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Tecnología Cerámica – GITEC

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Sliding and corrosion wear of magnetron sputtered tio2 films deposited with different argon and oxygen mixtures

Aperador Chaparro, Willian | 2021-06-15

Were produced TiO2 thin coatings prepared, on substrates pure Titanium using a deposition by magnetron sputtering technique, the percentage of oxygen was varied, to study the behavior in terms of friction coefficient corrosive fluids such as those related to the human body. Electrochemical Impedance Spectroscopy (EIS), wear tests with a tribometer, were performed to obtain the tribo-corrosion mechanism of deterioration, taking into account the dual corrosion wear system. The phases were identified by X-ray Photoelectron Spectroscopy (XPS) high resolution. It is determined through the tests performed that the surface treatment has a different effect for each percentage of oxygen influenced by the simulated body environments. The wear performance analysis indicated that the TiO2 film's protection had increased as the percentage of oxygen in the gas mixture (Ar/O2) varied and other synthesis parameters such as deposition time, target power, and substrate temperature remained constant.

SYNERGISTIC CORROSION-WEAR EFFECT IN AUSTENITIC POWDER METALLURGICAL STEEL WITH DIFFERENT TITANIUM ADDITIONS

Aperador, w | 2022-01-01

To ascertain the influence of titanium percentage in 316L austenitic steel, titanium percentages varied from 0.5 to 2% aggregated to 316L steel. The powder metallurgy method was used. The powdered material was pressed at 800 MPa and then sintered at 1300°C. The X-ray diffraction (XRD) technique was used to characterize the identification of the phases after the processed mixtures. Wear and tribowear properties were determined by pin on disc tests. Electrochemical polarization curves were used to study corrosion. According to the results of the samples, the corrosion resistance of titanium increased to a percentage of 1.5% due to the formation of the phases generated by the mixture. However, it was determined that the most appropriate percentage is 2%, due to the synergistic mode specifically for wear and corrosion resistance, the mechanism is the most adequate.

Characterization of clay material and rice husk from northeast Colombia

Sanchez Molina, Jorge | 2021-01

This research was to study materials from the region to use them industrially applying the circular economy concept. Clay Material and Rice Husk were evaluated in the manufacture of ceramic products. X-ray Diffraction and X-ray Fluorescence techniques were used to determine the raw materials' chemical and mineralogical composition. Thermal analysis techniques (TG and DTG) were used to complement the study. The XRD results showed an abundance of quartz. The results of the thermal analysis establish significant losses due to calcination. The thermal conductivity was also measured in ceramic specimens made from two types of pastes, one with 100% Clay Material and the other with a 5% substitution for Rice Husk. The results showed a decrease in thermal conductivity in the test tubes with the addition of Rice Husk. Consequently, the Rice Husk as a substitute for the Clay Material allows for ceramic production with thermal efficiency.

Characteristics of refractory bricks used in the coke production kilns in Colombia

Gelves Diaz, John Freddy | 2021-06-04

A study has been carried out on the main physicochemical characteristics of the refractory bricks that are currently used in traditional coke-making kilns in Colombia. Two classes of material (brick) used in this industry were collected, which come from a geographical area of the country that supplies brick to many kiln builders. These materials were characterized by X-ray diffraction and fluorescence, scanning electron microscopy, dilatometry, thermal conductivity, pyroscopic resistance, and percentage of water absorption. The results obtained show that these materials have had very low firing temperatures in the factory, which is evidenced in the dilatometry, microscopy and water absorption percentage data. This characteristic brings with it high firing shrinkages when subjected to high temperatures (> 4% at 1,200 °C). There is a high presence of quartz in the material (40% or more), an aspect that increases the risk of fissure formation. Chemically there is a limited aluminum content (between 22% and 23%) compared to other reference refractories. The onset of fusion of these materials occurs around 1,360 °C. The thermal conductivity obtained can be considered moderate (between 0.634 W⁄mK and 0.760 W⁄mK), thus demonstrating limited applicability as an insulator.

Anticorrosive evaluation of copper-iron mixtures processed by powder metallurgy

Bautista-Ruiz, Jorge | 2021

Through the powder metallurgy process, copper and iron powders were mixed in the proportions Cu between 15% to 75% and iron from 25% to 85% that made up the binary material systems. Material systems were topographically characterized with atomic force microscopy. Corrosion tests were established using potentiodynamic polarization curves. The worn surfaces' characterization was carried out by means of a Confocal Scanning Laser Microscope to complement the study. It was determined that the mixtures' stability and behaviour have different behaviours depending on the evaluated system because the wear system caused, indicating that the phenomenon can be additive. The corrosive phenomenon is dominantly affected by the microstructure of the material. From the results found, it is possible to infer that the best systems evaluated by corrosive contain the highest percentage of copper content. The topographic variation indicates the transition from the active zone to the passive zone of the metal due to electrochemical reactions in the presence of aggressive media.

