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.
Browse
Search Results
- Design and fabrication of bioreactors for tissue engineering(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2020-06) González Abrego, Ana Valeria; Rodríguez González, Ciro A.; lagdtorre/tolmquevedo; Martínez López, José Israel; Trujillo de Santiago, Grissel; Moisés Álvarez, Mario; School of Engineering and Sciences; Campus Monterrey; Dean, DavidTissue engineering (TE) has provided new techniques to create better tissue models, for study or to solve actual medical problems. Combining TE with design and 3D manufacture techniques can achieve devices that improve actual models. 3D tissue models present a diffusion problem that causes cell death because of the lack of oxygen and nutrients and the concentration of cell waste. Proving flow to the constructs can facilitate perfusion and enhance tissue. To do so, this document presents the designs and prototype development of two bioreactors, with the objective of diminishing necrotic core to create relevant implantable bone tissue and a more realistic breast cancer model. Using DLP and commercially available parts, designs were prototyped and validated.
- The Effects of Roller Burnishing Parameters Upon Surface Properties of AISI 52100 Bearing Steel (60HRC). A Finite Element Analysis -Edición Única(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2005-12-01) Jasso Lucio, Francisco; Rodríguez González, Ciro A.; Elías Zúñiga, Alex; Cortés Ramírez, Jorge A.; ITESM-Campus Monterrey; Viramontes Brown, Federico ÁngelThis thesis is based on the technical report HPM/ERC/NSM-05-R39 which was written in collaboration with the Engineering Research Center for Net Shape Manufacturing (ERC/NSM) [Jasso et. al, 2005a]. The author of this thesis spent some time on a research stance working at The Ohio State University in a roller burnishing project. Most part of the work presented in this document was conducted during that time. Hard roller burnishing is a cost effective surface finishing/enhancement process where a hard ball rolls on the machined surface under a high pressure and flattens the roughness peaks. Particularly when combined with hard turning, this process is able to provide a good alternative to abrasion-based finishing methods such as grinding operations. In this study, two main tasks were conducted, including 1) modifications of FEM modeling of roller burnishing from Yen’s model [Yen, 2004] and 2) FEM simulations to analyze the effect of roller burnishing parameters by using real process conditions selected from experiments previously conducted by the ERC/NSM) [Sartkulvanich, 2004b]. Specifically, the contents of each chapter of this thesis can be summarized as follows. Chapter 1 provides an introduction, which includes the description of roller burnishing process, advantages and challenges encountered in the use of roller burnishing to replace grinding. Overall and specific objectives are discussed in Chapter 2. Chapter 3 provides a literature review on roller burnishing research. It is mainly divided into three major topics, i.e. experimental study on the surface improvement by roller burnishing process, experimental study on the effect of burnishing process parameters, and modeling of roller burnishing. iii SUMMARY Chapter 4 summarizes the details of hard turning and roller burnishing experiments, conducted by the ERC/NSM. Information of experimental procedure and experimental data are given in this chapter. In addition to the data presented in [Sartkulvanich, 2004b], data from experimental measurements of residual stresses on hard turned and burnished AISI 52100 surfaces (obtained by X-ray diffraction technique) are also provided in this chapter. Chapter 5 presents the modifications made for the previously developed FEM model of roller burnishing in [Yen, 2004]. These include consideration of flow stress models from ball indentation tests, consideration of pressure loss during roller burnishing operation, selection of a workpiece size for the FEM model, determination of maximum ball penetration depth during roller burnishing, and evaluation of tool movement control in the 2D FEM model proposed by [Yen, 2004]. Chapter 6 discusses the FEM predicted results on the effects of the burnishing feeds and burnishing pressures upon surface properties. The predictions of surface finish and residual stresses are the focus of this analysis. FEM results were also compared with experimental data for validation. In summary, hard roller burnishing shows two main improvements on burnished workpieces: surface roughness reduction, and increase in compressive residual stresses beneath the surface. The effect of burnishing pressure is the most significant. Higher burnishing pressure produced smoother surface and more compressive residuals stress. Smaller burnishing feed provides similar surface improvements but to a less degree. Quantitatively, FEM results match well with the experiments for the residual stresses but not with the surface roughness parameters. Chapter 7 presents the author’s personal contributions, the findings of this study, some suggestions for further research on hard turning and roller burnishing as well as the application perspectives for this processes’ combination by the Mexican Industry.
