluminium extraction and production is energy intensive and have a relatively large environmental impact. One of the steps in the production of sheet aluminium is the cooling of the rolled metal after the hot mill. This study introduces an option to replace the active cooling by an environmental friendly method and eliminate the otherwise necessary logistic step of relocating the coils after cooling. This was done by developing a thermal model of the coils, calculating, based on the model, the required airflow and verifying it with test series. The experimental setup is in a high-bay storage facility belonging to a aluminium production line. The results...
The Implementations of Suitable Cutting Parameters by Grinding of Titanium VT9 with Impact on Surface Integrity
Dana Stancekova, Anna Rudawska, Miroslav Neslušan, Jozef Mrázik, Miroslav Janota
Manufacturing Technology 2019, 19(5):855-859 | DOI: 10.21062/ujep/384.2019/a/1213-2489/MT/19/5/855
Despite the fact that Titanium alloys are frequently used in medicine, aviation industry and also in machine manufacture due to their strength and resistance against external influences. Moreover, their innovation to obtain better and more suitable parameters still proceeds. Regarding their mechanical properties, they are considerably less machinable which affects surface integrity of a machined area. That is why a proper selection of a machine tool and cutting conditions are extremely important. This paper deals with a finishing grinding process of the material VT9 by means of specific grinding wheels 5TG and DIA under specified cutting conditions....
Identification of Changes in Mechanical Properties of Human Axial System Due to Stress and Relaxation Regime
Martin Svoboda, Kateřina Van der Kamp, Karel Jelen, Milan Sapieta
Manufacturing Technology 2019, 19(5):860-867 | DOI: 10.21062/ujep/385.2019/a/1213-2489/MT/19/5/860
The aim of this work was to verify the applicability of the TVS (Transfer Vibration through Spine) methodology for registration of changes in viscoelastic characteristics of the axial system. The detection method consists in applying γ pulse pulses with a half-width of 5ms and then a harmonic excitation of continuously varying from 5Hz to 160Hz on vertebrae C7 and L5. This ripple is transmitted along the axial system and acceleration of all the spinous processes of the vertebrae is sensed by accelerometer sensors to propagate the wave between C7 and S1. On the basis of measured data (input excitation and its sensed response on spinous processes),...
Identification of the "Snowflakes" on the Machined Surface of the AlSi10Mg Alloy Casting
Jaroslava Svobodová, Milan Luňák, Ivan Lukáč
Manufacturing Technology 2019, 19(5):868-873 | DOI: 10.21062/ujep/386.2019/a/1213-2489/MT/19/5/868
The usage of aluminium alloys has an increasing trend in the manufacturing industry in recent years. This fact is connected with their ability to combine their very good properties. Characteristics of aluminium are low specific weight, very good thermal and electrical conductivity, and ductility. However, the major disadvantages are low strength and hardness. Therefore the aluminium alloys are alloyed with the elements, which would significantly improve the properties of aluminium. The machining process of aluminium alloys is influenced by many factors that affect the machinability. These factors are for example process conditions, cutting tool material,...
Sludge Phases as Cause of Higher Wear of Cutting Tools during Machining of Secondary AlSi12Cu1 Castings
Eva Tillová, Mária Chalupová, Lenka Kuchariková, Ivana Švecová, Juraj Belan
Manufacturing Technology 2019, 19(5):874-879 | DOI: 10.21062/ujep/387.2019/a/1213-2489/MT/19/5/874
Present work is focused to determine the cause of higher wear of castings made of secondary (recycled) AlSi12Cu1 cast alloy after switching supplier and the morphological evolution of Fe-rich phases has been documented. As recycling of Al-alloys becomes more common, sludge will be a problem of increasing importance due to the concentration of Fe, Mn and Cr in the scrap cycle. The tendency of Al-Si-Cu alloys to form sludge Fe-rich particles can be predicted by the sludge factor (SF) equation, which represents an attempt to gather the combined effects of Fe, Mn and Cr. Sludge phases are hard and brittle phases which can compromise the machining operations,...
Integrated Tool for High-Feed Turning
Karol Vasilko
Manufacturing Technology 2019, 19(5):880-885 | DOI: 10.21062/ujep/388.2019/a/1213-2489/MT/19/5/880
Machining, mainly turning, si characterised by the highest labour input among the technological methods. This leads to the conditin when, for instance, in line production at hammering power press, which produces forginngs in the stroke of 1 second, tens of lathes follow and their gradual turning with the stroke of tens of seconds up to minutes. Whole history of material machining has been lead with the effort to shorten machining time by the improvement of cutting materials, tool geometry, integration of machining The article based on the method integrates roughing and finishing into one operation and ensures high quality of machined workpiece surface.
Accuracy of Portable Hardness Testers
Alan Vaško, Ján Sovík, Zuzana Sedliačková
Manufacturing Technology 2019, 19(5):886-890 | DOI: 10.21062/ujep/389.2019/a/1213-2489/MT/19/5/886
Hardness tests enable to determine one of the main mechanical properties of the material, namely hardness. For hardness testing, it is possible to use either conventional desk hardness testers or the currently increasingly used portable hardness testers. The paper is focused on determination of the accuracy and reliability of static (desk) and dynamic (portable) hardness testers. The paper deals with the measurement of hardness of calibration hardness plates by 4 different methods (Brinell, Vickers, Rockwell and Leeb) with using 5 different hardness testers (3 desk and 2 portable). The hardness values measured by the different hardness testers were...
Experimental and Numerical Modal Analysis of the Carbon Composite Plate Damaged by Cut
Ján Vavro jr., Ján Vavro, Alena Vavrová
Manufacturing Technology 2019, 19(5):891-895 | DOI: 10.21062/ujep/390.2019/a/1213-2489/MT/19/5/891
The given paper is closely connected with the experimental and numerical modal analysis of the carbon composite plate damaged by cut. In relation to the tested carbon composite, modal analysis was performed by help of special measuring device Pulse 12. The mentioned device was supplied by company Brüel & Kjear and the experimental measurements were carried out using damaged and undamaged plate sample which were prepared from the mentioned material hereinbefore. The investigated and analyzed plates of carbon composite were made of six layers of carbon fibres and they were arranged under the angle 90º (it is like fabric material made off carbon...
Induction Brazing Analysis of EAST Fast Control Coil Conductor
Xianewei Wang, Peng Han, Qing He, Xiulian Li, Huan Jin, Chengtao Yu
Manufacturing Technology 2019, 19(5):896-902 | DOI: 10.21062/ujep/391.2019/a/1213-2489/MT/19/5/896
To achieve much higher operation parameters of EAST device, some key components are upgraded. Fast control coil as one of the key components is updated by using novel stainless steel mineral insulation conductor and the turns are increased to 4, which means the coil's operation environment becomes more severe and larger loads will be encountered. The coil joint is apt to be destroyed in view of the potential defects during the fabrication. Given the numerous advantages, the induction brazing is being considered for the conductor joint connection. The copper mock up is used to carry out the feasibility analysis. Based on the structural size of copper...