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Treatment of subterranean mining water through filtration using ceramic bilayer membranes based of recycled diatomites and kaolin

RIVERA, SILVIA FERNANDA; Salazar Ayala, Karen Andrea; Peña Rodriguez, Gabriel (Contemporary Engineering SciencesSofia , Bulgaria, 2018-10-22)

The treatment of underground wastewater is presented. Used at the San Martín 5 mine in the San Roque sector of the municipality of Sardinata (Norte de SantanderColombia); through the process of filtration through bilayer ...
Arduino data-logger and artificial neural network to data analysis

Hector Jaime, Dulce-Moreno; Contreras Contreras, G F; Ardila Melo, R (Journal of Physics: Conference SeriesBogota , Colombia, 2019-11-29)

This work takes thermodynamic modelling through computer science for incubation process at domestic birds, that has presented energy consumption significantly high than energy used in processes. Thus, a data analysis was ...
Design and manufacture of the cooling system of JUPITER reactor

Hector Jaime, Dulce-Moreno; Gélvez Arocha, O A; Dugar-Zhabo, V D; Rodríguez-Villamiza, C D; V-Niño, E D (Journal of Physics: Conference SeriesBogota , Colombia, 2019-02-25)

The experimental investigations carried out in the Plasma laboratory of the Universidad Industrial de Santander, on superficial modification of metallic materials by hybrid discharges of high-voltage and electric arc at ...
Tortuosidad y permeabilidad de materiales cerámicos mesoporosos de caolín y diatomita

FONSECA PÁEZ, LUIS ALEJANDRO; Peña Rodriguez, Gabriel; Trujillo-Castro, Emanuel (Revista UIS IngenieríasBogota , Colombia, 2019-01-01)

Se reporta la permeabilidad y tortuosidad de cerámicas mesoporosas de caolines y diatomitas. Las muestras cilíndricas con porcentaje en peso de 60 % diatomita, 30 % caolín y 10 % CaCO3, fueron elaboradas por colado, con ...
Aplicación de FeO, ZnO y CuO como pigmentos en compuestos cerámicos

ROA BOHÓRQUEZ, KAROL LIZETH; PAREDES ROA, RICARDO ALFONSO; LARA GONZÁLEZ, LUIS ÁNGEL; Peña Rodriguez, Gabriel (Informador TécnicoBogota , Colombia, 2019-04-12)

Entre los problemas más relevantes de la industria alfarera de Boyacá, Colombia, se encuentra la ausencia de una gama de tonalidades uniformes de sus productos finales. El color, por tratarse de una propiedad física ...
Effective thermal properties of a magnetite-polyester composite conformed in the presence of a constant magnetic field

LARA GONZÁLEZ, LUIS ÁNGEL; Peña Rodriguez, Gabriel; Pineda Triana, Yaneth (AIMS Materials ScienceWashintong D.C , Estados Unidos, 2019-07-02)

In this study, we report the thermophysical properties (at room temperature) and the morphology of a composite with a polyester resin matrix and magnetite filler powders (Fe3O4), conformed in three configurations: randomly ...
Coating of tricalcium phosphates by flame spray

Ferrer, Martha; García-Páez, Ismael H.; Rodríguez, Luis Francisco (Journal of Physics: Conference Series, 2019-11-29)

The metal alloys used for prostheses with high mechanical requirements are bioinerts, it means they have low integration with bone tissue, therefore, bioactive coatings are used in order to improve this integration. ...
Microstructure, physical and mechanical properties of kaolin - diatomite composite reinforced with CaCO3

ROA BOHÓRQUEZ, KAROL LIZETH; Vera López, Enrique; FONSECA PÁEZ, LUIS ALEJANDRO; Peña Rodriguez, Gabriel (DYNA, 2019-07-01)

The present work reports the microstructure, physical and mechanical properties of a material composed of kaolin, diatomite and calcium carbonate reinforcement (CaCO3). The ceramic prototypes were shaped by the slip casting ...
Determination of correlation of compressive strength with maturity of concrete mixed with accelerator

