Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Finite element simulation of the mechanical performance of a WE43 magnesium‐alloy biliary stent(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2023) Serrato Lara, Diana Laura; Vázquez Lepe, Elisa Virginia; emipsanchez; Rodríguez González, Ciro Angel; García López, Erika; Escuela de Ciencias e Ingeniería; Campus Monterrey; Pérez Santiago, RogelioThis thesis presents a research endeavor focused on designing a biliary stent to address complications arising from laparoscopic cholecystectomy, with a specific emphasis on bile duct injuries. This work emphasizes the development of a biodegradable magnesium-based alloy stent (WE43). Using the finite element method (FEM), this study aims to simulate the mechanical behavior of the WE43 magnesium alloy biliary stent through non-clinical tests, including a three-point bending test and balloon expansion. Critical to this simulation is the validation process, a material characterization of the WE43 magnesium alloy and a meticulous analysis of the stent's mechanical properties under varied boundary conditions is performed. The research proposes a stage gate process for the development of the biodegradable biliary stent and introduces a methodology for the characterization of the WE43 magnesium alloy, improving the accuracy of experimental predictions. The outcomes demonstrate the efficacy of the Finite Element Method in predicting stent deformation under diverse physiological conditions, particularly in three-point bending and balloon expansion tests.
- Influence of process parameters on surface topography of nitinol manufactured by fiber laser cutting for medical applications(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2021-12-09) Cadena Calvillo, Mariana; VAZQUEZ LEPE, ELISA VIRGINIA; 268852; Vázquez Lepe, Elisa Virginia; puelquio/mscuervo; Rodríguez González, Ciro Ángel; López Botello, Omar Eduardo; School of Engineering and Sciences; Campus Monterrey; García López, ErikaThe need and tendency to develop medical devices on the micron scale has created an opportunity to micro cutting processes that have the capability of manufacturing quality medical devices. Thereby, the necessity of materials that have unique features to improve the deliverability and the performance of these devices have made nitinol one of the most selected materials for this industry. Nevertheless, the study of the micro processing of nitinol tube for the application on medical devices, through fiber laser cutting and its response to surface quality has not been thoroughly researched. Hence, in this research the response of fiber laser cutting parameters, such as spot overlapping and pulse energy, on Ni-Ti alloy (nitinol) was statistically analyzed through surface quality through average surface roughness, and heat-affected zone. Results showed that spot overlap had most impact on surface quality, since surface roughness decreased increasing spot overlap, but further increase resulted on increased surface. Minimum surface roughness of 1.482 µm, with 83.72% of spot overlap and 72.16 of pulse energy. Presence of HAZ, and dross found on highest values of spot overlap and pulse energy. In conclusion, fiber laser cutting has the capability to produce high surface quality nitinol self-expanding stents.
- Design and fabrication of transdermal microneedle inserts by Stereolithography for Ultrasonic Injection Molding(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2020-12-08) Villa Carrillo, Karla Marcela; Vázquez Lepe, Elisa Virginia; tolmquevedo; García López, Erika; Rodríguez González, Ciro Angel; School of Engineering and Sciences; Campus Monterrey; Martínez López, José IsraelIn this work design of a transdermal microneedle patches with hexagonal and squared cross-sections are explored using stereolithography for manufacturing ultrasonic injection molding inserts. A multi-cavity mold was designed using Finite Element Method based software, where polypropylene injection molding simulations were performed for design optimization. Manufacture of the proposed device was assessed using a stereolithography based additive manufacturing equipment suitable for high temperature applications. Dimensional accuracy was evaluated using three-dimensional metrology. Deviational height errors of 18.05% and 39.21% were found for the hexagonal and square microneedle insert cavities. A successful proof-of-concept ultrasonic injection molding is a step forward for manufacturing of microneedles for the point-of-care.
- Evaluation of the dimensional capabilities for the technologies of selective laser melting and digital light processing, to fabricate microcavities: microneedle insert as case of study.(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2020-06-16) Meneses Ricaurte, Cindy Paola; Vázquez Lepe, Elisa Virginia; emipsanchez/tolmquevedo; Sandoval Robles, Jesús Alejandro; Rodríguez González, Ciro Ángel; School of Engineering and Sciences; Campus Monterrey; García López, ErikaAdditive manufacturing technologies are nowadays a feasible resource in micro parts fabrication, which have a wide range of applications from medical industry to injection molding. These technologies allow fabrication of complex parts with a variety of geometries and sizes that ultimately gives a competitive advantage by letting the manufacturing of insert molds. This research study the dimensional capabilities of selective laser melting and digital light processing to produce microneedle cavities from 500 μm to 2500 μm. An insert for microneedle was manufactured variating its bases geometries and successfully fabricated through selective laser melting at 0°, 45° and 90° orientations. Similarly, for the digital light processing technology, inserts for microneedle geometries were manufactured at 0° and 45° build surface orientation. It was found for the hexagonal base geometry, the best for both technologies with the lower dimensional errors, due to a common factor between processes called stair steeping. By using a reduction in border and contour power, height dimensional accuracy of the microneedle insert was improved. There was a minimum error of 3% for 600 μm of nominal height corresponding to the fabricated insert by selective laser melting at 0°orientation of construction with the optimal design.
