Processamento e caracterização de compósito fibra de sisal/resina epóxi via RTM

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização de argilas usadas para produção de cerâmica vermelha e estudo das alterações nas suas propriedades pela adição de resíduos

Neste trabalho são apresentados os resultados de caracterização das principais argilas usadas pela indústria cerâmica vermelha regional e, também, de alguns resíduos sólidos produzidos na região de Presidente Prudente - SP. Os resultados da incorporação destes resíduos em massas cerâmicas são avaliados através do estudo de suas propriedades tecnológicas. Para a caracterização dos materiais foram utilizadas as seguintes técnicas: análise textural (concentração das frações areia, silte e argila), difratometria de raios X e análise térmica. As propriedades tecnológicas de corpos de prova cerâmicos foram avaliadas através dos seguintes parâmetros: retração linear (RL), perda de massa ao fogo (PF), massa específica aparente (MEA), porosidade aparente (PA), absorção de água (AA) e resistência mecânica à flexão (RMF). Corpos de prova, com diferentes concentrações de resíduos, foram prensados (prensa uniaxial manual) e queimados em temperaturas que variaram de 800 a 1200 oC, usando um forno tipo mufla com controle de temperatura. As argilas sedimentares foram coletadas nas margens do rio Paraná e em áreas de várzea, próximas as cerâmicas. As amostras estudadas, coletadas nos depósitos das cerâmicas, são usadas para produção de tijolos maciços, blocos furados e telhas. Quatro tipos diferentes de resíduos foram estudados: (1) lodo de estação de tratamento de água ETA, (2) torta de filtro de indústria de re-refino de óleo lubrificante, (3) pó de vidro (soda-cal) de garrafa tipo long neck descartável, e (4) cinza de bagaço de cana. Estes resíduos foram incorporados em massas cerâmicas coletadas nas indústrias... (Resumo completo, clicar acesso eletrônico abaixo)

Lean six sigma como estratégia para o aumento de eficiência em laminação de alumínio

This study aims to assess the implementation of Lean Six Sigma in the preparation of plates and hot lamination process for a company of aluminum rolled products, to improve the quality, productivity and process efficiency. As a basis for achieving these goals, the DMAIC methodology and various quality tools such as Cause Effect Diagram, Process Flow, SIPOC, Pareto, FMEA and Control Chart were used, trying to propose improvements to processes and increase their efficiency. The results were significant and were the basis for the continuation of a continuous improvement project throughout the factory

Remoção de cromo de resíduos de curtumes por argilitos da formação Corumbataí - SP

The tanning wastes are characterized to be significant sources of pollution in the hydrosphere when non adjusted or disposed adequated form. That happens because this industry type uses the chromium to tan hides, and this element is present in discharges concentrations in final wastes, characterizing this waste type as dangerous, according to the Associação Brasileira de Normas Técnicas, através da Norma Brasileira 10.004 de 2004. Due to this, the research proposes a form to reduction chromium of the tanning wastes through the process of adsorption. For that were used mining-wastes of Corumbataí Formation clays, material commonly used in the production of ceramic products in Rio Claro (SP). They were accomplished laboratory essays that involved the preparation of different clays pulps and subsequent mixture of these with the tanning wastes, maintaining them under different mixing times and adsorption contacts. After the separation of the mixtures, the leached were chemically analyzed and it was seen the efficiency of chromium reduction and your relationship with the variation of different times of contact clays/wastes and different grain sizes used in the pulps preparation.

