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Analysis of friction of hip joint replacements with modification of surface topography
Němeček, Daniel ; Quinn, Cheney (referee) ; Nečas, David (advisor)
Hip endoprosthesis introduces an effective treatment for patients suffering from advanced stages of hip degeneration. Despite the advancements made in recent years, limited longevity negatively affects the application of this technology in young patients. The main mechanism which causes limited longevity is wear, which depends on the friction and lubrication of the joint. This thesis aims to observe the effect of a textured surface on a UHMWPE polyethylene cup combined with a smooth femoral head as a solution, which may reduce the friction and wear of the contact surfaces. Two textured cups and three smooth femoral heads were used in the experiment (ceramic, metal, oxinium). The results showed that the textured surface has a positive effect on both reducing friction and providing more stability with the use of synovial fluid. A significant reduction in friction is observed for the surface with smaller dimples rather than for the surface with larger ones. Specifically, the combination of a ceramic femoral head and a finely dimpled surface resulted in the reduction of friction by 66 %. Attention was also paid to the effect of the load on the hip. In most cases, the load did not significantly impact the results. It can be assumed that reducing the friction at the joint leads to the reduction of the rate of wear, thus increasing the implant longevity.
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Utilization of surface texture evaluation in revolver production
Kolena, Robert ; Šrámek, Jan (referee) ; Jankových, Róbert (advisor)
This diploma thesis addresses the issue of using the evaluation of surface texture in the manufacture of revolver with aplication to a cock. It deals with the detection of imperfections of production operations, the proposal of corrective measures and its implementation. The use of new grinding wheel was chosen as a corrective measure. The Rzmax parameter was used to specify the surface texture after miling and a combination of the Rzmax and Rpmax parameters was used to specify surface texture after grinding.
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Advanced methods of surface topography evaluation
Šindelka, Marek ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
This thesis focuses on a measuring and topography of a components´ surface evaluation and it contains the overview of basic methods which includes the description of contact and non-contact measuring devices. Furthermore, the thesis also describes ways of surface texture evaluation through profiled and areal method, including an outline of ČSN ISO parameters. The practical part of the thesis focuses on the evaluation of metric threads´ M10 surface, crafted by diverse cutting and forming threads. The surface was scanned with the optical device called Alicona IFM G5 and it was evaluated through the profiled and areal method. The 2D and 3D parameters were acquired and then compared during the measuring.
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Advanced methods of surface topography evaluation
Toman, Ladislav ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
This paper deals with the description of the surface texture measurement methods, describes the devices by which the surface texture can be recorded and describes the parameters that allow the surface texture to be quantified. The practical part deals with the evaluation and comparison of the parameters of metric threads M10 made by cutting and forming by analysis of their cross-sections, then the attention is focused on the analysis of pressure forces and torques which occur during the manufacture and in the last part of the thesis there is an economic evaluation of the cost of manufacturing one piece of cut thread.
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Advanced methods of surface topography evaluation
Metelková, Jitka ; Prokop, Jaroslav (referee) ; Píška, Miroslav (advisor)
This paper provides an overview of contemporary methods for evaluation of the part surface, nowadays measurement devices and evaluated parameters. The main part of the paper is devoted to advanced methods of surface topography evaluations including the application of the new non-contact measurement technique Alicona G4. The experimental part deals mainly with a study of surface texture parameters of the machined aluminium alloy AlCu4MgSi when face turning. It concerns mostly a study of the tool feed rate influence (the uncoated insert GIPA-6.00-3.00, ISO 513 N05-N25, Iscar) on selected profile and surface parameters, including comparison of measurement results achieved by the contact (Form Talysurf Intra 50, Taylor Hobson) and non-contact method (IFM G4, Alicona).
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Calibration of Talysurf CCI coherence scanning interferometer
Varava, Anastasia ; Jankových, Róbert (referee) ; Harčarík, Matej (advisor)
This master’s thesis deals with calibration of a coherence scanning interferometer Talysurf CCI Lite. Basic terms related to surface texture evaluation were described along with selected profile and areal surface texture parameters. The working principle and design of the calibrated instrument were explained. Manufacturer’s calibration procedure was analyzed in relation to the definition of calibration in the International vocabulary of metrology. Further calibration steps leading to calculation of measurement uncertainty were presented. Last but not least, measurement uncertainties of areal surface texture parameters Sq and Sz were evaluated. The procedures and results described in this thesis may contribute to wider use of non-contact surface texture measuring instruments.
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Contact and non-contact method of surface texture evaluation
Harčarík, Matej ; Hammer, Miloš (referee) ; Jankových, Róbert (advisor)
The goal of this thesis was to create an overview of methods of surface texture evaluation, to analyse measurements of roughness profile parameters made with contact instruments and non-contact instrument Talysurf CCI Lite and to deduce practical recommendations from them. Based on measurements made, analyses of influence of cut-off settings on roughness measurement and of measurement variability were performed. Steps of the measurement process requiring special attention were identified. The output of this thesis is a proposal of measurement procedure for Talysurf CCI Lite.
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Measurement of Surface Texture Parameters of Products Using Contact and Non-contact Methods
Harčarík, Matej ; Hammer, Miloš (referee) ; Jankových, Róbert (advisor)
This master’s thesis includes an overview of profile method of surface texture evaluation according to ISO standards and VDA automotive standards, as well as an overview of areal method according to ISO 25178 standard series, which includes a proposal for improvement of czech terminology. Suitability of application of selected measurement methods for measurement of a portfolio of automotive parts was evaluated based on measurements carried out using a contact profiler, a coherence scanning interferometer and a confocal microscope. Further recommendations for practice in surface texture metrology were also formulated. A regression analysis of the relationship between values of selected profile surface texture parameters and their areal equivalents was also performed. Its results may aid the spread of areal surface texture evaluation in the industry.
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Advanced methods of surface topography evaluation
Hroděj, Daniel ; Osička, Karel (referee) ; Píška, Miroslav (advisor)
This paper deals with the analysis of data obtained from the surface of aluminum alloy 7475-T7351 after face milling with a tool inclination of 1°. The theoretical part explains the basic principles of measuring the topography of the surface and instruments that are able to provide relevant data directly from the scanned part. The following part contains the methods of evaluating the information, especially using various types of parameters acquired from ČSN EN ISO standards. The practical part focuses on the data obtained from the sample surface using the Alicona IF-G5. This information determines the character of the surface texture with the tool inclination and the difference between the profile and surface parameters. There is also described surface texture in the tool path and on the edge of the tool path. In the final economic evaluation, the connection between the feed per tooth and the machining price is found.
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