QUALITY OF 3D PRINTED SURFACE BASED ON SELECTED POST PROCESSOR

MM (Modern Machinery) Science Journal, June_2018
DOI : 10.17973/MMSJ.2018_06_201745
JOZEF TOROK, MAREK KOCISKO, MONIKA TELISKOVA, JAROSLAV PETRUS, DUSAN PAULISIN
Technical University of Kosice, Faculty of Manufacturing Technologies, Department of Computer Aided of manufacturing technologies, Presov, Slovak Republic
e-mail : marek.kocisko@tuke.sk
Abstract
Thanks to the open source project RepRap the 3D printing technology has been delivered from laboratories to normal households. Since the beginning of the project, 3D printing has been constantly gaining in popularity thanks to the relatively simplicity in the production or transformation of ideas into physical models. In addition to the choice of hardware for open-source 3D printer an important factor determining the quality of the finished product is the right choice and settings of the post-processor.
Keywords: Cura Engine, Skeinforge, Slic3r, comparison
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THE INFLUENCE OF THE NETWORK DENSITY ON THE CREEP MODULUS OF RADIATION CROSSLINKED MATERIALS

MM (Modern Machinery) Science Journal, June_2018
DOI : 10.17973/MMSJ.2018_06_201755
MARTIN REZNICEK, MICHAL STANEK, LENKA HYLOVA, DAVID MANAS
Tomas Bata University in Zlin, Zln, Czech Republic

e-mail : mreznicek@ft.utb.cz
Abstract
This article deals with the creep modulus process comparison of two structurally different materials. These are specific materials HDPE (high density polyethylene) and LDPE (low density polyethylene). These materials were chosen because of their shared monomer from which they were created and differ only in the chain shape. Subsequently these materials were beta radiation crosslinked at six various doses, which changed the inner structure for more complex measurement and the extensive description of the given topic. To obtain data Toledo DMA1 device of the company Metler and earlier data were used for use of knowledge. The results show if the radiation doses efficiency is higher for material with higher or lower density.
Keywords: polyethylene, creep, crosslinked, tensile – creep modulus, modulus, time
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TRIBOLOGICAL PROPERTIES OF AL-ALLOY DESIGNED FOR DRAWING STAMPINGS IN AUTOMOTIVE INDUSTRY

MM (Modern Machinery) Science Journal, June_2018
DOI : 10.17973/MMSJ.2018_06_201757
PAVEL SOLFRONK, JIRI SOBOTKA, DAVID KORECEK, MICHAELA KOLNEROVA
Technical University of Liberec, Faculty of Mechanical Engineering, Liberec, Czech Republic
e-mail : pavel.solfronk@tul.cz
Abstract
Strict legislative requirements for environmental protection and tendency to lower consumption of fossil fuels force the car producers to still find new possibilities in the car-body design. As one of such possibilities there is effort to apply materials with low specific weight. Among these belong also Al-alloys that are affordable, but in comparison to steels also difficult to be technologically processed. In paper is evaluated the influence of new coating type on the tribological properties of alloy EN AW 6016 that is used in the automotive industry for drawing stampings. Tribological properties are evaluated by means of 3D surface color maps, where is shown friction coefficient in dependence on sliding velocity and contact pressure. Own state of surface is observed and documented by images from the optical microscope and magnitudes of surface sheet roughness that are measured in parallel and perpendicular direction regarding the rolling direction.
Keywords: Al-alloys, Tribology, Drawing of Sheets, Car-body, 3D Surface Color Map, Friction Coefficient
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PRODUCTION ENHANCEMENT THROUGH USING A CONTINUOUS SYSTEM OF WINDING ELECTRIC MACHINES

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201761
LADISLAV FUGLICEK
Technical university of Ostrava, Faculty  of Mechanical Engineering, Department of Mechanical Technology, Ostrava, Czech Republic
e–mail: ladislav.fuglicek@vsb.cz
Abstract
The article is focused on the practical test of stator coil isolation by a continuous winding system. The winding system has two types. Discontinuous winding requires precise manual winding of the material. Discontinuous winding is time consuming. The use of the winding machine is limited by a maximum voltage of 11 kV. With continuous winding, the machine winding is accurate, the winding time is lower and the winding machine is used for a voltage greater than 11 kV. The disadvantage is the greater number of multi-stage corrosion protection strips that are pressed into the coil.
The next part deals with the time sequence in operations and production tests with coils Un = 6 kV and Un = 11 kV.
The result of this study is to make the production of stator coils more efficient by means of a machine winding device and suitable determination of types of stator coils.
Keywords: insulation, stator coil, voltage, operating tests, winding
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THE INFLUENCE OF CUTTING PARAMETERS ON SURFACE QUALITY AND NITROGEN CONSUMPTION DURING LASER CUTTING