Peña Rodriguez, Gabriel; Medrano Lindarte, Carmen Teresa; García-Páez, Ismael H. (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

The compressive strength of concrete mixtures with accelerator additives designed for structural elements with strength of 5000 psi was correlated with the maturity index of concrete at an early age. The design of the ...
Application of maturity method to estimate compressive strength of mass concrete

Gamba Gomez, Osmar Albert; Pineda Triana, Yaneth; Peña Rodriguez, Gabriel (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

The correlation between the maturity index and the compressive strength of concrete is validated for mixtures with strengths of 2000, 2500, 3000 and 3500 PSI, which are the most used in the civil engineering field. Temperature ...
Use of recycled diatomaceous earth from breweries as a means of transporting of macronutrients

Peña Rodriguez, Gabriel; Rodriguez Aguilar, Marlon Hans; BECERRA, EVER; Caballero, Xandro; Hector Jaime, Dulce-Moreno (Revista UIS IngenieríasBogota , Colombia, 2019-09-16)

Se reporta la caracterización físico-química de tierras diatomáceas recicladas de la industria cervecera, y su uso como medio de transporte de macronutrientes (Nitrógeno, Fósforo, Potasio (NPK)), con el fin de dar una ...
Obtaining and characterizing of WC-Co coatings obtained from thermal spray by flame

Peña Rodriguez, Gabriel; Ferrer, Martha; Rodriguez Wilches, Luis Francisco (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

Tungsten carbide is used in the production of cutting tools for steel and as protection against wear due to its extremely high hardness. High speed oxygen fuel spraying process has been widely used to deposit WC-Co coatings. ...
Modelling the effect of temperature on the physical and mechanical properties of ceramic composites filled with foundry sand waste

Peña Rodriguez, Gabriel; ROA BOHÓRQUEZ, KAROL LIZETH; PAREDES ROA, RICARDO ALFONSO; Vera López, Enrique; Castro, HF; Trejo, F (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

The aim of this research is to describe the temperature effect on the water absorption, linear shrinkage, density and compressive strength of ceramic composites produced by mixing clay with additions of foundry sand waste ...
Characterization of commercial luminescent powders

Peña Rodriguez, Gabriel; Paredes Roa, Ricardo Alfonso; Roa Bohorquez, Karol Lizeth; Castro, H F (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

Luminescent powders have attracted the attention of scientists, boosting properties as specific as mechanoluminescence, thermoluminescence, and photoluminescence among other characteristics. The uses of these properties ...
Design and characterization of a magneto-dielectric composite in high frequency with aligned magnetite powders

Peña Rodriguez, Gabriel; Mancipe, D L; Pineda Triana, Yaneth; LARA GONZÁLEZ, LUIS ÁNGEL; Moreno, J J (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

A magneto-dielectric material composed of a polyester resin-based microstrip (P115A), copper sheets and magnetite powders was designed in concentrations of 10, 20 and 30% Wt and with filters of 200, 325 and 500. The particles ...
Effect of concentration of starch in the properties morphological and structural of porous ceramic based on expansive clays

Peña Rodriguez, Gabriel; Dulce Moreno, Hector Jaime; Ferrer Pacheco, Martha Yasmid; Suarez, M; Bermudez, D (Journal of Physics: Conference SeriesLondres, Reino Unido, 2020-03-06)

In this article is used the sacrificial material method to generate different porosities between 44.42% and 69.14% in ceramics based on expansive clays from San Jose de Cúcuta metropolitan area, Colombia, to analyze the ...
Optimization of the Tensile Properties of Polymeric Matrix Composites Reinforced with Magnetite Particles by Experimental Design

LARA GONZÁLEZ, LUIS ÁNGEL; RODRÍGUEZ LÓPEZ, WILMAR GUILLERMO; Pineda Triana, Yaneth; Peña Rodriguez, Gabriel; Felipe, Hugo (TecnoLógicasBogota , Colombia, 2020-05-15)