- Surface Roughness Monitoring and Prediction in a High Speed end Milling Process in Aluminum and Steel Alloys-Edición Única(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2005-12-01) Villaseñor González, David Fernando; Rodríguez González, Ciro A.; Allque López, José Ramón; Ahuett Garza, Horacio; Morales Menéndez, Rubén; ITESM-Campus Monterrey; Viramontes Brown, Federico Ángel; Viramontes Brown, Federico ÁngelThe present study seeks to monitor and predict surface roughness in a high speed end milling process. Five specific objectives are sought in this study: 1. Establish a technological platform in which process monitoring is possible at high frequency sampling. 2. Analyze and predict the forced vibrations (Acc[x]) produced by the spindle speed and cutting conditions. 3. Determine the effect that the controllable parameters (spindle speed, depth of cut, feed per tooth and feed rate) together with forced vibrations have on the final Surface roughness (Ra). 4. Analyze and predict the machine vibrations (Acc[x]) produced by the spindle speed and its proper feed rate (Vf). 5. Create efficient surface roughness predictors for (7075-T6, 6061- T6 Aluminum and 1045 Steel) different materials in high speed end milling operations, using statistical analysis tools. 6. Compare theorical and estimated surface roughness models. Accelerometers and CNC variables are tested to experimentally acquire data of the machining process in order to develop a model in which the surface roughness of parts is predicted. Process parameters and dynamic vibrations are used to develop the model using regression statistical tools. While experimenting, tool diameter, parts material, and depth of cut are remained constant. Once the model is obtained, final experimentation is made to corroborate its reliability. Finally, a concluding study is made to determine the individual effect of each parameter with the surface roughness. IV TABLE OF CON
- Evaluation of CNC Controllers in Milling Machines-Relationship Between Dynamic Capability, Productivity and Cost-Edición Única(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2005-12-01) Reyes Luna, Fernando David; Rodríguez González, Ciro A.; Ahuett Garza, Horacio; Hendrich Troeglen, Nicolás; ITESM-Campus MonterreyCNC controllers play a key role in the selection and configuration of a specific milling machine tool. CNC controller technologies understanding and evaluation is important in order to take reliable decisions for a required application selection or configuration. This thesis presents a structured methodology for evaluating CNC controllers in terms of dynamic capability, productivity, and a relative cost valué for different performance indexes. Performance evaluation procedures are presented to quantify different performance indexes for CNC technologies or CNC controllers characteristics based on dynamic measurements. A qualitative scheme for different machine tool taxonomies associated with each CNC technology is classified for three markets to establish a technology cost reference. Experimental results using the proposed methodology are presented for two case studies.
