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Streamlining of the production of a component into the aircraft engine
Bula, Tomáš ; Sliwková, Petra (referee) ; Polzer, Aleš (advisor)
The thesis deals with innovation of the technological process of casting called Fan support in the company Honeywell Aerospace Olomouc s.r.o. The first part of the thesis is dedicated to component description which is made of titanium alloy Ti-6Al-4V. The section is also devoted to jet engine TFE 731, which is the engine where our particular component has specific function. Another part is focused on theoretical analysis of material characteristics of titanium alloys and their machinability. In the following section there are considered alternatives of machine suppliers with subsequent selection of the multifunctional CNC milling-turning center DMC 80 U duoBLOCK equipped with Jetstream technology. The transfer of the production to another machine is accompanied by an innovation of the technological process, making new fixtures and optimalization of the cutting tools. The section is also dedicated to static analysis of the component in operation 7 supported by finite element method (FEM). The final part of the thesis includes evaluation of the costs and savings achieved by innovation of the technological process.
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High entropy alloy preparation by means of mechanical alloying
Gamanov, Štěpán ; Krajňáková, Petra (referee) ; Moravčík, Igor (advisor)
This thesis deals with topic of high entropy alloys. The teoretical part explains what are high entropy alloys, how are they different from conventional alloys, how is their chemical composition proposed and what potencial these alloys have. The experimental part describes procedures of preparation of three high entropy alloys witch consists of Co, Cr, Fe, Ni and Ti, where the concentration of all elements except Ti remains the same. These alloys were prepared via mechanical alloying and sintered by SPS process. Crucial part of this thesis is characterization of these three alloys with EDS and XRD supported by hardness measuring and tensile tests.
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Study of CeOx / Rh inverse catalyst
Kettner, Miroslav ; Nehasil, Václav (advisor) ; Johánek, Viktor (referee)
Title: Study of CeOX / Rh inverse catalyst Author: Bc. Miroslav Kettner Department: Department of Surface and Plasma Science Supervisor: doc. RNDr. Václav Nehasil, Dr., Department of Surface and Plasma Science Abstract: Inverse catalysts of cerium oxide deposited on polycrystalline and monocrystalline (111) rhodium substrates were studied by means of surface science experimental methods. Growth characteristics of cerium oxide were investigated in dependence on deposition conditions and different thickness determination methods were compared. Acording to oxidizing or reducing exposition conditions changes in degree of oxidation of CeOX were observed. Further spectra analysis showed additional Ce-Rh alloy formation. Adsorption positions CO on-top and CO hollow on Rh (111) surface were differentiated by spectra fitting procedures. Oxygen absorption and reverse desorption in CeOX was confirmed. Performed experiments indicate that this process occurs through oxide-metal interface. CO oxidation reaction mechanisms at room temperature were proposed. Cerium oxide presence is necessary for reaction occurrence. Significant influence of deposited CeOX on proposed CO oxidation reaction mechanisms was proved by this way. Keywords: Rhodium, cerium oxide, alloy, inverse catalyst, CO oxidation.
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Aspekty dynamického namáhání korozně poškozených Al-Cu slitin
Kreslík, Roman
Diploma thesis called Aspects of dynamic strain of corrosion-damaged Al-Cu alloys is focused on the problems of mechanical dynamic strain and corrosion degradation. The theoretical part of the thesis consists of several chapters dealing with general problems of aluminum, its alloys, copper, corrosion and mechanical strain, especially the load with rapidly changing force. The practical part of the thesis is focused on experimental verification of quasidynamic fracture behavior of Al-Cu alloy (designation EN AW 2007 T4), namely examination of impact strength by means of the Charpy hammer test according to ČSN EN 10 045-1 and corrosion degradation of this alloy according to ČSN 03 8101, ČSN EN ISO 7539-1 (038172). The test confirmed the negative effect of corrosion exposure on the impact strength of the selected aluminum alloy.
