Metodología para caracterización de rugosidad superficial 3D

Abstract

El objetivo de esta tesis es establecer una metodología estructurada de medición de rugosidad superficial 3D de conformidad con los lineamientos de la nueva norma ISO 25178, considerando la utilización de distintos sistemas ópticos de precisión y que permita la comparación sistémica de métodos asociados a diversos principios físicos, así como la definición de lineamientos de selección y aplicación para los métodos considerados. Para tal fin se dispuso realizar un estudio comparativo, considerando parámetros metrológicos para la medición de la rugosidad 3D, en sistemas de medición de microscopia confocal e interferometría de luz blanca, con el propósito de estructurar protocolos para procesos de medición de la rugosidad 3D de conformidad con la norma ISO- 25178 en sistemas de medición con microscopio confocal y por interferometría de luz blanca. Los análisis realizados mostraron una importante influencia de parámetros pre y post proceso en las mediciones que no se creían representativos al inicio del estudio, de igual manera se entiende la importancia de controlar todas las variables dado que esto influye directamente en la incertidumbre de medida y más aún cuando se trata de escalas micro y nano, por otra es notable que Latinoamérica se encuentra en un estado dando sus primeros pasos en este campo pero se resalta su importancia para el desarrollo de la industria y la investigación de innumerables áreas tales como desgaste, lubricación y tribología, fatiga, sellado, unión y adhesión, eficiencia de componentes mecánicos, óptica y paneles solares, biología, química, bacteriología, optometría, ortopedia, fabricación avanzada, manufactura aditiva, ciencia de materiales, industria aeroespacial, automotriz, almacenamiento de datos, semiconductores, MEMS, pintura, recubrimientos, análisis de películas delgadas geología entre muchos más. El trabajo realizado se centró en la medición de los parámetros de rugosidad en los equipos WLI y LSCM en probetas de superficies mecanizadas comunes tales como torneado, fresado, rectificado, pulido, brillado, entre otras, de material cerámico y metálico

Abstract: The objective of this thesis is to establish a structured methodology for measuring surface roughness 3D in accordance with the new standards ISO 25178, considering the use of different optical systems of precision and allowing the systemic comparison of methods associated with various physical principles, As well as the definition of selection and application guidelines for the considered methods. To this end, a comparative study was carried out, considering metrological parameters for the measurement of 3D roughness, in confocal microscopy and white light interferometry measurement systems, with the purpose of structuring protocols for 3D roughness measurement processes according to with the ISO-25178 standard in confocal microscopy and white light interferometry. The analyzes performed showed an important influence of pre and post process parameters on the measurements that were not considered representative at the beginning of the study, as well as the importance of controlling all the variables since this directly influences measurement uncertainty and more Even when it comes to micro and Nano scales, on the other it is notable that Latin America is in a state taking its first steps in this field but its importance is emphasized for the industrial and investigative part as wear, lubrication and tribology, fatigue, sealing, bonding and adhesion, efficiency of mechanical components, optics and solar panels, biology, chemistry, bacteriology, optometry, orthopedics, advanced manufacturing, additive manufacturing, materials science, aerospace, automotive, data storage, semiconductors, MEMS, painting, coatings, thin film analysis geology among many more. The work carried out focused on the measurement of the roughness parameters in the WLI and LSCM equipment, in specimens with common machined surfaces such as turning, milling, grinding, polishing, shining, among others, of ceramic and metallic material (Titanium and Steel); subsequently, sinusoidal patterns were used. activities aimed at finding the solution to the non-convergence of the results between said devices, the influence of the objective, aperture diameter (Pinhole), transmitted light of the laser (Transmitted Light), sampling area, cutoff, type of filter in LSCM, the LSCM, WLI and the tactile method were compared considering ISO25178 and ISO4287. It was concluded that the convergence lies fundamentally in the selection of the filter and the cutoff value chosen, given that these determine the window of selection of the information to be evaluated, however, the pre-process parameters such as aperture diameter, laser transmitted light , area of sampling, objective (taking into account the reliability theory in LSCM), number of cutting planes, resolution of the image, are significant in the resolution of the instrument and in the quality of the information that is collected from the surface, Given that the smaller aperture diameter, the greater the transmitted light, the sampling area and the number of cutting planes, a better resolution is obtained, however, the selection of the lens brings with it a particularity, the greater the observation window is increased the smaller , which allows to see surfaces with small values of Rz (height of the peaks) in greater detail but limits the observation of surfaces that have values s high RSM (distance between peaks).