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Friction and lubrication of total hip replacement produced by 3D metal printing technology
Uhrová, Simona ; Horák, Zdeněk (referee) ; Vrbka, Martin (advisor)
This thesis investigates the tribological properties of total hip replacements manufactured by both traditional and additive technologies. The primary objective is to assess the impact of different manufacturing methods on friction and lubrication at the contact between the joint head and the acetabular cup. Techniques such as a pendulum joint simulator and optical methods are utilized to analyse the lubricant film formation and friction coefficient. The findings indicate that additively manufactured implants can potentially offer comparable or superior tribological properties compared to traditional methods, potentially leading to enhanced longevity and functionality of the implants. However, the need for appropriate surface treatment and further research into wear to ensure extended life and improved implant functionality is emphasised.
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Wear model of material couple at high temperatures
Rychlý, David ; Adam, Ondřej (referee) ; Němec, Karel (advisor)
Hlavním cílem práce bylo vytvořit model opotřebení materiálové dvojice za vysokých teplot pro predikci opotřebení kinematického mechanismu na turbodmychadle. Predikce opotřebení je komplexní proces, kterého se účastní mnoho chemických, fyzikálních a mechanických jevů, a proto není jednoduché jej analyticky počítat. Tato práce se vydává naproti tomuto problému pomocí empirických vztahů z literatury a aplikace principů a algoritmů strojového učení (machine learning) postaveného na datech z experimentu. Empirické vztahy i metody strojového učení jsou v práci podrobeny důkladné rešerši a aplikovány na dostupná data z firmy Garrett Motion. Práce kriticky hodnotí vhodnost vybraného empirického vztahu I.G.Goryachevy pro adhezivní opotřebení jako primárního mechanismu opotřebení a variuje koeficienty pro výzkum využití rovnice. Na data jsou aplikovány algoritmy strojového učení a je prezentována architektura nejlepšího modelu – Support Vector Regression – spolu s metrikami, analýzou důležitosti vlastností (feature importance) a optimálním rozdělení datasetu pro trénink a testování. Závěrem práce doporučuje směry dalšího výzkumu a způsoby, jak zlepšit proces modelování pro tento konkrétní problém.
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Determination of anodizing parameters for surface properties of aluminum alloys
Paclík, Eduard ; Vaverka, Ondřej (referee) ; Košťál, David (advisor)
The bachelor's thesis deals with the determination of basic parameters for anodizing aluminum alloys. The introductory passages include an overview of aluminum alloys suitable for anodization, theoretical and practical assumptions of anodic oxidation. The main experimental part discusses the laboratory anodic oxidation of aluminum alloy samples under different parameters of surface roughness, current density, and voltage. Anodically oxidized samples were tested on special UMT tribometer and Contour GT-X profilometer devices for friction coefficient measurement and surface inspection. The measurement results were used to determine the dependence between surface roughness of aluminum alloys and the quality of the anodized layer, the dependence between current density of the anodic process and the quality of the anodized layer, and the dependence between voltage and the quality of the anodized layer. The problem was solved within the possibilities of FSI laboratory conditions. The thesis serves as a basic orientation in this field.
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Untersuchung von Strukturen und Beschichtungen für tribologisch optimierte Umformwerkzeugoberflächen für die Aluminiumfeinblechbearbeitung
Kořenek, Jakub ; Hänel, Thomas (referee) ; Blecha, Petr (advisor)
V rámci bakalářské práce je provedena rešerše ke stavu techniky z pohledu tribologie, tváření hliníku, povlakování, strukturování a v závěru rozdělení tribologických zkoušek a metod jejich hodnocení. V praktické části jsou vyhodnoceny už dříve provedené pokusy na oscilačním tribometru. Následně byly provedeny pokusy tažení pásu s ohybem a bez ohybu s různými parametry pro jednotlivé zkoušky. Testovány byly různé laserové struktury (křížové, liniové, bodové) s variací jejich hloubky a pokrytí vzorků. V závěru práce jsou výsledky pokusů zhodnoceny z pohledu opotřebení, koeficientu tření a stability tribologického systému v průběhu pokusu. Z výsledků vychází doporučení pro následující pokusy a možné oblasti aplikace jednotlivých struktur.
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Plant oils for industry
Beran, Vojtěch ; Ficza, Ildikó (referee) ; Frýza, Josef (advisor)
This bachelor thesis describes usability of plant oils as liquid greases. The beginning of thesis follow up tribology problems and process of lubrication. The main section describes plant oils from perspective of their chemical composition and its closely related properties. In this thesis, plant oils are compared with another common liquid oils together with the comparison of its properties on specific application. In the conclusion, the thesis deals with summary of plant oils issues and with prospects for the future.
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Design of surface texturing experimental rig
Bouma, Adam ; Svoboda, Petr (referee) ; Šamánek, Otakar (advisor)
The aim of this thesis is mechanical indenter design, mainly two basic parts of this apparatus. The introductory section describes the basic techniques of mechanical surface texturing of engineering surfaces. The second part deals with the particular design of the device. It also describes the strength control of loaded components. The economic evaluation is given at the end.
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The effect of proteins on friction of artificial articular cartilage
Plachý, Tomáš ; Nečas, David (referee) ; Rebenda, David (advisor)
This bachelor thesis deals with the influence of the composition of synovial fluid on the coefficient of friction of artificial cartilage. The effect of protein concentration and their combination with other components of synovial fluid on the coefficient of friction of CD hydrogels simulating artificial cartilage is observed. All experiments were performed at a constant load of 10 N, speed 10 mm / s, temperature 37 ° C. In experiments investigating the effect of a combination of hyaluronic acid and phospholipids together with proteins, concentrations corresponding to a healthy individual were used. In experiments where the effect of the proteins themselves and their own combinations was investigated, concentrations corresponding to both a healthy individual and patients with advanced osteoarthritis or patients with aseptic release of the prosthesis were used. The work shows that when using the proteins alone, or their combination, there is a decrease in concentration of friction coefficient with increasing concentration. However, if hyaluronic acid alone or phospholipids alone is added to the protein, the coefficient of friction increases. The reduction occurs only after the addition of the combination of acid and phospholipid.
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Suitable lubricants for deep drawing of stainless steel
Mück, Jonáš ; Staněk, Vojtěch (referee) ; Lidmila, Zdeněk (advisor)
The intention of this thesis is the experimental evaluation of different lubricants and their suitability for deep drawing of stainless steel 1.4404. The testing method is based on the friction model at the point of drawing edge and retainers. This model corresponds with a structure of testing fixture. The suitability of every single lubricant for this application has been determined by comparison of the output, which is dependance of the strength on the track with the reference results. The testing has been performed on many different samples provided by various manufacturers. The best result was measured with the oil Kalorex AT 650 S, manufactured by AT Oil, which belongs to the group of environmentally harmful lubricants. Based on the results of this experiment we can conclude that chlorine content significantly increases the lubrication capability especially under high pressure. The modification of preparation geometry which presumes the elimination of certain undesirable disturbances accompnaying the experiemnt has been also proposed.
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Friction components produced by rapid prototyping
Pečenka, Tomáš ; Škaroupka, David (referee) ; Omasta, Milan (advisor)
The main aim of this bachelor thesis is to make an overview of use of additive technology for production of friction components. The first part is concerned on review of additive methods and type of materials. In the second section are situated applications of this technology for fabrication of friction components. The main goal of last part is research in area of tribology of parts manufactured by additive technology.
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