Wear synergy of copper-iron mixtures processed by powder metallurgy

Operador, W | 2021

Through the powder metallurgy process, copper and iron powders were mixed in the proportions Cu between 15% to 75% and iron from 25% to 85% that made up the binary material systems. The X-ray diffraction technique was used to determine the crystalline structure. Material systems were topographically characterized with optical microscopy. Tribology tests were established using a pin on the disk tribometer. It was determined that the stability of the mixture has different behaviors depending on the evaluated system because the wear system caused, indicating that the phenomenon can be additive. The mixed material is characterized by high friction coefficient and high wear due to the samples' specific properties by increasing the amount of iron in the mixture. The systems analyzed indicate that mechanical degradation was mainly reduced. Dimensional variation of the study specimens was evidenced due to the influence of copper in the system. Only the austenitic structure of the steel was observed, which indicates a complete diffusion of the copper.

Utilization of agro-industrial waste to improve thermal behavior of products made of fired clay for traditional masonry

Sanchez Molina, Jorge | 2021-08-09

The reutilization of agro-industrial waste in the manufacture of fired clay products is a sustainable strategy that aims at the circular economy. The most known waste in Norte de Santander, Colombia, are coffee husk and rice husk. For this reason, this research studies the thermal impact of their insulating properties in traditional masonry products made of fired clay to be considered as insulating additives. The methodology involves the simulation of heat transfer and heat flux of the multiperforated brick and H10 block manufactured in mixtures of 100% clay and 95% clay and 5% additive to wastes in North Santander, Colombia, in the software ANSYS under the finite element method in extreme conditions of San José de Cúcuta. The results demonstrate that the residues of rice husk and coffee husk act as insulating technological nutrients with a reduction of temperatures of the interior surfaces of the products between 0.22 °C and 0.88 °C, respectively. The reutilization of residual raw materials from alternate construction industries is a sustainable consideration to evaluate new possibilities for the manufacture of products with less embedded energy and, therefore, with a lower carbon footprint than traditional fired clay products.

Effect of layer thickness on anticorrosive performance of 316L steel coated with bismuth-titanium films

GARZÓN AGUDELO, PEDRO | 2021-05

. Bismuth and titanium are elements with remarkable properties and applications in technological developments and in the field of biomedical engineering. The sol-gel method was used to form a bismuth-titanium system, which allowed to establish if it was possible to obtain films with anticorrosive properties on 316L stainless steel. The anticorrosive response was evaluated by means of Tafel curves, defining the parameters to obtain thin and functional films with good tribological properties. The coatings were obtained by the spin coating technique, varying the spin speeds from 3000 rpm to 5000 rpm with monolayer and bilayer systems. More positive values of corrosion potential were obtained when the steel is coated by the films, which implies a lower propensity to corrosion in saline medium, lower corrosion rates and higher potentials are reported for films with higher titanium content, likewise, better efficiency of the films with respect to the uncoated substrate is presented, the higher the titanium content and a strong influence between the calculated efficiencies and the centrifugation speeds is not observed

High-Temperature Corrosion Behavior of Bi3.75La0.25Ti3O12 and Bi3La1Ti3O12 Coating Prepared by rf Magnetron Sputtering

Bautista Ruiz, Jorge | 2022-09-23

: Using the rf magnetron sputtering technique, Bi3.75La0.25Ti3O12 and Bi3La1Ti3O12 coatings were formed and obtained as a thin film on Hastelloy substrates. When subjected to high-temperature conditions, the effect of lanthanum on the anti-corrosive properties of the coatings was investigated. The anti-corrosive response was evaluated by electrochemical impedance spectroscopy and potentiodynamic curves, which are rarely reported. Hot corrosion occurs through the electrochemical mechanism, and more information can be obtained through electrochemical corrosion tests, which are very effective and fast. The electrochemical behavior at high temperatures was studied via molten salt corrosion tests, potentiodynamic polarization curves, and electrochemical impedance spectroscopy. Additionally, the coatings were evaluated via scanning electron microscopy and transmission microscopy to determine their morphology. With X-ray diffraction, the crystallinity of the films was determined. It was determined that the corrosion rate directly correlates with the temperature, attributed to the mechanisms induced by the Na2SO4 and V2O5 salts that generated condensation. As the temperature increases, the density of the corrosion current increases in the thin films of Bi3.75La0.25Ti3O12 and Bi3La1Ti3O12. When comparing the two compounds, it is determined that the increase in lanthanum alters the positive acid character, thus reducing the dissolution of the oxides and increasing protection.