A full-factorial 33 experiment was used in this study to determine the optimal values of the tensile properties of three composite materials manufactured based on three polymeric resins: Derakane Momentum epoxy vinyl ester ...
Design and simulation of a mechanical system for the machining of parts and printing in 3D (x, y, z)

Miranda Molina, Luis Antonio; Quinayas Ortiz, Asdrúbal Maximino; Peña Rodriguez, Gabriel (Revista UIS Ingenierías, 2020-07-30)

The design and simulation of a multifunctional system for the machining of mechanical parts and printing in 3D (x, y, z) using CAD software Solid works, was used to determine the static behavior of the system with the ...
Obtaining and characterization of nanostructured coatings of zirconiaalumina- ceria by thermal spray flame

Peña Rodriguez, Gabriel; Ferrer, Martha; Rodriguez Wilches, Luis Francisco (Journal of Physics: Conference Series, 2019-11-19)

Zirconia, alumina and ceria powders were agglomerated, by granulator disk, to be used as raw material in the manufacture of coatings on red clay substrates by flame spray. Three mixtures of different compositions were made ...

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Treatment of subterranean mining water through filtration using ceramic bilayer membranes based of recycled diatomites and kaolin
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RIVERA, SILVIA FERNANDA | 2018-10-22

The treatment of underground wastewater is presented. Used at the San Martín 5 mine in the San Roque sector of the municipality of Sardinata (Norte de SantanderColombia); through the process of filtration through bilayer porous membrane (diatomite-kaolin / kaolin) based on recycled diatomite from the brewing industry and kaolin. The water samples were looked at before and after the filtration process, taking as reference the maximum values allowed by resolution 0631 of 2015. The analyzed parameters were Suspended solids, BOD5, COD, pH, Fe, dissolved solids. The porous cylindrical ceramics, 5 cm in diameter and 0.9 cm thick, were formed by casting using the plaster mold, where the layer of 100% kaolin with a thickness of approximately 0.3 cm was first deposited. applied the second layer from pulps with weight percentage of 50% recycled diatomite from the brewing industry, 40% kaolin, and 10% calcium carbonate. Once the ceramics are carried out, they aresubject to the drying process at room temperature for 24 hours, then by means of the forced circulation oven Memmert UF-110 at 100 ° C for an equal time. The sintering of the ceramic was carried out in Vulcan D-130 electric muffle, at a maximum temperature of 1000 ° C for two hours, with a heating ramp of 10 ° C / min. The morphology of the ceramics was studied using scanning electron microscopy (SEM), while physical-ceramic analyzes were performed in accordance with ISO 10545-3. The results show that the ceramic membrane is, in fact, 52% for the reduction of total solids, while the elimination of iron is 38%, on the other hand, it is also evident that the ceramics are not effective in the treatment of dissolved solids with high concentrations

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Arduino data-logger and artificial neural network to data analysis
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Hector Jaime, Dulce-Moreno | 2019-11-29

This work takes thermodynamic modelling through computer science for incubation process at domestic birds, that has presented energy consumption significantly high than energy used in processes. Thus, a data analysis was applied upon variables of temperature and relative humidity for heating zones, trying to know how much energy supplied by source was used, as well as, voltage and current variables are measured in the same moment that temperature and relative humidity are acquired. Then, data analysis was done using artificial neural networks models with samples obtained from sensors, where real process is highly time- variant, fixing environment conditions at the moment required. Therefore, with this system has been obtained an air flow of 3.4375 10−2 m3/J using a anemometer respect to electrical energy supplied by fans, giving 9.4818 W of average power using ceramics resistances, and testing an adaptive controller where its variables are fitted using equations obtained from data analysis. In contrast, colombian farmers have decreased economic conditions to maintain them productions due to free trade agreements implemented lastly, indeed this system was developed using open- source software and hardware to avoid costs in acquisition by licensing politicians or periodic subscription to a specific product developed by companies.

