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The development of glass substrates for use as an alternative to printed circuit boards (PCBs) attracts significant industrial attention, because of the potential for low cost but high performance interconnects and optical connection. Electroless plating is currently used to deposit conductive tracks on glass substrates and the quality of copper / glass adhesion is a key functional issue. Without adequate adhesive strength the copper plating will prematurely fail. Existing studies have covered the relationship between surface roughness and adhesion performance, but few of them have considered the detail of surface topography in any depth. This research is specifically considering the mechanical contribution of the glass surface texture to the copper / glass adhesive bond, and attempting to isolate new ISO 25178 areal surface texture parameters that can describe these surfaces. Excimer laser machining has been developed and used to create a range of micro pattern structured surfaces on CMG glass substrates. Excimer mask dimensions and laser operation parameters have been varied and optimized according to surface topography and adhesion performance of the samples. Non-contact surface measurement equipment (Zygo NewView 5000 coherence scanning interferometry) has been utilized to measure and parameterize (ISO 25178) the surface texture of the glass substrates before electroless copper metallization. Copper adhesion quality has been tested using quantitative scratch testing techniques, providing an identification of the critical load of failure for different plated substrates. This research is establishing the statistical quality of correlation between the critical load values and the associated areal parameters. In this thesis, the optimal laser processing parameter settings for CMG glass substrate machining and the topographic images of structured surfaces for achieving strong copper / glass plating adhesion are identified. The experimental relationships between critical load and areal surface parameters, as well as the discussions of a theoretical approach are presented. It is more significant to consider Sq, Sdq, Sdr, Sxp, Vv, Vmc and Vvc to describe glass substrate surface topography and the recommended data value ranges for each parameter have been identified to predict copper / plating adhesion performance.

Neste trabalho foram conduzidos experimentos de laboratório no intuito de avaliar o efeito da textura superficial no desempenho de óleos lubrificantes aditivados e não aditivados. Os materiais envolvidos nos ensaios são referentes a materiais de anel e camisa de motores de combustão interna e as condições de superfície envolveram processamentos de lixamento e retífica, bem como texturização de microcavidades a laser. Os ensaios foram do tipo alternado, com regime limítrofe de lubrificação. Inicialmente foram feitas análises sobre a metodologia utilizada para o cálculo do coeficiente de atrito em ensaios alternados, mostrando que os valores fornecidos diretamente pelo equipamento (aqui chamados de coeficiente de atrito pico a pico) não foram efetivos para este estudo, pois apresentam alta dispersão entre as réplicas dos ensaios e não é representativo em termos de eficiência do tribossistema. Foram geradas microcavidades nas superfícies de alguns blocos de ferro-fundido mediante texturização a laser. Esta texturização gerou rebarbas que foram retiradas por um processo de lixamento. Com isso, uma parte dos resultados avaliou o efeito do lixamento nos parâmetros de rugosidade, no entanto que o processo acaba por aumentar os valores de raio de aspereza e reduzir a altura média dos picos. Por fim, ensaios com óleo sem aditivo tiveram formação de óxido em todas as condições de superfície, com pouca variação do coeficiente de atrito. Já nos ensaios com óleo aditivado, os resultados mostraram pouca influência das microcavidades e maior contribuição das características de picos (raio e altura) na formação de tribofilmes redutores de atrito (neste caso MoS2). / This work was conducted by experimental tests in order to evaluate the effect of surface texture on fully formulated oil and base-oil performance. In these tests, the materials were related to the piston ring and cylinder, in which surfaces were sanded, grounded and textured by laser. In addition, the tests were carried out by reciprocating movement and boundary conditions. A coefficient of friction study in reciprocating tests was performed, showing that peak-to-peak methodology does not represent properly the tribosystem efficiency. Burr was generated around the dimples (made by laser surface texturing), in which were removed by sanded process. The results showed that sanded process increased the peak radius and decreased the peak height. The results considering the base oil showed oxide formation on the surface in all the cases, occurring low variation of friction coefficient in the system. On the other hand, in the fully formulated oil results, the dimples had no influence on MoS2 formation; however, it was possible to see a strong relation with the radius and average height of the asperities.

Perception and sense of touch are extremely important factors in design, but until recently, the exploration of skin tribology related to tactility has been relatively untouched. In this emergence, skin-on-polymer interactions are becoming more widely investigated due to the prevalence of polymers in everyday life, and the ability to define these interactions in terms of tactility would be hugely beneficial to the engineering and design process. Previous work has investigated polymer textiles concerning tactility, examining environmental and material properties that affect skin on fabric coefficient of friction. In this study, similar friction procedure was used to compare coefficients of friction of a fingerpad across varying polymer fabrics. Forces were applied in both longitudinal and lateral directions, and it was discovered that force directionality greatly affects coefficient of friction. Specific causes have yet to be determined, but it is suspected that material weave and microscopic surface properties play a major role in this directional behavior. To complement these studies and relate them to tactility, trained human evaluators rated the samples against four tactile attributes: abrasiveness, slipperiness, sensible texture, and fuzziness. These ballots were then analyzed with Quantitative Data Analysis and shown to be repeatable among the participants, and each of the attributes were shown to be statistically independent of coefficient of friction. It should be noted, however, that fuzziness showed the greatest correlation coefficient of R^2=0.27. Material selection plays an integral role in frictional behavior, and researchers have been studying contact theory on both microscopic and macroscopic levels to determine how surface topography affects skin-polymer tribology. To negate material effects discussed in the Greenwood-Williamson contact model, frictional tests were performed on identical polypropylene plaques with textured grooves of varying dimensions. Both geometry and directionality proved to be major frictional contributors; as groove size increased, finger friction in the longitudinal direction decreased, but friction increased laterally. In addition to testing a fingerpad, friction was measured with a silicone wand to simulate a finger with different material properties. The silicone exhibited the opposite trend as skin; as groove width decreased, frictional forces increased longitudinally and decreased laterally. While topography affects frictional behavior, counterface stiffness, and intrinsic material properties may cause the trend shift between skin and silicone.