Determination of the efficiency of hafnium carbide and tantalum carbide coatings deposited on exchange membrane fuel cells

Ruiz Madera, C | 2021-10

“Una comunidad, Un Producto” Fortalecimiento del Sector Cerámico Artesanal de Cúcuta en la construcción de su producto identitario

Sanchez Molina, Jorge | 2020-02-02

El proyecto busca fortalecer a las unidades productivas artesanales de la cerámica de Cúcuta y su área metropolitana, mediante el mejoramiento de las etapas del proceso productivo, a través de las siguientes líneas de acción: capacitación y asesoría en procesos productivos, desarrollo de productos, organización, tecnología y uso de derechos de propiedad intelectual. Se destaca que en el proyecto intervienen de forma articulada el Centro de Investigación de Materiales Cerámicos y tres grupos de Investigación de la Universidad Francisco de Paula Santander, en apoyo a organizaciones del sector publico y privado como actores claves en el esfuerzo por el fortalecimiento de la cerámica artesanal en la región, siendo este proyecto considerado como el inicio de un apoyo pertinente y sostenido en el tiempo, mediante alianzas estratégicas.

Effect of the addition of rice husk in technological properties of materials for the manufacture of ceramic

Bautista-Ruiz, Jorge | 2021-06

In this study, the rice husk discarded by the agro-industrial rice company in the department of Norte de Santander (Colombia) was used to replace clay material in the manufacture of tile-type ceramics. The materials were used to make test specimens with the presence of 5%, 10%, 15%, and 20% (weight) of scale and with three different types of grain size (1180 µm, 180 µm, and 75 µm mesh through). The specimens were molded using the extrusion technique. The shaped materials were subjected to different firing temperatures (900 °C, 1000 °C, 1100 °C, 1150 °C, and 1200 °C) to establish correlations between the microstructure/topography of the material and some of the technological properties of the ceramic such as the mechanical resistance to bending, resistance to deep abrasion, percentage of water absorption and linear drying/cooking shrinkage. The results show that proportions higher than 10% of rice husk do not obtain ceramics with ideal technological properties for use as pavement or coating. The best results were obtained when the husk was used at 5% and 180 µm mesh through grain size. The X-ray diffraction analysis of the cooked samples shows significant changes in the proportion of phases formed (test tubes with and without substitution of clay material) as the temperature increases.

Production of electroplated rhenium coatings using pulsating currents

| 2021-06

Rhenium was the most interesting material because it can be oxidized at high temperatures, so it is a promising applicant in biomedical applications. Its high melting point requires techniques such as electro-coating to produce it in thin-film formation, using a current of 40 mA/cm2 , in a cathode pulse and 4 mA/cm2 , in anodic form, the variation in temperature of the acid electrolytic bath being realized in a range of 60 to 85±2 °C. The temperature variation of the samples allowed to correlate their response to the degradation phenomenon. The topographical evaluation using atomic force microscopy on the surface of the samples permitted to indicate that a tendency of the roughness to reduce with the increase of the temperature up to 80 °C existed, an electrochemical evaluation was generated using Tafel polarization curves, immersed in a Ringer's lactate solution with a temperature of 37 °C, has now been subsequently performed using the scanning electron microscope, the surface analysis of the coatings, demonstrating that at deterioration is negligible, but when increasing the temperature to 80 °C, the deterioration is imperceptible when the type of surface damage is unobservable, however in the case of 85 °C the deterioration is observable.

Museums of geological and mining heritage. Case study for El Suspiro mine (Cúcuta, Colombia)

Castro Duque, Yesid | 2021-06

This work provides information on several existing museums in the region of Cúcuta (Colombia), which have elements that can be considered geological or mining heritage. These museums could be integrated into the creation of a mining theme park in conjunction with the closure of the El Suspiro limestone mine. The objective of this study, in addition to disseminating the information, is to show the existing museums at the municipalities of Los Patios and Cúcuta, where there are collections of fossils, minerals and archaeological elements found in the region. Additionally, there are enginery and elements that were used for mining development in the region as well as in the School of Mining Engineering at the Universidad Francisco de Paula Santander (UFPS). The methodology of this study involved an analysis of the topic at global, national and local contexts, visits to the museums and the mine site, as well as photographic records and geo-positioning. It is concluded that it is feasible to implement geotouristic visits at the El Suspiro limestone mine, as well as visits to the existing museums in Agualinda and Vados counties, and the museum of geological and mining heritage of the Universidad Francisco de Paula Santander at Cúcuta, Colombia.