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Design and manufacture of the cooling system of JUPITER reactor
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Hector Jaime, Dulce-Moreno | 2019-02-25

The experimental investigations carried out in the Plasma laboratory of the Universidad Industrial de Santander, on superficial modification of metallic materials by hybrid discharges of high-voltage and electric arc at low pressures are carried out in the joint universal plasma and ion technologies experimental reactor. The cooling system of the reactor is by water, which means that it is directly connected to the water supply line of the building, which creates a dependence on the system. Additionally, the water supply line is often filled with particles that accumulate in the cooling system, disfavoring the transfer of energy between the water, the vacuum system and the cathode, which can lead to overheating of the reactor and melt the elements that make up the electric power system. In accordance with the above, the present research work consists of designing, building and implementing an efficient cooling system totally independent from the water supply line of the building, which allows to recirculate and minimize water consumption in order to take care of the natural resource.

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Tortuosidad y permeabilidad de materiales cerámicos mesoporosos de caolín y diatomita
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FONSECA PÁEZ, LUIS ALEJANDRO | 2019-01-01

Se reporta la permeabilidad y tortuosidad de cerámicas mesoporosas de caolines y diatomitas. Las muestras cilíndricas con porcentaje en peso de 60 % diatomita, 30 % caolín y 10 % CaCO3, fueron elaboradas por colado, con diámetro promedio de 5 cm y espesor de 0,6 cm. El proceso de secado se realizó mediante estufa de circulación forzada a 100 °C por 24 horas, la sinterización a temperaturas de 800 °C, 850 °C, 900 °C, 950 °C, 1.000 °C y 1.100 °C, usando una mufla eléctrica con una rampa de 5 °C/min. Para la determinación de permeabilidad por el agua, se utilizó un permeámetro de carga variable, mientras que la tortuosidad se halló del producto del factor de forma y su porosidad. Se encontraron resultados de tortuosidad en el rango de 3,32 a 7,16, mientras que la permeabilidad varió entre 3,09x10-6 y 22,2x10-6 cm/s, evidenciándose un comportamiento inverso entre estos parámetros al incrementarse la temperatura.

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Aplicación de FeO, ZnO y CuO como pigmentos en compuestos cerámicos
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ROA BOHÓRQUEZ, KAROL LIZETH | 2019-04-12

Entre los problemas más relevantes de la industria alfarera de Boyacá, Colombia, se encuentra la ausencia de una gama de tonalidades uniformes de sus productos finales. El color, por tratarse de una propiedad física fácilmente observable, se convierte en un criterio distintivo para clientes potenciales que buscan un producto diferenciador y a la vanguardia dentro de un medio en constante cambio. Por tal razón, el presente trabajo propuso un compuesto cerámico elaborado a partir de arcillas montmorillonitas y óxidos metálicos tales como FeO, CuO y ZnO. Las arcillas se caracterizaron por Fluorescencia de Rayos X (FRX) y de acuerdo a la composición química de cada arcilla, se determinaron las concentraciones de los óxidos metálicos como agentes colorantes, los cuales variaron de 1 a 8 % (en peso). Los prototipos cerámicos se conformaron por el método de prensado uniaxial a una presión de compactación constante de 15 MPa, posteriormente se sinterizaron a 950 °C durante 2 h. Mediante histogramas RGB se realizaron los análisis de color de los especímenes, los resultados mostraron cambios significativos en la pigmentación del compuesto cerámico reportando tono rojo, café y blanco. Lo anterior, hace viable la utilización de estos óxidos como pigmentos termoestables en la elaboración de productos cerámicos tales como: tejas, tabletas y baldosas, entre otros diseños cerámicos que hoy en día solo se pueden encontrar en tiendas de cerámica avanzada.