Ensaios não destrutivos: metrologia e calibração

To perform the quality control of various industries like: petrochemical, nuclear, aerospace, steel, shipbuilding, pulp and paper, and inspection of welded products, castings, forgings, rolled products, among others, used the method of Non-Destructive Testing (NDT). The method is based on the physical properties of the material, so selecting a procedure more appropriate. The company Inter-Metro Serviços Especiais Ltda., with its cutting-edge laboratory, dedicated to the implementation of calibration services and measurement equipment for industrial, medical, occupational safety and Non-Destructive Testing (NDT). It has a trained team, providing guidance and providing support for improving procedures for testing and measuring

Fácies e associação de fácies da formação Pirambóia na região de Descalvado/SP

The Pirambóia Formation is a lithostratigraphic unit of the Paraná Basin, positioned between the Corumbataí (lower) and Botucatu (upper) Formations on the eastern edge of the basin. This unit is focused by many studies due to its great importance as an essential component in the Guarani Aquifer System (SAG) and the petroleum system “Irati-Pirambóia”, as excellent reservoirs. The Pirambóia Formation is historically the subject of several controversies on issues like age, contact relationships with the upper unit and depositional paleoenvironment. Despite these aspects, the Pirambóia Formation is commonly taken to be of Triassic age and is considered a product of wet aeolian systems, with plenty of wet interdunes and subordinate fluvial facies. In this work, by using techniques such as facies analysis, depositional architecture and facies association, facies of this unit were characterized and their depositional paleoenvironment was inferred particularly in Jundu Mining, region of Descalvado in northeastern São Paulo. Techniques such as grain size and petrographic analyses, aimed to characterize this unit as a potential reservoir rock. Five facies were described for the Pirambóia Formation in the studied region: St, Sh, Sm, Sr and Gt facies, generated by sedimentary processes of the bottom load type, mostly under low flow regime (with exception for the Sh facies, which is formed by upper flow regime processes). In addition to that, four facies associations were recognized from the architectural elements, primarily contained within the main channel: complex channel bars, composed by foreset macroforms (FM), sandy bedforms (SB) and gravel bars and bedforms (GB); flood deposits, constituted by laminated sand sheets (LS); deposits of hyperconcentrated flows and eolian deposits. It was interpreted that the Pirambóia Formation in Descalvado (SP) is the record of the sedimentation of braided rivers, with dunes and interdunes deposits...

Caracterização de compósitos produzidos por VARTM para aplicações aeronáuticas

In recent years the aeronautic industries has increased investment in areas of technological research aiming at materials that offer better performance, safety, weight reduction and fuel consumption. For this reason the most studied materials are polymeric materials, due to their higher mechanical strength and higher stiffness. This work evaluated characteristics of two composite laminates produced from the same process, but they differed only in regions where the resin was injected and the vacuum position. The composite laminates were SC-79 resin reinforced with glass fiber fabric (plain weave) processed via VARTM. For this reason the material was subjected to mechanical tests such as: tensile, and fatigue following standards ASTM D 3039 and ASTM D 3479, respectively. The latter was observed the S-N curve. It was performed the ultrassonic C-scan analysis to check impregnation of the fiber. Considering that the process was the same for the two laminates, with small variations in the injection and in vacum ports, it was expected to find similar characteristics

Analise dos esforços de laminação no dimensionamento de um laminador de bancada

The industry produces rolled, starting to and passing through casting forming processes, for example, in the case in question the rolling. A large portion of rolled products are flat, these have specific characteristics during their production and properties after finished that must be analyzed. For this a study of these properties must be made in materials samples, in order to be able to first know the material in question or provide new properties to the material through the process of rolling flat products. In this way is interesting that the students of mechanical engineering have knowledge of rolling trials, and from this can better understand the behavior of rolled. With this purpose the project of a benchtop rolling mill for the rolling of flat is needed, this work is the project of a sizing of one rolling mill non-ferrous materials

Avaliação do tempo e da concentração do condicionamento com ácido fluorídrico sobre a resistência de união entre cerâmica e cimento resinoso

