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Nickel alloys in aerospace
Šprincl, Jan ; Nopová, Klára (referee) ; Němec, Karel (advisor)
The aerospace industry is one of the fastest growing industries today. Increasing demands on the efficiency and fuel consumption of jet engines can be met, among other things, by using higher quality materials, which clearly include nickel-based superalloys, which can meet these demands. This work provides an overview of these materials: both the building block of the whole structure - nickel, superalloys in general, and especially those nickel-based. It deals with the composition of the microstructure formed by the austenitic matrix ( phases) most often cured by carbide or substitution precipitates, unique mechanical properties, but also the influence of high temperatures and creep on the degradation of these properties. The work also includes a comparison of selected superalloys from different perspectives, especially according to the type of particles that cure the matrix or the effect of loading on the superalloy in the presence of thermal oxidation environment. Depending on the area of application, these materials are predestined for further future development and improvement, because their unique properties in areas with extreme conditions are irreplaceable for the time being.
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Basic Mechanism of Fatigue and Combined Fatigue/Creep Damage of Ni-based Superalloys MAR-M 247 and IN 713LC
Horník, Vít ; Kohout, Jan (referee) ; Pantělejev, Libor (referee) ; Kunz, Ludvík (advisor)
The thesis is focused on clarifying fatigue damage mechanisms and fatigue-creep damage mechanisms of MAR-M 247 and IN 713LC polycrystalline Ni-based superalloys. This thesis begins with basic information about nickel-based superalloys and their microstructure, followed by a description of fatigue and creep mechanisms and their mutual interaction. The next part contains experimentally obtained results describing the behavior of MAR-M 247 and IN 713LC superalloys under various sets of conditions. Three testing temperatures - 800, 900 and 950 °C were used for the measurement of fatigue properties under symmetrical loading cycle, because in the temperature range 800 – 950 °C, the mechanism of fatigue crack propagation of both superalloys should change from the originally crystallographic at "lower" temperatures (800 °C) to non-crystallographic at "higher" temperatures (950 °C). In addition the effect of processing technology on fatigue properties was studied on the superalloy IN 713LC. High-frequency cyclic loading (about 120 Hz) with high mean stress at elevated temperatures was applied to induce fatigue-creep interaction. The combined fatigue-creep loading was performed on the IN 713LC superalloy at 800 °C and on the MAR-M 247 superalloy at 900 °C.
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Study of AlSi protective coating after degradation
Vítková, Gabriela ; Řičánková, Veronika (referee) ; Hutařová, Simona (advisor)
Materials used for high temperature applications works in a very aggressive environment (oxidation, hot corrosion, erosion, fatigue, creep). Demands on these materials are very high. Nickel-based superalloys show the certain stability in this environment. Improved resistance to oxidation and hot corrosion can be achieved by using protective layers such as diffusion barriers. This thesis is focused on changes of microstructure and properties of AlSi layer applied by „slurry“ method on nickel-based superalloy Inconel 713 LC, due to long-term thermal exposition at 800, 900 a 1000 °C.
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Analysis of the influence of temperature cycles on the elimination of recast layer on materials used in aerospace
Slavíková, Barbora ; Martin,, Grepl (referee) ; Horník, Vít (advisor)
This bachelor thesis is dealing with the analysis of the influence of temperature cycles on the elimination of recast layer on materials used in aerospace. This thesis was created in cooperation with Honeywell Aerospace Company in Olomouc. The aim of this work was to prepare the study about influence of the brazing heat cycle on recast layer removing which was caused by laser cutting process. In first part of this bachelor thesis the unconventional machining methods, materials and related brazing processes used in Honeywell Aerospace Olomouc were described. Second part of the thesis consists of experimental measurement of the recast layer provided on a test specimens including their evaluation and interpretation of the results. The conclusions of this bachelor thesis will be used as future reference for next technological research in Honeywell Aerospace Company in Olomouc.
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Nickel alloys in aerospace
Šprincl, Jan ; Nopová, Klára (referee) ; Němec, Karel (advisor)
The aerospace industry is one of the fastest growing industries today. Increasing demands on the efficiency and fuel consumption of jet engines can be met, among other things, by using higher quality materials, which clearly include nickel-based superalloys, which can meet these demands. This work provides an overview of these materials: both the building block of the whole structure - nickel, superalloys in general, and especially those nickel-based. It deals with the composition of the microstructure formed by the austenitic matrix ( phases) most often cured by carbide or substitution precipitates, unique mechanical properties, but also the influence of high temperatures and creep on the degradation of these properties. The work also includes a comparison of selected superalloys from different perspectives, especially according to the type of particles that cure the matrix or the effect of loading on the superalloy in the presence of thermal oxidation environment. Depending on the area of application, these materials are predestined for further future development and improvement, because their unique properties in areas with extreme conditions are irreplaceable for the time being.
