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Production of a part of the TV bracket
Opravil, Petr ; Kocich, Radim (referee) ; Podaný, Kamil (advisor)
Master’s thesis is focused on the design of the production of a part of the TV bracket. Part is made of steel sheet with thickness of 2,5 mm. The structural steel S 235 JRG1 was chosen as the most suitable material with following powder coating. From the possible variants, the production by progressive forming tool was chosen with respect to production requirements and a series size of 25 000 pieces by year. Part will be made in seven steps and it will require total force of 2 500 kN. Production will be realized on a mechanical eccentric press KSTU 3150-25-F3-P-SE from ANDRITZ Metals with maximum force of 3 150 kN.
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Elimination of oxide rising during aluminum alloys welding
Vagunda, Pavel ; Kocich, Radim (referee) ; Sigmund, Marian (advisor)
This diploma thesis deals with the search of reason causing production of oxides in the welded joint, which have an impact on defects formation. The objective was to identify the areas in the technological process that can have the biggest impact on the oxides generation. The following areas of the technology process were selected: the length of storage time, the influence of the welder and the participation of the arc cleaning effect. The simulation imitating these effects was processed on Y and HY type welds with incomplete penetration. Subsequently, macroscopic inspection was provided to supply the most data used for evaluation. Defects in the root of the weld, caused by the oxides formation, appeared in the majority of the samples. From the evaluation was concluded, that the highest elimination is achieved by a significantly increased cleaning effect of the arc. Other influences didn‘t prove significant difference. The results were followed by an evaluation and solution proposal. The best solution seems to be adjusting the location of the weld on the blank, so that the weld root is fully penetrated. As a result, the welded joint isn‘t subject to the negative effects associated with oxides.
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Manufacture of furniture console
Andrle, David ; Kocich, Radim (referee) ; Žák, Ladislav (advisor)
The work focuses on designing a technology for the production of a furniture console. A sheet metal component made of steel 11 321 with a thickness of 1 mm was proposed, and it is manufactured in an annual series of 10,000 pieces. A literary study was conducted to develop the manufacturing technology for this component, which combines cutting and bending in a combined progressive tool. Technological calculations were performed to design the appropriate tool, and a suitable machine was selected based on the total forming force. As a forming machine, the eccentric press LEXN 100 C was chosen.
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Elimination of oxide rising during aluminum alloys welding
Vagunda, Pavel ; Kocich, Radim (referee) ; Sigmund, Marian (advisor)
This diploma thesis deals with the search of reason causing production of oxides in the welded joint, which have an impact on defects formation. The objective was to identify the areas in the technological process that can have the biggest impact on the oxides generation. The following areas of the technology process were selected: the length of storage time, the influence of the welder and the participation of the arc cleaning effect. The simulation imitating these effects was processed on Y and HY type welds with incomplete penetration. Subsequently, macroscopic inspection was provided to supply the most data used for evaluation. Defects in the root of the weld, caused by the oxides formation, appeared in the majority of the samples. From the evaluation was concluded, that the highest elimination is achieved by a significantly increased cleaning effect of the arc. Other influences didn‘t prove significant difference. The results were followed by an evaluation and solution proposal. The best solution seems to be adjusting the location of the weld on the blank, so that the weld root is fully penetrated. As a result, the welded joint isn‘t subject to the negative effects associated with oxides.
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WE43 BIOCOMPATIBLE ALLOY AFTER SEVERE PLASTIC DEFORMATION: STRUCTURE CHARACTERIZATION
Kunčická, Lenka ; Král, Petr ; Dvořák, Jiří ; Kocich, R.
The report presents results of the analyses of biocompatible WE 43 Mg-based alloy processed by friction stir processing (FSP) at two different rotational speeds of 400 RPM, and 1200 RPM. The structures were observed by scanning electron microscopy (SEM), electron backscattered diffraction (EBSD). Observations were primarily focused on characterizations of grains and textures, supplementary testing of mechanical properties was performed via tensile tests. The results of low angle grain boundaries fractions and grain sizes showed that both the processing methods led to significant grain refinement and recrystallization, the average grain diameter within the 1200 RPM sample was less than 2 μm. Texture observations showed slight tendencies of the grains to align in the {0001}〈101̅0〉 and {0001}〈112̅0〉 preferential orientations, however, the maximum intensities were only about two times random. Supplementary tensile tests confirmed the positive effects of FSP on structures and properties of both the samples.
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THE INFLUENCE OF CONSOLIDATION PROCEDURE PARAMETERS ON COMPACTION OF AL POWDER
Lowe, T. C. ; Kunčická, L. ; Kocich, R. ; Davis, C. F. ; Hlaváč, L. ; Dvořák, Jiří
The influence of different consolidation procedures on compaction of Al powders was evaluated. Powder preparation procedures consisted of selection of particle size distribution, cold isostatic pressing (CIP), and vacuum sintering. Processing parameters investigated included the number of compression steps, compression pressure, and sintering temperature and time. Densities of the samples after compression and also after sintering were measured and compared. The overall oxygen content was analysed using by Energy Dispersive Spectroscopy. Phase composition was determined using X-ray. Microhardness measurements were performed to evaluate the degree of compaction. Double-step CIP at 200+300 MPa and subsequent sintering at 500°C for 60 min produced the best combination of properties from all the consolidation technologies of Al particles. Of the particle size ranges studies, those with diameters between 20 and 45 μm produced the best results. Aluminum oxide was present in the structure after all the processing treatments.
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