The aim of this study was to verify through microtensile test the influence of time and concentration of surface conditioning with hydrofluoric acid and its interference in the adhesion of dual resin cement to porcelain.We used 32 bodies of glass-ceramic lithium disilicate system IPS e.max Press LT with dimensions of 6mm thick, 8 mm in length and 8 mm in length, which will be molded to obtain composite resin blocks corresponding to blocks ceramics. Ceramic and resin blocks were divided into 16 groups (n = 4) and numbered according to the concentration of hydrofluoric acid (2.5%, 5%, 7.5% and 10%) and conditioning time (20 seconds, 40 seconds, 1 minute and 2 minutes). The blocks were cleaned in ultrasonic apparatus with distilled water and dried with compressed air, subjected to acid etching and air-jet washed with water, dried with compressed air and received application of silane agent Monobond-S, followed by adhesive Excite ( Ivoclar Vivaden). Each ceramic block was bonded to the corresponding block of resin through the resin cement Multilink Automix. The specimens were cut to obtain nine micro samples for each set of ceramic-resin with 1 mm X 1 mm X 12 mm in length, which were submitted to microtensile test. The results were analyzed with descriptive statistics and analysis of variance with significance level of 5%, revealing that there were statistically significant (p = 0.000001 <0.05). From the Tukey test can be concluded that etching with hydrofluoric acid and 2.5% for 120 seconds gave the best bond strength, however, no statistical difference between the conditioning with the same acid in the concentration of 5.0% for 20 to 40 seconds

Vitrocerâmicas para blindagens balísticas

The use of ceramic materials in ballistic armor is considerable. Such materials can be very harder and lighter than metallic materials commonly used and it presents advantages to replace metallic materials when necessary toughness can be achieved. However, as SiC and Al2O3 ceramic, traditionally used for shielding, still have high manufacturing cost or low density do not have enough to shield applications such as aircraft. An alternative is the glass-ceramics, ceramics obtained by controlled crystallization of glasses, whose properties can be adjusted by choosing the chemical composition of glass, heat treatment of crystallization and special treatments such as ion exchange on the surface, resulting in increased mechanical strength . The objective of this project is to study the kinetics of crystallization of a glass composition based on cordierite (2MgO.2Al2O3.5SiO2), low density and high hardness, for the manufacture of glass-ceramics for ballistic tests. Shown in this report are results of heat treatment of crystallization and characterization by thermal analysis (DSC) glass obtained previously, indicating uneven distribution of crystals, and drying, weighing, mixing of raw materials and a new fusion of glass, the same composition

Considerações clínicas em implantes imediatos

The biological principles of osseointegration caused the rehabilitation treatment with osseointegrated implant become a safe, well alternative accepted by the dental community for the high success rate, allowing the preparation of functional and aesthetic prostheses in edentulous and partial patients. We passed the initial phase of functional vision for an aesthetic approach, too, depending on the demands of the patient and the quest for excellence by professionals. Over these last years, implant treatment has undergone many changes in surgical and prosthetic protocols. The less invasive surgical techniques and the development of restorative materials, especially ceramics allow the prosthetic rehabilitation of high functional quality and aesthetics. The installation of implants in sockets immediately after extraction of teeth involved by fracture, periodontal disease, endodontic lesions, is part of the arsenal of techniques for rehabilitating a number of advantages that we get to the outcome of multidisciplinary treatment. For this, we must consider several criteria in its planning as a fundamental unit, adjacent teeth, multiple losses, system, form and number of implants, type of retention of the prosthesis components, the patient expectation of the outcome perspective, gingival biotype, standard of ridge resorption, the smile line, etc. occlusal analysis. With the three-dimensional placement of the implant can immediately join the biological processes of repair of the socket, implant osseointegration, speeding treatment time. Much has been made by companies in the surface treatment of endosseous implants to be osseointegration shortened and restorative procedures started earlier, bringing benefits to the patient and professional. Among the main advantages we can emphasize the preservation of the structures adjacent to the teeth replaced, minor resorption of bone tissue involved... (Complete abstract click electronic access below)

Fácies, diagênese e arquitetura estratigráfica de reservatórios deltaico-lacustres da fase rifte (formação pendência), campo Serraria da Bacia Potiguar

