Mostrando 1 - 4 Resultados de 4 Para Buscar 'Paredes-Paz, J. J.', tiempo de consulta: 0.01s Limitar resultados
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artículo
The possibility of using biomass as a precursor of silicon carbide (SiC) has been studied for many years. In this research, reaction-formed silicon carbide was synthesized from sawdust residues of Peruvian wood. Residues were packed into cylindrical solid pieces through hot pressing and they were subsequently pyrolyzed in an inert atmosphere and infiltrated with metallic silicon in a vacuum atmosphere. SiC pieces were obtained with silicon remaining in their pores, so a chemical attack was performed to clean the samples. Mechanical and thermomechanical properties were evaluated in different environments to know the behavior of SiC through compression tests. The highest values were obtained at room temperature under normal conditions, a maximum stress of 686 MPa was achieved. In all cases, the samples had a fragile behavior as expected. In thermomechanical tests it was observed that resis...
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artículo
Geopolymers are a class of inorganic synthetic materials that in recent years have received extensive interest of the scientific community, mainly due to the variety of applications in which they can be used. The synthesis of these materials is based on a chemical process called geopolymerization, which consists of the alkaline activation of amorphous alumina and silica oxides present in many natural raw materials and industrial solid waste. Therefore, the present work proposes the use of inorganic mining residues (mine tailings) from gold mining in the southern region of Peru, for the manufacture of geopolymeric concrete. The first part of the research focused on the physical, structural and microstructural characterization of the raw material (fine sand and mining tailings), then the volumetric matrix of mixtures for five types of geopolymer concrete was determined. Cylindrical samples...
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artículo
Geopolymeric materials have recently been considered a revolutionary class of materials, due to the diversity of applications where they can be used, this derived from their good mechanical resistance, thermochemical stability and good fire resistance. From 1970 to the present, a notable increase has been observed in the number of scientific publications dealing with the synthesis and applications of geopolymeric materials with industrial application. Several publications have reported geopolymers as alternative materials to Portland cement, which will allow having a green construction industry in the coming years. The elaboration of geopolymeric materials is relatively simple, beginning with the identification of a source rich in amorphous aluminosilicates and a hardening compound (mainly alkaline in nature) which are properly mixed until a homogeneous and workable paste is obtained, th...
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artículo
Biomorphic SiC/Si compounds were fabricated from copaiba wood (Copaifera officinalis, natural wood native to Peru), by reactive infiltration of molten silicon in a porous carbon preform obtained by a controlled pyrolysis process of wood. Structural and microstructural characterization tests by X-ray diffraction and scanning electron microscopy, respectively, revealed, on the one hand, the presence of crystalline phases of SiC, Si and C, and on the other, the typical morphology of this type of material, which it consists of a continuous SiC scaffold with elongated channels in the direction of tree growth and the presence of residual Si and C located mainly in the porosities of the material. The mechanical behavior in uniaxial compression was also studied at a constant compression rate of 0.05 mm/min and as a function of temperature (from ambient to 1400 ºC) and test atmosphere (ambient a...