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Basic Mechanism of Fatigue and Combined Fatigue/Creep Damage of Ni-based Superalloys MAR-M 247 and IN 713LC
Horník, Vít ; Kohout, Jan (referee) ; Pantělejev, Libor (referee) ; Kunz, Ludvík (advisor)
The thesis is focused on clarifying fatigue damage mechanisms and fatigue-creep damage mechanisms of MAR-M 247 and IN 713LC polycrystalline Ni-based superalloys. This thesis begins with basic information about nickel-based superalloys and their microstructure, followed by a description of fatigue and creep mechanisms and their mutual interaction. The next part contains experimentally obtained results describing the behavior of MAR-M 247 and IN 713LC superalloys under various sets of conditions. Three testing temperatures - 800, 900 and 950 °C were used for the measurement of fatigue properties under symmetrical loading cycle, because in the temperature range 800 – 950 °C, the mechanism of fatigue crack propagation of both superalloys should change from the originally crystallographic at "lower" temperatures (800 °C) to non-crystallographic at "higher" temperatures (950 °C). In addition the effect of processing technology on fatigue properties was studied on the superalloy IN 713LC. High-frequency cyclic loading (about 120 Hz) with high mean stress at elevated temperatures was applied to induce fatigue-creep interaction. The combined fatigue-creep loading was performed on the IN 713LC superalloy at 800 °C and on the MAR-M 247 superalloy at 900 °C.
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Analysis of the influence of temperature cycles on the elimination of recast layer on materials used in aerospace
Slavíková, Barbora ; Martin,, Grepl (referee) ; Horník, Vít (advisor)
This bachelor thesis is dealing with the analysis of the influence of temperature cycles on the elimination of recast layer on materials used in aerospace. This thesis was created in cooperation with Honeywell Aerospace Company in Olomouc. The aim of this work was to prepare the study about influence of the brazing heat cycle on recast layer removing which was caused by laser cutting process. In first part of this bachelor thesis the unconventional machining methods, materials and related brazing processes used in Honeywell Aerospace Olomouc were described. Second part of the thesis consists of experimental measurement of the recast layer provided on a test specimens including their evaluation and interpretation of the results. The conclusions of this bachelor thesis will be used as future reference for next technological research in Honeywell Aerospace Company in Olomouc.
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On the cutting of cast superalloys
Metelková, Jitka ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
This work deals with the issue of defects generation during the separation of the castings from a nickel-based superalloy, Inconel 738LC. The technology of investment casting is presented, followed by a description of metallurgy of superalloys, their physical and mechanical properties, as well as their technical applications. The machinability of superalloys and method of castings separation were also described as well as some of the casting defects that were reported to have impact on the generation of the defects after cutting. In the experimental part, the material microstructure and casting defects were analyzed. The experimental machining part consisted first of a comparative study of the friction sawing and plasma arc cutting technology at the standard operating conditions actually used in production. Second, an optimization study for the friction sawing was carried out, with a special focus on the suitability of an alternative cutoff wheel for the chosen application. Application of this wheel allows reducing the security distance between the cut and the part, thus reducing the production cost of the part.
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Establishment of cutting conditions for selected aircraft parts
Baron, Yoann ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
Tato práce obsahuje přehled superslitin na bázi niklu, jejich obrábění za vysokého tlaku chladicí kapaliny, týká se také metod optimalizace pro tento typ obrábění a následné analýzy opotřebení nástroje. Tato studie byla vytvořena ve spolupráci se společností Safran, experimentální část byla zrealizována ve výrobním závodě Evry-Corbeil ve Francii. Experimentální část práce se týká optimalizace řezných podmínek pro vnitřní hrubovací soustružení součástí pro letecký průmysl za vysokého tlaku chladicí kapaliny. Cíle práce byly následující: srovnání rozdílných vyměnitelných břitových destiček dodaných společností Safran, návrh hrubovacích strategií a určení optimálních podmínek pro každou z vybraných strategií. Byly uvažovány dvě rozdílné strategie: soustružení s konstantním posuvem a šířkou záběru ostří a tzv. „ramping“. Pro každou ze strategií byla provedena operace čelního a podélného soustružení. Výsledky byly porovnány na základě ekonomického a produktivního kritéria.
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Study of AlSi protective coating after degradation
Vítková, Gabriela ; Řičánková, Veronika (referee) ; Hutařová, Simona (advisor)
Materials used for high temperature applications works in a very aggressive environment (oxidation, hot corrosion, erosion, fatigue, creep). Demands on these materials are very high. Nickel-based superalloys show the certain stability in this environment. Improved resistance to oxidation and hot corrosion can be achieved by using protective layers such as diffusion barriers. This thesis is focused on changes of microstructure and properties of AlSi layer applied by „slurry“ method on nickel-based superalloy Inconel 713 LC, due to long-term thermal exposition at 800, 900 a 1000 °C.
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