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Effective thermal properties of a magnetite-polyester composite conformed in the presence of a constant magnetic field
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LARA GONZÁLEZ, LUIS ÁNGEL | 2019-07-02

In this study, we report the thermophysical properties (at room temperature) and the morphology of a composite with a polyester resin matrix and magnetite filler powders (Fe3O4), conformed in three configurations: randomly dispersed particles, particles oriented parallel to a constant 300 mT magnetic field, and particles oriented perpendicular to a constant 300 mT magnetic field. Samples were formed by hand lay-up with weight percentages of 10, 20 and 30%, where the highest concentration corresponds to the resin. The thermophysical properties were determined using the KD2 Pro® system, which uses the physical principle of linear transient heat flow, for which the dual sensor SH-1 was used. The morphology and microanalysis were studied using a scanning electron microscope (SEM, FEI Quanta 650 FEG). It was observed from the morphology that the magnetite particles are oriented in the direction of the magnetic field lines during the process of resin curing. It was also perceived that the values of the thermophysical properties found experimentally are within the limits (upper and lower) of Hashin and Shtrikman and that those values increase when the magnetite concentration increases in the sample. No significant difference was observed in the thermal properties because of the magnetic field applied.

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Coating of tricalcium phosphates by flame spray
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Ferrer, Martha | 2019-11-29

The metal alloys used for prostheses with high mechanical requirements are bioinerts, it means they have low integration with bone tissue, therefore, bioactive coatings are used in order to improve this integration. Hydroxyapatite is one of the most studied materials for this application with good results, however, sometimes there are problems due to wear or tear of the coating leading prostheses loss. Tricalcium phosphate, Ca3(PO4)2, in its different phases shows osteoconductivity and higher solubility than hydroxyapatite, however, few studies have been carried out to determine its behavior as a coating for this type of applications. In this work, a study of the behavior of tricalcium phosphate as a coating on Ti6Al4V substrates obtained by flame spraying was carried out. As raw material were used tricalcium phosphate powders obtained by precipitation from calcium nitrate and ammonium phosphate dihydrogen solution, and subsequent calcination at 1,100°C. The Ca/P molar ratio obtained is 1.48 and the only present crystalline phase is beta -tricalcium phosphate. The coatings obtained have alpha tricalcium phosphate as only crystalline phase, they have compact morphology with low porosity and good wettability with the substrate, which is an index of good adhesion and good mechanical behavior. The transformation from beta- to alpha- tricalcium phosphate is product of the high temperatures used in the process, which are higher than 1,125°C where this transformation occurs.

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Microstructure, physical and mechanical properties of kaolin - diatomite composite reinforced with CaCO3
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ROA BOHÓRQUEZ, KAROL LIZETH | 2019-07-01

The present work reports the microstructure, physical and mechanical properties of a material composed of kaolin, diatomite and calcium carbonate reinforcement (CaCO3). The ceramic prototypes were shaped by the slip casting method and sintered at temperatures between 800 °C and 1100 °C. The morphology and average pore size was analyzed by Scanning Electron Microscopy (SEM) and the mineralogical phases were determined by X-Ray Diffraction (XRD). The apparent density was established by the mercury immersion method according to the E – 8B Standard of the Institute of Ceramic Technology (ITC); the percentage of absorption was determined by the boiling method according to ISO 10545-3 standard; linear contraction was studied in three directions: long, wide and high. The study of the mechanical resistance to compression followed the procedure established at ASTM C773–88 standard and the breaking modulus was calculated by the three-point bending test, according to ISO 10545–4. Results show that the material structure is affected with increasing temperature reporting a decrease in quartz phase from 51.16 % to 33.81 %. Percentage of absorption revealed its most significant variation between 950 °C and 1100 °C with a decrease of 21 % approximately. Mechanical resistance values showed wide dispersion which was attributed to the different orientations in which the material failed during each test. According to the pore diameters found, the compound is characterized by being macro and mesoporous facilitating its application in catalysis, photochemistry, microelectronics and other microfiltration media

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Determination of correlation of compressive strength with maturity of concrete mixed with accelerator
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Peña Rodriguez, Gabriel | 2019-11-29

The compressive strength of concrete mixtures with accelerator additives designed for structural elements with strength of 5000 psi was correlated with the maturity index of concrete at an early age. The design of the mixture was made by adding the quantity of additives according to the specifications of the supplier. The maturity index was calculated using the thermal profile of the concrete dependent of the setting time, which was obtained through an automated adiabatic system. The number of thermal sensors required for temperature measurement dependent of setting time (1, 3, 7, 14 and 28 days) was determined by a factorial experimental design of two factors. The correlation coefficient was 0.96, so the logarithmic model adequately explains the variability of the compressive strength. The equation obtained was validated by means of the values of resistance to compression measured by the standard method for each age of the concrete; all values are within the calibration range of the resistances estimated by the maturity method.