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201763
VACLAV MUSIL, MAREK SADILEK, ROBERT CEP, SARKA MALOTOVA
VSB-Technical University of Ostrava, Faculty of Mechanical Engineering, Ostrava, Czech Republic
e-mail: robert.cep@vsb.cz
Abstract
Unconventional machining methods, or also progressive machining methods, such as laser cutting, waterjet cutting, ultrasound machining, etc. are undergoing a very rapid development. Laser cutting machines often evaluate even 80 parameters in real time. Their advantage is the significantly higher productivity. Many values are defined by the machine manufacturer and can not be changed for a given laser. For custom laser cutting there are 2 essential parameters, adjustable depending on the process gas employed. The aim of this article is to find the setting that will reduce the consumption of process media while maintaining or improving the quality of the machined surface.
Keywords: laser cutting, consumption of process medium, nozzle diameter, process fluid pressure
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THE GENERATION OF ROBOT EFFECTOR TRAJECTORY AVOIDING OBSTACLES

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201764
MARTIN KOMAK, MARIAN KRALIK, VLADIMIR JERZ
Slovak University of Technology in Bratislava, Faculty of Mechanical Engineering, Institute of manufacturing systems, environmental technology and quality management, Bratislava, Slovak Republic

e-mail: martin.komak@stuba.sk
Abstract
This paper discusses the problem of trajectory planning for robotic manipulators at minimal cost. The paper deals with problems of obstacle avoidance during the manipulation and technological activities of the industrial robot. A system has been designed to find a trajectory that is both collision-free and of minimal distance. The goal is to reduce workplace costs with the robot and thus increase the efficiency of the robotized production cell. The work is mainly focused on the optimization of trajectory by planning the shortest path between robot targets. Also, when a trajectory is generated, the dynamic effects on the industrial robot are taken into account. Task solving isuniversaland is designed for several types of robot kinematic structures. The task comes under off-line robot programming.
Keywords: obstacle avoiding, trajectory planning, industrial robot, optimization, robot effector
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EFFECT OF STRUCTURAL PARAMETERS ON TEMPERATURE DISTRIBUTION OF ORGANIC LIGHT EMITTING DIODE PANELS

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201767
TOSHIRO KOBAYASHI1, TAIZO UCHIDA1, YUICHI UTSUMI2, HIDEYUKI KANEMATSU3, TSUYOSHI MASUDA4
1Tsuyama College, National Institute of Technology, Dept. of Electronics & Control Engineering, Okayama, Japan
2University of Hyogo,  Laboratory of Advanced Science and Technology for Industry, Akou-gun, Hyogo, Japan
3Suzuka College, National Institute of Technology, Dept. of Materials Science & Engineering, Suzuka, Mie, Japan
4Q-Light co., Ltd., Hanamaki, Iwate, Japan

e-mail : koba@tsuyama-ct.ac.jp
Abstract
This paper describes the temperature distribution of an organic light emitting diode (OLED) panel calculated by a finite element method (FEM) and measured. Organic LEDs (OLEDs or organic electro luminescence) are examples of solid-state lighting (SSL) that have been rapidly developed and applied in many practical fields owing to their high efficiency and on mercury-free operation. However, energy is lost as heat from OLEDs; therefore, a solution to the problems of heat transfer technology is important. It is preferable to operate an OLED below 50 °C in order to avoid degradation and change of colour at higher temperatures. Some of the authors have reported the influence of structure, materials, and dimensions on the temperature distribution of an OLED panel calculated by FEM [Kobayashi 2012&2014]. However, the analysis was conducted under a condition where heat radiation was neglected. In the present paper, both heat transfer and radiation were considered, then temperature distributions of an OLED panel having a glass substrate were measured by an infrared thermography. As a result, it was found that the maximum temperature of the OLED panel with a heat generation of 333 W/m2 was around 37 °C and the values obtained by one dimensional equations were consistent well with those obtained 3D-FEM analysis, and the temperature difference between the panel center and the end was around 14 °C. The estimation was verified by the measurement using thermography.
Keywords: OLED, organic LED, temperature, FEM, design of experiment, heat transfer
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ICE JET TECHNOLOGY