- Manufacturability of PLA parts reinforced with TiO2 nanoparticles by ultrasonic molding.(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2020-06-16) Macías Naranjo, Mariana; VAZQUEZ LEPE, ELISA VIRGINIA; 268852; Vázquez Lepe, Elisa Virginia; mla, emipsanchez; Ortega Lara, Wendy de Lourdes; Rodríguez González, Ciro Angel; School of Engineering and Sciences; Campus Monterrey; Ferrer Real, InésThe objective of the thesis is to define and to validate a methodology for the stabilization of process parameters in ultrasonic molding and to analyze the manufacturability of PLA parts reinforced with TiO2 nanoparticles in the ultrasonic molding process. Ultrasonic molding is a new technology used for micro-part molding, reducing the necessary energy, process times, and material waste. Validating a methodology for this process, PLA was processed with TiO2 nanoparticles to observe the response of the process in this combination of materials. In addition, to observe the influence of the concentration of nanoparticles by performing the characterization to find an application in the medical sector in the future.
- Micro machinability of net shapes of Selective Laser Melting of Ti-6Al-4V for minimum material removal using ball end mill(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2018-05-15) Celis Renata, Pavel; Vázquez Lepe, Elisa Virginia; García López, Erika; Rodríguez González, Ciro Ángel; Sandoval Robles, Jesús A.Miniaturization of medical devices is playing an important role in the manufacture industry. New drug delivery systems are being studied and developed, therefore materials to produce these devices must be investigated extensively. The objective of this work is to experimentally investigate and compare the machinability of Ti-6Al-4V titanium alloy produced via Selective laser melting (SLM) against the conventional machining method. 18 patches of 09 needles each were fabricated and machined with different cutting feeds (120,150 and 180mm/min) with aid of a minimum quantity lubrication (MQL) system. Machinability was examined in terms of cutting forces, tool wear, surface roughness and geometrical dimensions. Each cutting feed was tested by fabricating 3 patches from solid blocks of titanium with square tools of .8mm. Finish pass was performed with a .2mm micro ball end mill with a constant spiral toolpath. Comparison was performed by fabricating four patches with SLM with an excess material of 150μm and machined with the same previous parameters. 3D images obtained by optical microscope reveal that the main force applied in the finishing of needles is the Z axis and cutting forces were higher when machining SLM patches. Tool calibration is the main factor to obtain high precision in geometrical dimensions due to the variation in length because of thermal expansion. Surface roughness for all tests were below 1μm with best results when cutting feed is set at 120mm/min, reduction in edge radius for ball end mills affected negatively the surface roughness. An economic comparison was performed and showed that the SLM combined with SM process has clear advantage over subtractive manufacture alone.
- Design of a Bioabsorbable stent as preventive treatment of complication in bariatric surgery RYGBP(2017-12-05) Jara Mendiola, Juan Manuel; Vázquez Lepe, Elisa Virginia; García López, Erika; Rodríguez González, Ciro ÁngelA new approach to the treatment of complications of RYGBP is covered by the implementation of design methodologies as quality function deployment and theory of inventive problem solving, (QFD and TRIZ) to propose a Design of a bioabsrobable stent as a preventive treatment. In despite on the variability of documented results of degradation rates of bio polymers and bio metals, a new lab protocol is proposed to homogenize both families of materials degradation rates into comparable results. The usage of PLA and AZ31 into a new protocol proposal of degradation tests were carried on. The design resultant by the design methodologies were tested by finite element analysis to compare compression resistance, flexibility and compressibility. Three design proposals are shown with acceptable performance and an expected functional life time.
- Preparación de fibras híbridas de composito carbono-carbono(Instituto Tecnológico y de Estudios Superiores de Monterrey) González Dueñas, Victor Alejandro; Vázquez Lepe, Elisa Virginia; Campus MonterreyEl principal objetivo del presente trabajo es la preparación de un composito de carbono-carbono a base fibras de alcohol polivinílico (PVA) reforzadas por diferentes nanoestructuras de carbono mediante la técnica de forcespinning con el fin de mejorar su direccionalidad y obtener una morfología homogénea. Luego mediante un proceso de pirólisis se obtuvieron fibras de carbono, con el fin de obtener un material más atractivo al mejorar sus propiedades térmicas, eléctricas y mecánicas en aplicaciones de almacenamiento de energía. Los resultados más sobresalientes de este trabajo indican la innovación del equipo de forcespinning, al modificar la geometría del dispensador de polímero incrementando la capacidad de solución por prueba y eliminando el uso de agujas o sistemas de integración de jeringas mediante una perforación sobre la cara del dispensador que permite la deposición de las fibras en la superficie obteniendo direccionalidad, se analizaron distintas concentraciones en la solución de 5, 10, 15 y 20% w/v para determinar el parámetro de velocidad rotacional para obtener un mejor procesos de producción en comparación al equipo tradicional. Además, se observó que la incorporación de las diferentes nanoestructuras de carbono en concentraciones de 0.5% w/v - 1% w/v no modifican la viscosidad de la solución lo cual evita la modificación de parámetros del equipo. La espectroscopia infrarroja (FTIR) determino que no hay un cambio estructural en el polímero y la presencia de las nanoestructuras de carbono. La microscopía electrónica de barrido (SEM) confirmó la obtención de fibras con un diámetro final de <2.1 ± 0.3 μm para cualquiera de las diversas muestras, al se agrega cloruro de sodio (NaCl), hay una disminución en el diámetro de las fibras <1.8 ± 0.2 μm de tamaño, lo cual incrementa el área superficial del material Por voltametría cíclica (CV) se estudiaron las propiedades electroquímicas de los compositos obteniendo corrientes de 10-2 y 10-3 amperes al estabilizarse por tres semanas en el electrolito dichas corrientes son mayores a las de un capacitor de cerámico comercial por lo que mejoraría la capacidad de almacenamiento de energía en dispositivos electrónicos.