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Application of maturity method to estimate compressive strength of mass concrete
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Gamba Gomez, Osmar Albert | 2019-11-29

The correlation between the maturity index and the compressive strength of concrete is validated for mixtures with strengths of 2000, 2500, 3000 and 3500 PSI, which are the most used in the civil engineering field. Temperature probes DS18B20 connected by the 1-Wire protocol to the Raspberry Pi 3 card were used to census the data and calculate the maturity index. The concrete mixtures presented A/C ratios of 0.820, 0.748, 0.680 and 0.623, which are consistent with those used in the construction industry. Compressive strength tests were performed every 24 hours during a 28-day test scenario in order to understand the behavior of concrete throughout the curing process. From the values of mechanical resistance to compression obtained in the control ages of 7 and 14 days it is inferred that the concrete has a normal hardening, likewise when comparing the experimental results of the resistance to compression, with those found using the method of maturity, it was possible to identify that at early ages (less than 10 days) they present uncertainties greater than 10% while at ages greater than 10 days of curing this error does not exceed 5%. In general, it was evidenced that the assembly carried out with the Raspberry pi 3 card and DS18B20 probes reliably allowed the monitoring, recording and storage of temperature and time data during the entire curing process.

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Use of recycled diatomaceous earth from breweries as a means of transporting of macronutrients
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Peña Rodriguez, Gabriel | 2019-09-16

Se reporta la caracterización físico-química de tierras diatomáceas recicladas de la industria cervecera, y su uso como medio de transporte de macronutrientes (Nitrógeno, Fósforo, Potasio (NPK)), con el fin de dar una alternativa amigable con el ambiente, a los desechos generados en el subproceso de filtración de la cerveza. Para la conformación de las muestras (pellets) por extrusión, se utilizó como aglutinantes carboximetilcelulosa (CMC) y fécula de maíz, mientras que la humectación se llevó a cabo usando una solución líquida comercial con 15 % de NPK, en concentración baja, media y alta, la cual se agregó durante el proceso de conformado de los pellets. La caracterización química de las muestras se realizó usando espectroscopía de absorción atómica (AA), y microanálisis mediante espectroscopia de energías dispersas (EDS), la morfología superficial se estudió usando microscopia electrónica de barrido (MEB). El comportamiento de la capacidad de devolución de los macronutrientes a un medio acuoso se llevó a cabo por medio del análisis de la conductividad eléctrica (EC) y sólidos totales disueltos (TDS) en función del tiempo mediante el multiparámetro SI Analytics 680 K. Se encontró que la muestra que no presentó pérdida de su estructura en medio acuoso fue la conformada por 60% de diatomita, 10% de CMC y 30% de fécula de maíz (%w/w). También se evidenció un incremento en el tiempo de la EC y TDS de la solución acuosa cuando se sumergían los pellets activados, infiriéndose que éstos son un buen medio se trasporte de macronutrientes, los cuales podrán ser usados como abono en aplicaciones agrícolas coadyuvando al medio ambiente

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Obtaining and characterizing of WC-Co coatings obtained from thermal spray by flame
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Peña Rodriguez, Gabriel | 2019-11-29