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201772
MARKO JERMAN1, ANDREJ LEBAR1,2, IZIDOR SABOTIN1, PAVEL DRESAR1, JOSKO VALENTINCIC1
1University of Ljubljana, Faculty of Mechanical Engineering, Slovenia
2University of Ljubljana, Faculty of Health Sciences, Slovenia

e-mail: marko.jerman@fs.uni-lj.si
Abstract
Ice jet technology also known as ice abrasive water jet (IAWJ) is a prototype technology currently under development. In IAWJ technology ice particles made from water are used instead of mineral abrasive. The aim is to increase the productivity of pure water jet (WJ) while keeping its advantages, producing no other waste product but water. Technology has great potential to be used in food and medical industries as well as other areas where cleanliness of the process and no additional waste product is of high priority. In order to use ice as an abrasive it has to be used at extremely low temperatures where its mechanical properties such as hardness become usable for machining applications. The paper presents the latest findings and achievements of IAWJ technology as well as the approaches and methodology used during its development. Two approaches to obtain ice particles in the water are studied, namely generation of ice particles in the cutting head during the machining process and generation of ice particles outside of the cutting head which are added to the jet similarly as in injection AWJ technology. The main challenge is to provide very cold and thus hard ice particles in the cutting zone where they are used as an abrasive and maintaining the system stability. It is therefore essential to monitor and control the temperatures occurring in the system. The presence of ice particles inside the jet could not be directly identified due to instrument limitations. Positive effect of ice on cutting efficiency was observed but could not be sufficiently studied due to instabilities present in the current state of the prototype.   
Keywords: IAWJ machining, IceJet, ice abrasive, cryogenic gas, ice particles
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APPLICATION OF WATER JET TECHNOLOGY FOR CONCRETE REPAIR

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201774
LENKA BODNAROVA1, LIBOR SITEK2, JOSEF FOLDYNA2, TOMAS JAROLIM1, RUDOLF HELA1
1Brno University of Technology, Faculty of Civil Engineering, Brno, Czech Republic
2Institute of Geonics of the CAS, Ostrava, Czech Republic

e-mail: bodnarova.l@fce.vutbr.cz
Abstract
This article brings selected knowledge from the long-term cooperation between the Brno University of Technology, the Faculty of Civil Engineering, the Institute of Technology of Building Materials and Components, and the Academy of Sciences of the Czech Republic, v.v.i., Institute of Geonics, Ostrava – Poruba in the field of the interaction of water jets and concrete, especially with regard to the use of water jet technology for the removal of surface layers of concrete during repair of concrete. Attention is paid to monitoring the quality of the concrete surface treated by water jet technology and creating a relief in concrete to achieve good cohesion of concrete with repair mortar. The absence of cracks in the concrete structure after water jet blasting has been proven.
Keywords: Water jet (WJ), concrete, concrete repair, X-ray computer tomography (X-ray CT), micro cracks, tensile strength
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SOLAR ABSORBERS WITH A STRUCTURED SURFACE

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_2017102
JAN RIHACEK1, MARTIN SARBORT2, PETR HORNIK1, 2,LIBOR MRNA1, 2
1Brno University of Technology, Faculty of Mechanical Engineering, Institute of Manufacturing Technology, Brno, Czech Republic
2Institute ofScientific Instruments ofthe Czech AcademyofSciences, Brno, Czech Republic

e-mail: rihacek.j@fme.vutbr.cz
Abstract
The article deals with the issue of a new type of solar absorbers, which have a direct flow structure and a structured surface, which consists of pyramidal cavities. This solution increases a thermal efficiency. In the first part, possible parameters that affect the thermal efficiency of solar collectors are described and further, a simulation of a dependence of a resulting absorption coefficient at a pyramidal apex angle and daytime or season is performed. For this purpose a simulation program was developed in the MATLAB software environment by using the Monte Carlo method. The second part of the paper deals with the possibilities of production of the solar absorber with the structured surface, mainly by using the pillow hydroforming technology. The production process is simulated in ANSYS software. In this case, an austenitic chromium nickel stainless steel X5CrNi18-10 is used as a material for the production of solar absorbers.
Keywords: solar absorber, numeric simulation, hydroforming, , X5CrNi18-10 steel, MATLAB, ANSYS, LS-DYNA
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APPROACHES TO THE EVALUATION OF WORKSHOP MICROCLIMATE CONDITIONS

