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Surface treatment methods applied to 3D printed samples and their analysis
Rygl, Michal ; Dobrocký, David (referee) ; Sedlák, Josef (advisor)
The presented paper deals with the issue of smoothing parts produced using FFF 3D printing technology. The aim of the paper was to compare technical surface treatment methods and economic side. Emphasis was placed especially on the degree of reduction of surface roughness while maintaining an acceptable level of process costs. Chemical smoothing, local CO2 laser melting, tumbling and surface treatment based on filler spraying were used to smooth the plastic prints. Prints made of ABS, PLA, PolySmooth and PolyCast were subjected to the smoothing process. Printing parameters were first determined for individual materials and test samples were produced on their basis. After determining the process parameters for individual surface treatment methods, the finished surfaces were measured with a profilometer. Based on the results, the chemical etching method was evaluated as the most effective surface smoothing method. Due to the etching of the surface layer of the sample made of PolySmooth material, the surface roughness parameter Sa was reduced in diameter compared to the reference sample. by 99,56 %. The least effective method was tumbling technology, which showed an average roughness reduction of 30,07 % in the case of ABS. However, the technology based on grinding parts with grinding stones had the lowest process costs for finishing the samples. Technical The economically best choice of all tested combinations was the technology of chemical etching of ABS polymer prints. The results and conclusions of the work will serve not only to select the finishing operation and material for specific applications of prints in practice, but also to expand the possibilities of using additively produced components.
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Sedimentation reservoir on the stream Kuřimka
Holá, Lucie ; Julínek, Tomáš (referee) ; Uhmannová, Hana (advisor)
The goal of the bachelors work is a proposal of sedimentation tank on Kuřimka in the cadestral area of Moravské Knínice. In calculations there was made capacity of addressed section and calculation of levels for thirty-days water and selected N-year flow. One of the chapters was dedicated to evaluation of vegetative suite. For calculations there was used one-dimensional mathematical model HEC-RAS 4.1. Determination of roughness of bottom and slopes was based on personal visit. The result is determination of capacitive flow, evaluation of current state and proposal of sedimentation tank on the chosen estate. Bachelors work can be a contribution to another sedimentation tank in the area of Brněnská dam.
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Prediction of suitable cutting conditions for machining of main steels
Beneš, Ondřej ; Fiala, Zdeněk (referee) ; Jaroš, Aleš (advisor)
In this thesis is described machining of barrel steels and determination of the most suitable cutting conditions for this process. In the theoretical part was characterized cutting process and explained problems of VBD wear, chip formation and roughness of the surface. There were also explained most common cutting materials and in the last part were described CVD and PVD coating methods. In the experimental part was measured force load during turning. There was also tested eight carbide cutting inserts from SECO TOOLS. During the tests were measured additional surface roughness values and taken chip samples as well. From the evaluated load force data were determined optimized cutting conditions for machining barrel steels and most suitable type of cutting insert.
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Model of surface profile after milling operation with plain milling cutter
Horváth, Ľudovít ; Kubík, Roman (referee) ; Zemčík, Oskar (advisor)
In the teoretical part of the master´s thesis, the master´s thesis deals with milling and surface profile describing. In the practical part, the master´s thesis deal with model of surface profile after milling operation with plain milling cetter. For evalution were used data obtained from the computer model of the surface profil and data obtained from measuring the actual surface profil, which was created by machining the material mills with a diameter of 45 mm.
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Techniques of thin layers deposition and characterization, their analysis using scanning electron microscopy
Kiška, Roman ; Moravčík, Igor (referee) ; Čupera, Jan (advisor)
My thesis is concerned with the application of thin films methods and it focuses on the method of PVD and CVD. Another part of my work is experimental, where two samples were preapared by magnetron sputtering and by method of gas phase deposition. The aim of the work was to compare their material properties with commercially produced samples. Severel parts were measured - nanohardness, adhesion, roughness and thickness. Theoretical part focuses on chemical and physical essence of the different methods of the deposition of thin films and on the description of material properties, that are essential for thin films. The practical part includes the description of depositional processes and of the characteristic techniques used in the practical part.
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Factors affecting the quality of machined surfaces after milling operation
Černý, Libor ; Jaroš, Aleš (referee) ; Fiala, Zdeněk (advisor)
This diploma thesis deals with the final quality of the surface under variable working conditions during milling. The first part deals with the definition of qualitative parameters describing surface properties. This is followed by a brief description of the cutting resistance measurements. The thesis is complemented by experimental verification using front milling and its evaluation. The aim of the experiment is to determine the dependence of the surface quality and the size of cutting resistors under the variable working conditions of the machine that do not make a common part of the manufacturing processes.
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Calibration of roughness standards
Šrůt, Petr ; Hammer, Miloš (referee) ; Jankových, Róbert (advisor)
This master´s thesis deals with the measurement of surface roughness on a roundness instrument Talyrond TR595S. The aim was to expand possibilities of measuring on this roundness instrument. The main benefit of this thesis is creation of the proposal for the roughness measurement components in a horizontal and vertical plane. Thesis also includes the procedure for measuring of the roughness of the circular components including calculation of measurement uncertainty.
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The influence of coatings on fracture behaviour of ledeburitic steel
Šafář, Martin ; Jurči,, Peter (referee) ; Hadraba, Hynek (advisor)
This work deals with tool steel Vanadis 6. It describes the preparation of samples for the three-point bending test, with which it examines the influence of surface roughness, the effect of nitriding, coating and duplex coatings on fracture behaviour of the steel. First, it examines bending strength and the total energy required to work of fracture. The work also includes mapping and measurement of surface roughness on different layers. This measurement is performed on a confocal microscope.
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Vliv reologických vlastností nátěrových hmot na transparetní povrchové úpravy
Karadinović, Ana
The master thesis deals with the influence of the rheological properties of coating materials on the surface finishing properties. The main rheological properties which were analyzed are viscosity and flow time of the coatings. Water-based, wax and polyurethane coatings were used. The aim was to determine the effect of temperature and dilution of the coatings on their rheological properties. Used coatings were prepared with different properties and applied on different substrates. Laboratory tests of physical-mechanical, chemical and visual properties were carried out. The influence of the rheological properties of the coatings on the properties of the surface finishing was analyzed based on the results of the laboratory tests.
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Evaluation of the quality of laser cutting surfaces
Krejčiřík, Marek ; Sigmund, Marian (referee) ; Kubíček, Jaroslav (advisor)
As the title implies, the topic to be solved in this diploma thesis was describing and evaluating the CO2 and fiber laser cutting technologies and their comparison with plasma and oxygen cutting, described in the standard ČSN EN ISO 9013. Samples of IMEX 700 high-strength fine-grain steel with a yield strength of 690 MPa were used and subjected to a final quality assessment. The diploma thesis is divided into two parts – theoretical and experimental. The theoretical part is mainly focused on a laser. Among other things, the principle of plasma and oxygen cutting was discussed. The cutting edges of samples cut by these methods were analyzed and compared in an experiment. Last but not least, the surface roughness, material hardness, and their measurement methods were discussed in the theoretical part. The final cuts after laser, plasma, and oxygen cutting were evaluated and compared in the experimental part. The roughness of the individual cuts was compared, and measured values were classified into the relevant quality classes specified by the standard EN ISO 9013. The thermal influence of the cutting joint, the width of the thermally influenced area and the hardness history were further evaluated parameters. The obtained results were discussed and summarized in the conclusion. Studied technologies were compared. Based on the experiment, fiber laser cutting was determined as the best choice regarding quality and economics.
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