Tungsten carbide is used in the production of cutting tools for steel and as protection against wear due to its extremely high hardness. High speed oxygen fuel spraying process has been widely used to deposit WC-Co coatings. However, the decomposition and oxidation of WC-Co has been reported during the process, where carbon and tungsten are released, resulting in the formation of an amorphous matrix with the cobalt of the compound. This is attributed to the high heating and cooling rates suffered by the raw material. An alternative method is the thermal spray by flame, which allows controlling the working temperature and the residence time of the particles in the hot flame, avoiding the decomposition of tungsten carbide, on the other hand, it is a versatile and a low cost method. In this study projection parameters of a WC-18Co coating sprayed with a thermal flame spraying process from a commercial feedstock powder were determined to decide the conditions under which compact coatings are obtained with low porosity, avoiding dissociation of the tungsten carbide. The composition of the powders and substrates was determined by X-ray fluorescence microscopy and optical emission, respectively, X-ray diffraction studies were performed to characterize compositions and microstructures the coatings sprayed; the morphology was by scanning electron microscope. It was found that the best condition for this type of coatings is a neutral flame at a projection distance of 12 cm.

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Modelling the effect of temperature on the physical and mechanical properties of ceramic composites filled with foundry sand waste
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Peña Rodriguez, Gabriel | 2019-11-29

The aim of this research is to describe the temperature effect on the water absorption, linear shrinkage, density and compressive strength of ceramic composites produced by mixing clay with additions of foundry sand waste from 20% to 40% wt. Previous studies have shown that foundry sands can be recycled due to the high content of SiO2 on its chemical composition, therefore, in this research is proposed as an alternative raw material in ceramic bodies. Prototypes were shaped by uniaxial pressing method and fired at three different temperatures (850°C, 950°C and 1,050°C) in order to promote the formation of the ceramic phases. Physical and mechanical properties were measured based on the procedures specified by standard ASTM C373 and ASTM C773-88. It was found that at 1,050°C properties such as mechanical strength and density reach its maximum values, effect that might be associated to the reduction in pore size inside the microstructure during calcination. The main merit of the models obtained is offer a valuable tool to set up a proper thermal process in order to obtain eco-friendly ceramic samples with physical and mechanical properties at its optimum values, reducing environmental problems related to landfill disposal and minimizing costs of manufacturing.

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Characterization of commercial luminescent powders
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Peña Rodriguez, Gabriel | 2019-11-29

Luminescent powders have attracted the attention of scientists, boosting properties as specific as mechanoluminescence, thermoluminescence, and photoluminescence among other characteristics. The uses of these properties have grown exponentially from recreational uses in luminescent paints, toys, plasticines, and other industry-specific uses, such as crack sensors, flaw detectors, and radiation meters in medicine. These uses have grown proportionately with their more economical and efficient manufacturing methods and processes, generating more economical fluorescent pigments. This paper characterizes and compares a low-cost luminescent pigment with those reported by different authors, its chemical composition was characterized by X-ray energy dispersion spectrometry, X-ray fluorescence, and Raman spectroscopy. Its morphology was analyzed by scanning electron microscopy, and its particle size with a laser meter its structural condition with X-ray diffraction, the powder obtained was presented as a strontium alumínate doped with divalent europium and trivalent dysprosium (Al2O4: Eu2+, Dy3+) one of the most efficient powders around persistence and luminance intensity at present. The structure of the strontium aluminate was determined by the main peaks of the diffractogram showing a monoclinic system. The elemental composition helped to determine the doping of the strontium aluminate corroborating them with the obtained with Raman spectroscopy and the scanning electron microscopy images.

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Design and characterization of a magneto-dielectric composite in high frequency with aligned magnetite powders
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Peña Rodriguez, Gabriel | 2019-11-29

A magneto-dielectric material composed of a polyester resin-based microstrip (P115A), copper sheets and magnetite powders was designed in concentrations of 10, 20 and 30% Wt and with filters of 200, 325 and 500. The particles were aligned vertically and horizontally during the curing process using 300 mT magnetic fields. From a complete factorial design of 33, 27 microstrip-type circuits of 4 mm width, 70 mm length and 0.93 mm thickness were manufactured, characterized by scanning electron microscopy and vector network analysis. The cross-matrix analysis determined an optimal circuit response from the magneto-dielectric material with a concentration of 20% magnetite and an average particle size of 21.48 μm in horizontal alignment to the applied magnetic field and to the transmission line, obtaining a relative dielectric constant of Er 3.88 with a low dielectric loss of 0.054, within an operating range of 150 KHz to 4 GHz.