Of the four lacustrine deltaic models, which were found in the Pendência formation, two are represented in the Serraria field. Respectively the deltaic models 1 and 3 shows the reservoir zones A and B. The Zone A is divided into six sub-areas. Each is representing a smaller cycle of development of sigmoidal lobes of deltaic front. Zone B produces in reservoirs of Model 3, or so called Full delta. The Zone B is formed by overlapping the deltaic plain system over the deltaic/prodeltaic front (model 1). This work uses the method of zooming with the aim to contextualize the geometric aspects of the sand bodies, highlighting the analysis of facies and diagenesis with help of pictures and testimonies of thin sections. The sigmoidal lobes of Zone A are fine to very fine sandstones, well sorted, with a arcosian composition.;practically with a weak compaction and cementation of a kind of film of clay (if very fine) and overgrowth feldspar (fine texture). This silicate phases are succeeded by cementation of poiquilotópica calcite, and after this a stage of dissolution, containing only regular permoporosity for this reservoir. Zone B has a combination of two types of deltaic plain reservoir. One is the rarest of distributary channel and the other the most common of lobes of crevasse. In the channel coarse to medium-grained and poor to moderate sorted sandstones are formed (tuning up), and with a lytic arcosiana nature. Rarely there are cements, including growth of feldspar and rhombohedral dolomite, which prevent a high permoporosity of the reservoir. In the crevasse lobes, the sandstones are laminated, fine and well sorted, arkosic, rarely with overgrowth feldspar and calcite poiquilotópica, and with a good intergranular permoporosity

Desempenho estrutural de vigas em madeira laminada colada armada

The objective of the present work was to evaluate Pinus’ glued laminated timber (glulam) beams and steel reinforced glulam beams, using PU mono-component adhesive in lamination step and epoxy adhesive to bond steel bars. The mechanical performance was verified through bending test, and the adopted method based on homogenized section, to considerate the differences between wood and steel mechanical properties. The homogenization section method proved itself effective in obtaining the stiffness of the parts in MLCA. The stiffness of reinforced beams increased 91% in comparison with glulam beams, differing only 5.5 % from value of stiffness calculated

Avaliação do efeito ambiental nas propriedades mecânicas e viscoelásticas de compósitos híbridos de titânio/fibra de carbono/resina epóxi

Hybrid composites combining metal plates and laminates with continuous fiber reinforced polymer, called fiber-metal (CHMF), have been particularly attractive for aerospace applications, due mainly to their high mechanical strength and stiffness associated with low density. These laminates (CHMF) consist of a sandwich structure consisting of layers of polymer composites and metal plates, stacked alternately. This setting allows you to combine the best mechanical performance of polymer composites reinforced with long fibers, to the high toughness of metals. Environmental effects should always be considered in the design of structural components, because these materials in applications are submitted to the effects of moisture in the atmosphere, the large cyclical variations of temperature around 82 ° C to -56 ° C, and high effort mechanical. The specimens of fibermetal composite were prepared at EMBRAER with titanium plates and laminates of carbon fiber/epoxy resin. This study aims to evaluate the effect of different environmental conditions (water immersion, hygrothermal chamber and thermal shock) of laminate hybrid titanium/carbon fiber/epoxy resin. The effects of conditioning were evaluated by interlaminar shear tests - ILSS, tensile, and vibration free

Estudo do comportamento térmico e reológico de amidos na conformação cerâmica de compostos multicamada com alumina, titanato de alumínio e dióxido de titânio

The project aims to develop ceramic compounds with gradients of the mechanical properties, using the molding technique with commercial starches. To understand the process of interaction between starch and ceramic powders, the proposed methodology involves viscometry tests (up to 200 °C). Viscometric assays were carried out with slurries of alumina, titania and aluminum titanate with potato starch, cassava and corn. The specimens were tested for dilatometry, thermomechanical, thermal shock, mechanical and characterization by SEM. The ceramic powders and starches were analyzed using the optical microscope to measure the size of these. It was made of th kinetics of starch gelatinization and titania with the cornstarch in theoptical microscope to observe how the grains of starch behaved in welling