DISEÑO DE UN PRODUCTO DE CONSTRUCCIÓN DE CONCRETO REFORZADO CON FIBRAS DE VIDRIO Y CON FIBRAS A PARTIR DE SUB-PRODUCTOS INDUSTRIALES

Sanchez Molina, Jorge | 2021-08-25

El concreto es un material que ha sido utilizado desde la antigüedad en la construcción de edificaciones que han sobrevivido el paso de los años. El concreto a su vez ha sido foco de investigación por muchos científicos a nivel mundial, quienes tienen como propósito optimizar las propiedades físicas y mecánicas para el mejoramiento continuo del material en cuanto a manejabilidad, resistencia y durabilidad. Diversas fuentes han reportado que desde la antigüedad se hacia el uso de materias primas diferentes a las convencionales (arena, cemento y grava) para la fabricación de concreto, tal es el caso del uso de crin de caballo adicionadas a morteros, y la paja para reforzar ladrillos de barro. En la actualidad, reforzar concreto con hebras o hilos tienen un nombre específico, el cual es conocido como concreto reforzado con fibras. Las fibras pueden ser de muchas procedencias; ya sean artificiales como lo es el caso de las fibras de plástico (polipropileno y el polietileno tereftalato-PET), las fibras de vidrio y las fibras metálicas, de hierro o acero; o también pueden ser fibras de procedencia natural (de origen animal o vegetal), como es el caso de las fibras de bagazo de caña de azúcar, paja, lechuguilla, estopa de coco, plumas de aves, entre otras. El uso de las fibras para reforzar concreto se da con el fin de mejorar ciertas características del concreto, tal como la resistencia a la flexión y la resistencia a la tracción, pero sin dañar propiedades como la densidad, la resistencia a la compresión y el módulo de elasticidad. Además, en muchos casos el uso de fibras se da con el fin de utilizar aquellos desechos y/o sub-productos industriales a los cuales no se les da un correcto manejo y terminan contaminando el medio ambiente. Por lo tanto, el presente proyecto tiene la finalidad de fabricar concreto con fibras de vidrio, las cuales han sido catalogadas por muchos investigadores como las mejores fibras para reforzar concreto, y compararla con fibras naturales a partir de desechos y/o sub-productos industriales, e identificar cuales fibras presentan mejoras en las condiciones del concreto (contrastado con concreto convencional). La investigación hace parte de un desarrollo tecnológico y experimental, es de tipo cuantitativa y descriptiva, ya que la investigación pretende conocer la estructura y la funcionalidad de un concreto especial diseñado con fibras de vidrio y con fibras a partir de sub-productos industriales. Los resultados esperados con el desarrollo del proyecto son los siguientes: formar a dos jóvenes investigadores, los cuales están siendo financiados por MinCiencias a través de la convocatoria 891; generar conocimiento a través de la publicación de un artículo científico en una revista categoría B; y generar la apropiación de conocimiento a través de la participación en la modalidad de ponencia en un evento nacional o internacional.

Mineralogical characterization of zeolites present on basaltic rocks from Combia geological formation, La Pintada (Colombia)

Gelves Diaz, John Freddy | 2016-11

The present study report the presence of natural zeolites, which were found in the andesitic basalts from the Combia geological formation, municipality of La Pintada, Antioquia department (Colombia). The collected samples were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with detector X-ray energy dispersive (SEM/EDX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and polarized light optical microscopy (PLOM). The results shown the presence of an associated zeolites heulandite group with predominance of heulandite phase rich in calcium and potassium, with prevalence of platy habit and in a lesser extent the habit coffin type, tabular and block were also evidenced. The presence of chabazite, phillipsite and mordenite, were evidenced as minority zeolites phases. Based on the zeolites properties, the phases founded in Combia formation could be an interest materials for technological applications in areas such agriculture, catalysis or gas separation applications. Especially in Colombia this kind of mineral can be important because much of the current consumption is imported from other territories.

