28 documents found, page 1 of 3
Influence of pores on the failure of structural ceramic blocks
Villar, Carlos E.F.; Nogueira, Ricardo Emílio Ferreira Quevedo; Carvalho, Luis Alberto de Melo; Abreu, Hamilton Ferreira Gomes deThe main goal of this work is to investigate the features of pores of structural ceramic blocks which determine their process of failure under compression. Eighteen ceramic blocks were subjected to compression up to failure. Samples were removed from specific blocks according to the results of the compression tests in order to characterize their microstructure. Investigation of microstructure was carried out by...
Análise do processo de fraturamento em componentes de cimento Portland para apl...
Lima, Jeann Diniz Ferreira; Alves, Erisandra Rodrigues; Nogueira, Ricardo Emílio Ferreira Quevedo; Deus, Ênio Pontes deBecause of recent studies with order to use the cement as a material for application in endodontic treatment, in addition to it being one of the most used building materials in civil construction, for this wide range of applications, which are necessary degradation studies. For this study, using Portland cement, the specimens were prepared with the following measures 45 mm x 6.4 mm x 6.4 mm, and they have notch...
Análise numérica e experimental de propagação de trinca aplicada a biocimentos ...
Alves, Erisandra Rodrigues; Albuquerque, José Silvio Veras; Pennafort Junior, Luiz Carlos Gonçalves; Lima, Jeann Diniz FerreiraThe fracture toughness is an intrinsic property of the material, defined as the mechanical energy required to initiate and propagate a crack in the material until rupture occurs. In this property ceramics and bioceramics, in general, has very low values that can be explained by the existence of very small defects present in the material, which act as stress concentration factors. Calcium phosphate biocements ar...
Peças cerâmicas fabricadas usando pó de granito com adição dos produtos da comb...
Pinheiro, Halisson de Souza; Nogueira, Ricardo Emílio Ferreira Quevedo; Xavier, Louise Caroline Peixoto; Lobo, Cândido Jorge de SousaThe technical feasibility of the use of granite residues as raw material in the manufacture of ceramic test specimens, with additions of the Coal Mineral Combustion (PCC's) products as a reforestation phase, was studied. The materials used were White Wing granite (RGAB) and Coal Combustion Products (PCC), in concentrations of 0% w / w, 5% w / w, 10% w / w, 15% w / P of PCCs. For a characterization of the raw ma...
Caracterização das propriedades físicas e mecânicas de biocimentos de fosfato d...
Albuquerque, José Silvio Veras; Lourenço, Erisandra Rodrigues Alves; Lima, Jeann Diniz Ferreira; Nogueira, Ricardo Emílio Ferreira QuevedoThe biocimentos calcium phosphate are considered fragile and low mechanical properties, which can in the best cases equal the trabecular bone. The objective of this study was to evaluate the diametral compressive strength and porosity of biocimento combined with calcium sulfate dihydrate. The mechanical behavior and porosity of biocimentos were evaluated using samples shaped cylinder of 6 mm height and 12 mm di...
Biocimentos de fosfato de tricácio reforçados com sílica nanométrica
Lourenço, Erisandra Rodrigues Alves; Albuquerque, José Silvio Veras; Lima, Jeann Diniz Ferreira; Nogueira, Ricardo Emílio Ferreira QuevedoThe great advantage of biocimentos calcium phosphate is due to ease of handling and molding, maintaining the response bioactive and osteoconductive. The objective of this study was to obtain new formulations biocimentos by adding 5%, 10% and 15% by weight of silica nanometer. The samples were characterized by X-ray diffraction, infrared spectroscopy, Raman spectroscopy and bending test on three points. The XRD ...
Estudo sobre a utilização do rejeito de granito rosa Iracema como matéria-prima...
Lobo, Cândido Jorge de Sousa; Nogueira, Ricardo Emílio Ferreira Quevedo; Argonz, Raquel; Sasaki, José Marcos; Sales, Juscelino ChavesThe spinning navel is a component widely used in the textile industry. Such navels are basicaly alumina or high-alumina ceramic parts, and since they are not produced in Brazil, they are imported at high costs. For this reason, an alternative material for the fabricationof hte navel was proposed, consisting of granite powders.Since granites are basically silicates and exhibit lower mechanical strength and hardn...
Estudo sobre a utilização do rejeito de granito rosa Iracema como matéria-prima...
Lobo, Cândido Jorge de Sousa; Nogueira, Ricardo Emílio Ferreira Quevedo; Argonz, Raquel; Sasaki, José Marcos; Sales, Juscelino ChavesIn this work, physical properties of sintered compacts made from granite powder reinforced with alumina particles were determined. This composite is proposed as an economic alternative to the more expensive pure alumina, currently used in the fabrication of spinning navels for the textile industry. The composite material was compared to the materials from some spinning navels currently in use in a textile plant...
Síntese de mistura bifásica de fosfatos de cálcio via radiação por microondas
Duarte, Eden Batista; Nogueira, Ricardo Emílio Ferreira Quevedo; Silva, Cléber Cândido da; Albuquerque, José Silvio VerasSome of the calcium phosphates are classified as resorbable biomaterial that dissolve under certain physiological conditions. Hydroxyapatite (HÁ) and β-tricalcium phosphate (β-TCP) receive special attention for their large potential application as bone graft materials. They are chemically stable and have almost no adverse biological effects. In this study, apatite bioceramics were obtained from solid-state reac...
Estudo dos produtos da combustão do carvão mineral visando seu aproveitamento c...
Teixeira, Joelane Maria de Carvalho; Silva, Suely Alves; Pinheiro, Halisson de Souza; Nogueira, Ricardo Emílio Ferreira QuevedoThe process of combustion of mineral coal in power station generate waste or by-products (products of coal combustion, PCC's) potentially harmful to the environment. This study aims to identify us waste, the main chemical elements and all the major crystalline phases that contain them. The PCC's were milled in high energy mills and sintered at 1200 ° C for 2 hours. They were then submitted to characterization b...