Surface roughness is an important parameter in the automotive Industry. This thesis is a study conducted in collaboration with QSO Interferometer systems AB (QSAB), Halmstad. The study is focused on the existing surface roughness parameters used in the automotive industry and the relationship to the CWS parameters of QISAB. The study also investigates the scope of CWS instrument developed by QISAB as a next-generation automated surface testing inline instrument. The initial study which has been conducted had 5 stages, those are the history of roughness measurement, the basic CWS parameters, the currently used surface testing instruments in the automobile industry, the use of surface metrology in the manufacturing industry and the basic principle and theory of the CWS. As the final stage to achieve the aim of the thesis a quantitative study has been conducted to compare the existing parameters with CWS parameters. The three type of comparison were done on a test piece having different range of surface roughness after different stages of grinding. These three comparisons that had been done were CWS v/s White light interferometer v/s visual inspection. The results from those quantitative analysis did support the results from the qualitative analysis.

Neste trabalho foram conduzidos experimentos de laboratório no intuito de avaliar o efeito da textura superficial no desempenho de óleos lubrificantes aditivados e não aditivados. Os materiais envolvidos nos ensaios são referentes a materiais de anel e camisa de motores de combustão interna e as condições de superfície envolveram processamentos de lixamento e retífica, bem como texturização de microcavidades a laser. Os ensaios foram do tipo alternado, com regime limítrofe de lubrificação. Inicialmente foram feitas análises sobre a metodologia utilizada para o cálculo do coeficiente de atrito em ensaios alternados, mostrando que os valores fornecidos diretamente pelo equipamento (aqui chamados de coeficiente de atrito pico a pico) não foram efetivos para este estudo, pois apresentam alta dispersão entre as réplicas dos ensaios e não é representativo em termos de eficiência do tribossistema. Foram geradas microcavidades nas superfícies de alguns blocos de ferro-fundido mediante texturização a laser. Esta texturização gerou rebarbas que foram retiradas por um processo de lixamento. Com isso, uma parte dos resultados avaliou o efeito do lixamento nos parâmetros de rugosidade, no entanto que o processo acaba por aumentar os valores de raio de aspereza e reduzir a altura média dos picos. Por fim, ensaios com óleo sem aditivo tiveram formação de óxido em todas as condições de superfície, com pouca variação do coeficiente de atrito. Já nos ensaios com óleo aditivado, os resultados mostraram pouca influência das microcavidades e maior contribuição das características de picos (raio e altura) na formação de tribofilmes redutores de atrito (neste caso MoS2). / This work was conducted by experimental tests in order to evaluate the effect of surface texture on fully formulated oil and base-oil performance. In these tests, the materials were related to the piston ring and cylinder, in which surfaces were sanded, grounded and textured by laser. In addition, the tests were carried out by reciprocating movement and boundary conditions. A coefficient of friction study in reciprocating tests was performed, showing that peak-to-peak methodology does not represent properly the tribosystem efficiency. Burr was generated around the dimples (made by laser surface texturing), in which were removed by sanded process. The results showed that sanded process increased the peak radius and decreased the peak height. The results considering the base oil showed oxide formation on the surface in all the cases, occurring low variation of friction coefficient in the system. On the other hand, in the fully formulated oil results, the dimples had no influence on MoS2 formation; however, it was possible to see a strong relation with the radius and average height of the asperities.

This master´s thesis deals with calibration and determination of uncertainties of measurement for focus variation microscope Alicona Infinite Focus G4. Together with calibration, a measurement of chosen parameters with calculation of measurement uncertainties of a component was realised. The thesis also describes the whole calibration process and terminology used in calibration, as well as the calibrated instrument, it´s parameters and usage in practice. The measurements were realized on premises of Intemac Solutions s.r.o. Obtained data were than processed using MS Excel, Gwyddion and TalyMap software. At the end of the thesis, practical recommendations are formulated.

Thesis solves the problem of influence of variable process conditions during grinding on surface texture parameters, provides precision of measurement methods, assessed by laser interferometry measurement methods and piezoelectric measurement of vibration of technological equipment and processes using statistical methods the correlation between the amplitude of oscillation and on surface texture parameters. Further it provides the prediction of the impact of input parameters to the output parameters of the technological process for a long-term perspective.

No description available.