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_2017107
RUZENA KRALIKOVA1, FRANTISEK KOBLASA2
1Technical University of Kosice, Kosice, Slovak Republic
2Technical University of Liberec, Liberec, Czech Republic

e-mail: ruzena.kralikova@tuke.sk
Abstract
The article deals with the evaluation of microclimate conditions at the workplaces of the engineering workshops. By measuring the conditions of the thermo-humidity parameters, these were objectified and compared with the results of the subjective evaluation, obtained by the questionnaire survey. Based on investigators' research up to the present day, these outputs are not always consistent, and therefore the research objective was to look for narrow spots of this "disagreement".  Appropriate workplace conditions "well-being" are indispensable for  a manufacture production, as workers are the most valuable resource of the company, which is still true, at of today's high automation, and at the onset of the so-called "4th industrial revolution", the employees health protection must be ensured above all, because workplace comfort is affecting not only a health, but also a productivity of employees.
Keywords: Thermal comfort, microclimate, environment, measurement, questionary survey
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MANUFACTURING METHOD OF SPIRAL BEVEL GEARS BASED ON CAD/CAM AND 3-AXIS MACHINING CENTER

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_2017113
NGUYEN VAN TUONG
Nha Trang University, Faculty of Mechanical Engineering, Department of Manuafacturing Engineering, Nha Trang, Viet Nam
e-mail: tuongnv@ntu.edu.vn
Abstract
Spiral bevel gears have been traditionally machined on special machines commonly known as Gleason, Oerlikon, or Klingelnerg. One of disadvantages of the traditional method is high cost. This paper presents a practical method based on CAD/CAM and 3-axis CNC machining to manufacture spiral bevel gears of the Gleason design. This method can be considered as an alternative method to the traditional methods. For the proposed method, first, the 3D model of the spiral bevel gear was created. Next, the tool path planning for 3-axis cutting of the tooth profiles of the gear was performed. Then, the gear teeth were cut on a 3-axis CNC machining centre using flat-end mills for roughing and semi-finishing, and ball-end mills for finishing. The machined gear was measured and analysed by a non-contact measuring method which allows to compare the actual part to the nominal CAD model. The pitch deviations and the surface roughness of the manufactured gear were also measured.  As a result, the validity and effectiveness of the proposed method were confirmed.
Keywords: CAD/CAM, spiral bevel gear, gear manufacturing, 3-axis machining centre, end mill, optical scanner
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CONFIGURATION ON HYBRID PLATING TO IMPROVE INTERNAL FIXATION ON FEMUR BONE MODEL

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_2017120
NAFISAH ARINA HIDAYATI, MOCH. AGUS CHOIRON, SOFYAN ARIEF SETYABUDI
Brawijaya University, Mechanical Engineering Department, Malang, Indonesia
e-mail : nafisah@ub.ac.id, agus_choiron@ub.ac.id, sasbudi@ub.ac.id
Abstract
This study presents a stress analysis of hybrid plating constructions on femur fracture. The bone screw mounting configurations have successfully modeled with ANSYS Multiphysics/LS-Dyna v.18.1. The bone model was achieved from the CT-scanning of the human femur bone. The interactions between femur bone and hybrid plating were observed. Locking compression plates with 8 holes for bone screws were used. Applied axial compression load has developed stress distribution at all segments. Locking screws endured the bending forces and generated bending moment. Stress concentrations were noticeable at the screws neck. Nonlocking screws have produced a lower stress but bearing to be loosed since has small angular rigidity due to unthreaded screw heads. The most stable bone screw configuration was model A with N-L-N-L L-N-L-N pattern. The alternating sequence of screw configuration resulted in lower stress distribution at all segments, has small screw displacements and enduring lowest stress at each segment, especially femur bone.
Keywords: Femur fracture, hybrid plating, configuration, stress, locking compression plate, internal fixation, bone screw
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CORROSION CHARACTERIZATION OF ANODIZED AA 6061

MM (Modern Machinery) Science Journal, June_2018
DOI: 10.17973/MMSJ.2018_06_201803
PUTU HADI SETYARINI1, RUDY SOENOKO1, YUDY SURYA IRAWAN1, PURNOMO2
1Brawijaya University, Faculty of Engineering, Mechanical Engineering Department, Malang, Indonesia
2Universitas Muhammadiyah Semarang, Faculty  of Engineering, Mechanical Engineering Department, Semarang, Indonesia

e-mail: putu_hadi@ub.ac.id
Abstract
In this study we examined the effect of topography and corrosion resistance of aluminum alloy 6061 which has been anodized on a mixture of phosphoric acid and oxalic acid by using titanium cathode. Surface topography was tested with the N8 NEOS Bruker, corrosion testing performed by Tafel method using a potentiostat Autolab (PGSTAT302N), while testing the immersed test to determine the condition of the surface corroded done using 3.5% NaCl fluids with immersion time of 500 hours. The results obtained indicate that the change in the surface is affected by the potential applied during anodization process. Increasing the potential shown to improve the contour of the growing prevalence of pore sizes formed after the anodizing process. The corrosion resistance is also increased with increasing potential.
Keywords: surface topography, potential, corrosion resistance, anodizing, AA 6061
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