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Effect of concentration of starch in the properties morphological and structural of porous ceramic based on expansive clays
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Peña Rodriguez, Gabriel | 2020-03-06

In this article is used the sacrificial material method to generate different porosities between 44.42% and 69.14% in ceramics based on expansive clays from San Jose de Cúcuta metropolitan area, Colombia, to analyze the effect of concentration of starch (porogenic agent) in the morphological and structural properties using calcium carbonate as a stabilizer. The porous ceramics was characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. Finally, the images were analyzed with the software Image J, Image Tool and Origin. The results showed that the weight concentration of starch has a relationship with the average pore size, the number of pores and the porous area of the samples where the percentage of porous area and the average pore size of the mixtures increases as starch is added due to the decay of the sacrificial material. The number of pores of the mixtures decreased by increasing the weight concentration of the starch due to the agglomeration of the starch.

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Optimization of the Tensile Properties of Polymeric Matrix Composites Reinforced with Magnetite Particles by Experimental Design
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LARA GONZÁLEZ, LUIS ÁNGEL | 2020-05-15

A full-factorial 33 experiment was used in this study to determine the optimal values of the tensile properties of three composite materials manufactured based on three polymeric resins: Derakane Momentum epoxy vinyl ester based on bisphenol-A (DM-411), polyester based on terephthalic acid (P115-A), and isophthalic polyester (P2000). Such materials were reinforced with magnetite powders at concentrations of 10, 20, and 30 wt %, and the particle sizes were classified with three sieves: #200 (46–75 μm), #325 (26–45 μm), and #500 (0–25 μm). The compounds were manufactured using the hand lay-up method at room temperature in accordance with ASTM D638-14 for M1-type specimens. A tensile test was conducted on a universal Microtest EM2/300/FR machine at a test speed of 5 ± 25 % mm/min using an Epsilon extensometer calibrated in accordance with the ASTM E83 standard at 20 ± 2 °C. The magnetite powders and compound morphology were studied by Scanning Electron Microscopy. The mechanical properties of the compounds and the optimal response found by Analysis of Variance (ANOVA) and Response Surface Methodology (RSM) are also reported. The best response to the mechanical stimuli occurs with the composite material prepared with the epoxy vinyl ester resin DM-411, a concentration of 29.4 % of magnetite (Fe3O4), a particle size of 58.5 microns, and a 200 sieve.

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Design and simulation of a mechanical system for the machining of parts and printing in 3D (x, y, z)
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Miranda Molina, Luis Antonio | 2020-07-30

The design and simulation of a multifunctional system for the machining of mechanical parts and printing in 3D (x, y, z) using CAD software Solid works, was used to determine the static behavior of the system with the analysis of tension, deformation, displacement, safety factor, buckling, fatigue and frequency. For the above, it was determined that the lateral base supports a tension of 3.5x108 Pa, causing a displacement of 25 mm and an equivalent unit strain (ESTRN) of 0.0012. And the base guiding a cumulative damage of 300% of deterioration that reduces its useful life to a range between 1x106 and 1x1065 utility cycles and a safety factor (F S) between 104.632 to 7869.86. On the other hand, the transverse base has a maximum cumulative damage percentage of 4.10535 and a life cycle range ranging from 24358.5 to 1x106 with a minimum SF of 5974

LEER
Obtaining and characterization of nanostructured coatings of zirconiaalumina- ceria by thermal spray flame
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Peña Rodriguez, Gabriel | 2019-11-19

Zirconia, alumina and ceria powders were agglomerated, by granulator disk, to be used as raw material in the manufacture of coatings on red clay substrates by flame spray. Three mixtures of different compositions were made to determine which of them produces the most homogeneous and best bonded coatings. Likewise, the phase transformations that occur in the thermal spraying process were evaluated. The morphology and microstructure of the powders and coatings were determined by scanning electron microscopy and X-ray diffraction, respectively. Bimodal coatings were obtained, preserving the nanometric structure of the powders, homogeneous, low porosity and good adhesion.

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