Estrategias para mejorar la productividad y competitividad de las empresas de calzado de Cúcuta

Monroy Sepulveda, Richard | 2017

La presente investigación tiene como objetivo plantear estrategias para mejorar la productividad y competitividad de las empresas de calzado de Cúcuta. La población estuvo conformada por 32 empresas de calzado de Cúcuta, que se encuentran actualmente funcionando (carácter legal). La elaboración de las estrategias partió de un análisis interno de la cadena de valor de las empresas de calzado de Cúcuta y posteriormente de un análisis externo, conformado por el análisis del diamante de PORTER, las 5 fuerzas competitivas y las fuerzas macroambientales, económicas, tecnológicas y ambientales. Se determinó la posición competitiva a través de la Matriz de Evaluación Interna-Externa. Desde la posición competitiva, se elaboraron las estrategias y los planes de acción para mejorar la competitividad y productividad.

Análisis de las propiedades físico cerámicas y efectos superficiales en un tipo de pasta cerámica, sometida a proceso de modelado mecanizado CNC por sustracción material, para la vinculación de un nuevo modelo de fabricación en la industria cerámica regio

Maldonado M, Alvaro E | 2018

La investigación se desarrolla a partir del análisis superficial y físico cerámico en una pasta cerámica debidamente caracterizada; pasta atomizada que mediante proceso de extrusión se obtienen las muestras de arcilla que van a estar sometidas a un modelado mecanizado CNC por sustracción antes del proceso de cocción, las cuales son revisadas mediante Microscopia Óptica para analizar los cambios que se presentan a nivel de superficie. El estudio de los cambios superficiales o alteraciones en las propiedades físico cerámicas que se producen en este material por el proceso de mecanizado, es relevante para determinar con exactitud las alteraciones que se presentan en el material y la ejecución de las mismas piezas fabricadas mediante este proceso; el cual puede dar paso a diseños de morfologías de alta eficiencia energética e incorporar procesos de producción más consecuentes con las políticas ambientales en relación al impacto actual que la industria cerámica produce en la región. Es importante destacar que la investigación tiene como objetivo proponer un modelo más de producción cerámica, en la industria regional, el cual articula los nuevos medios de Fabricación Digital, ofreciendo a la industria regional nuevos desarrollos de alta competitividad a nivel nacional e internacional. Por ultimo las reflexiones económicas y ambientales de esta propuesta giran en torno al desarrollo de espacios productivos, que permitan a los proyectistas establecer nuevas soluciones de diseño, a problemáticas que están sujetas a la forma de cómo pensamos nuestro modo de habitar y de cómo construimos nuestras ciudades en un entorno de producción de bajo impacto ambiental.

Caracterización Anticorrosiva y de Biocompatibilidad en Recubrimientos Silicio-Titanio-Zirconio Sintetizados Vía Solgel y Depositados sobre Sustratos 316L

Bautista-Ruiz, Jorge | 2018-02

Se sintetizaron, los sistemas ternarios [Si/Ti/Zr: 10/70/20] y [Si/Ti/Zr: 10/20/70] vía sol-gel y se aplicaron sobre sustratos de acero inoxidable 316L mediante la técnica de inmersión. En los recubrimientos obtenidos se evaluó la respuesta anticorrosiva en una solución fisiológica simulada mediante curvas potenciodinámicas de polarización. Se estudió la biocompatibilidad celular de osteoblastos; la adhesión sustrato-recubrimiento; la topografía superficial, el espesor y la rugosidad en los recubrimientos. Los resultados de este estudio permiten establecer un alto grado de efectividad anticorrosiva y buena biocompatibilidad. Los recubrimientos sintetizados vía sol-gel establecen su potencialidad como barrera anticorrosiva en función del sistema ternario aplicado al sustrato de acero inoxidable 316L.

Synthesis of oxygenated compounds from methane, carbon dioxide and liquid water using non-thermal plasma

Gelves Diaz, John Freddy | 2018-02

Oxygenated compounds were obtained from methane and carbon dioxide using the unconventional activation by dielectric barrier discharge plasma. The process was performed using a multiphase feed composed of methane, liquid water and carbon dioxide as oxidizing agent. The effect of the CH4/CO2 ratio as well as the flow of liquid water were investigated. The results show that the presence of liquid water in the reactor favors the formation of oxygenated compounds. A direct proportional relation between the flow of water, concentration of methane in the gaseous feed (in the presence of water) and the amount of the produced oxygenates was observed. The highest value of selectivity towards oxygenated compounds was 21.2%, with methanol and formic acid being the main products formed.