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High entropy alloy preparation by means of mechanical alloying
Gamanov, Štěpán ; Krajňáková, Petra (referee) ; Moravčík, Igor (advisor)
This thesis deals with topic of high entropy alloys. The teoretical part explains what are high entropy alloys, how are they different from conventional alloys, how is their chemical composition proposed and what potencial these alloys have. The experimental part describes procedures of preparation of three high entropy alloys witch consists of Co, Cr, Fe, Ni and Ti, where the concentration of all elements except Ti remains the same. These alloys were prepared via mechanical alloying and sintered by SPS process. Crucial part of this thesis is characterization of these three alloys with EDS and XRD supported by hardness measuring and tensile tests.
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Study of CeOx / Rh inverse catalyst
Kettner, Miroslav ; Nehasil, Václav (advisor) ; Johánek, Viktor (referee)
Title: Study of CeOX / Rh inverse catalyst Author: Bc. Miroslav Kettner Department: Department of Surface and Plasma Science Supervisor: doc. RNDr. Václav Nehasil, Dr., Department of Surface and Plasma Science Abstract: Inverse catalysts of cerium oxide deposited on polycrystalline and monocrystalline (111) rhodium substrates were studied by means of surface science experimental methods. Growth characteristics of cerium oxide were investigated in dependence on deposition conditions and different thickness determination methods were compared. Acording to oxidizing or reducing exposition conditions changes in degree of oxidation of CeOX were observed. Further spectra analysis showed additional Ce-Rh alloy formation. Adsorption positions CO on-top and CO hollow on Rh (111) surface were differentiated by spectra fitting procedures. Oxygen absorption and reverse desorption in CeOX was confirmed. Performed experiments indicate that this process occurs through oxide-metal interface. CO oxidation reaction mechanisms at room temperature were proposed. Cerium oxide presence is necessary for reaction occurrence. Significant influence of deposited CeOX on proposed CO oxidation reaction mechanisms was proved by this way. Keywords: Rhodium, cerium oxide, alloy, inverse catalyst, CO oxidation.
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Assessment of Factors Influencing Wear Resistance of Metallic Materials
Cieslar, Jiří ; Brožek, Milan (advisor) ; Jan, Jan (referee)
This thesis investigates the suitable chemical composition of a iron alloy with improved wear resistance. A unique set of alloys with a specifically designated chemical composition was manufactured for experiments. Their properties in defined abrasive conditions was studied in laboratory conditions. Wear resistance was determined on an experimental bench with bound particles. Material properties description was always complemented with information gained during material metallographic structure investigations. All the results were compared with results achieved for commercially available weld deposition materials (specifically designated for abrasion conditions). These (weld deposition) materials were subjected to an identical set of laboratory experiments and additionally to a set of experiments under inservice conditions.
This thesis offers new knowledge about the relationship between material hardness, material structure and wear resistance. The outlined results also give evidence about the correlation between results gained under laboratory conditions and those gained under in-service conditions (in relation to material structure and hardness).
At the end of the thesis the knowledge gained from these experiments is applied to a specific application the service life extension of plough blade segments. On this basis a new material is designed which will extend service life without additional demands on the costs, and the approach to the renovation of worn plough blade segments is justified.
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Streamlining of the production of a component into the aircraft engine
Bula, Tomáš ; Sliwková, Petra (referee) ; Polzer, Aleš (advisor)
The thesis deals with innovation of the technological process of casting called Fan support in the company Honeywell Aerospace Olomouc s.r.o. The first part of the thesis is dedicated to component description which is made of titanium alloy Ti-6Al-4V. The section is also devoted to jet engine TFE 731, which is the engine where our particular component has specific function. Another part is focused on theoretical analysis of material characteristics of titanium alloys and their machinability. In the following section there are considered alternatives of machine suppliers with subsequent selection of the multifunctional CNC milling-turning center DMC 80 U duoBLOCK equipped with Jetstream technology. The transfer of the production to another machine is accompanied by an innovation of the technological process, making new fixtures and optimalization of the cutting tools. The section is also dedicated to static analysis of the component in operation 7 supported by finite element method (FEM). The final part of the thesis includes evaluation of the costs and savings achieved by innovation of the technological process.
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