- Impacto del fresado en duro y de la electroerosión por hilo sobre la microestructura superficial del acero D2 para la fabricación de insertos rectos(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2003-12-01) Amado Moranchel, Nicolás; Rodríguez González, Ciro A.; Hendrics Troeglen, Nicolás; Cortés Ramírez, Jorge A.; Programa de Graduados en Ingeniería; División de Ingeniería y Arquitectura; Campus MonterreyEl maquinado de materiales duros es un tema de gran interés hoy en día para la producción industrial debido al potencial de reducir operaciones, tiempos y costos de fabricación. Este trabajo presenta un análisis del impacto del fresado en duro y la electroerosión por hilo sobre la microestructura superficial en acero D2, con durezas de 58 a 60 HRC, para la fabricación de insertos rectos. Dichos insertos son representativos de las geometrías de las cuchillas de corte de dados. El maquinado en duro de las probetas se realizó en un centro de maquinado de alto desempeño, HURÓN KX-10, con herramientas planas enterizas de carburo de tungsteno micrograno y recubrimiento PVD MEGA. Se analizaron condiciones de velocidad de corte de 90 y 150 m/min (con dos niveles de desgaste para cada velocidad de corte). El maquinado de electroerosión por hilo se realizó en una máquina CHARMILLES ROBOFILL 300. El impacto de los procesos de maquinado sobre el material D2 se estudia en términos de desgaste de herramienta, metalografía, topografía y microdureza, además de estimaciones de temperaturas en el proceso de corte. Se analizó el desgaste de herramienta por medio de un microscopio óptico, mostrando un desgaste uniforme en el filo de la herramienta de corte. Al estimar las temperaturas de maquinado mediante el modelo de Boothroyd, se concluye que el proceso de fresado no provoca cambios de microestructura. El efecto ocasionado por los procesos de maquinado sobre la microestructura de la parte maquinada fue analizado con un microscopio óptico, observando una zona afectada dentro del rango de 2 a 4 j^m de profundidad. Las pruebas de topografía, realizadas en un microscopio electrónico de barrido, muestran cualitativamente un cambio de dureza en la superficie maquinada y deformación plástica. Sin embargo, las pruebas de microdureza indican un aumento poco significativo entre la zona superficial y el material base de estudio. Este estudio concluye que el proceso de fresado en duro y electroerosión por hilo provocan una zona de alteración poco significativa en la microestructura superficial del acero D2, comparada con la zona afectada que se observa en los procesos de torneado en duro y electroerosión por penetración respectivamente.
- Predicción de tiempo de ciclo en operaciones de fresado de alta velocidad-modelo mecanístico para acabado de superficies esculpidas(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2003-08-01) Siller Carrillo, Héctor Rafael; Siller Carrillo, Héctor Rafael; 223727; Rodríguez González, Ciro A.; Viramontes Brown, Federico; Ahuett Garza, Horacio; Vázquez Lasso, Víctor Hiram; Programa de Graduados en Ingeniería; División de Ingeniería y Arquitectura; Campus MonterreyEste trabajo estudia el impacto de la complejidad de la geometría en el tiempo de ciclo del fresado de alta velocidad de superficies esculpidas. Los experimentos realizados se enfocaron en superficies de referencia cuyo grado y cuya distribución de complejidad se modificaron de manera paramétrica. Los programas de control numérico para el fresado de dichas superficies se ejecutaron en un centro de maquinado HURÓN con controlador SIEMENS 840D a diferentes velocidades de avance programadas, cuantificando la discrepancia entre éstas y las velocidades de avance reales promedio. Se propone, con base en dichos experimentos y en un caso de aplicación, un modelo mecanístico para la estimación aproximada del tiempo de ciclo de operaciones de fresado de alta velocidad para el acabado de superficies esculpidas, considerando la dinámica del movimiento. Dicho modelo utiliza a) el histograma de distribución de longitudes de segmento en el programa de control numérico, basado en interpolaciones lineales y b) una caracterización de la máquina herramienta para movimientos con cambios bruscos y movimientos con cambios suaves de dirección. Se estudiaron dos familias de partes en las cuales se midieron discrepancias de 300 a 800% al comparar el tiempo de ciclo real vs. el tiempo de ciclo ideal, para una velocidad de avance programada de 16 m/min. Al aplicar el modelo propuesto es posible hacer una predicción del tiempo real de ciclo con un error máximo del 22%.
- Metodología para la evaluación integral de manufacturabilidad y desempeño funcional en partes inyectadas de termoplástico(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2002-05-01) Talavera Basave, Jesús; Rodríguez González, Ciro A.; tolmquevedo; ITESM-Campus Monterrey