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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento de formula??es para produ??o de gr?s porcelanato a partir de mat?rias-primas da regi?o da bacia do Parna?ba

Luz, Jota Carlos 04 July 2008 (has links)
Made available in DSpace on 2014-12-17T14:06:46Z (GMT). No. of bitstreams: 1 JotaCL.pdf: 1574556 bytes, checksum: 2868fab9c273e6f4d25ecd9b2e4ba1b6 (MD5) Previous issue date: 2008-07-04 / Brazil is a great ceramic raw materials productor because of the its big number of clay deposits, in various areas of the ceramic industry. Although, the majority of the natural reservations are unknown or not studied yet, so there is no scientific technical dates that can guide their usage and industrial application, as well as the racional and optimazed way of usage by the industrial sector. The state of Maranh?o has a gigant mineral wealth as esmectite, bentonite, kaolin, clays, feldspates, marine salt, iron and others, but produce only products with small agregated value compared to the porcelanato, one of the most expensives ceramic cover tiles, the reason for that is the low water absorption (lower than 0,5%), beside present amazing tecnicals features, like mechanical resistence. The main objective of the work is to do the characterization of four clays, with the finallity of find an application by the results and develop formulations to produce porcelanato using these raw materials from Timon-MA. For this were made the raw materials characterization using X ray fluorecence; X ray diffraction; Differencial thermal analysis; Dilatometric analysis and Tecnological properties, planing three formulations that were sinterized at six different temperatures: 1150, 1170, 1190, 1210, 1230 and 1250?C for 7 minutes. After the sinteratization, the samples were submitted to tension resistance analysis. Were attained two formulations with the requested properties to produce porcelanato / O Brasil ? um grande produtor de mat?rias-primas cer?micas, em virtude do grande n?mero de jazidas de argilas que possui, nas diversas ?reas da ind?stria cer?mica. Todavia, a grande maioria destas reservas naturais ? desconhecida ou permanece indevidamente estudada, n?o havendo assim dados t?cnico-cient?ficos que orientem sua utiliza??o e aplica??o industrial, bem como sua utiliza??o de maneira mais racional e otimizada por parte do setor industrial. O maranh?o possui grandes riquezas minerais como esmectita, bentonita, caulim, argilas, feldspatos, micas, min?rio de ferro, talco, sal marinho, entre outras, no entanto produz apenas produtos de baixo valor agregado em rela??o ao gr?s porcelanato, uma das mais nobres cer?micas de revestimento, devido a sua baixa absor??o de ?gua (tipicamente abaixo de 0,5%), al?m de apresentar excelentes caracter?sticas t?cnicas, destacando-se resist?ncia mec?nica, ao risco e ao manchamento. Assim, o objetivo principal deste trabalho ? caracterizar quatro argilas, com a proposta final de uma aplica??o atrav?s dos resultados obtidos em laborat?rios e desenvolver formula??es para produ??o de gr?s porcelanato a partir de mat?rias-primas da regi?o de Timon-MA. Para isso, foi feita a caracteriza??o das mat?rias-primas por Fluoresc?ncia de Raios X; Difra??o de Raios X; An?lise t?rmica Diferencial; An?lise T?rmica Diferencial, An?lise Dilatom?trica e Propriedades Tecnol?gicas, elaborando tr?s formula??es que foram queimadas em seis temperaturas: 1150, 1170,1190 1210, 1230 e 1250?C com 7 minutos de patamar. Ap?s a queima, os corpos-de-prova foram submetidos a ensaios f?sico-mec?nicos e tamb?m por Microscopia Eletr?nica de Varredura. Foram obtidos para duas formula??es propriedades compat?veis com as exigidas para o gr?s
2

An?lise da Conformidade e Caracteriza??o da Mat?ria- Prima Empregada na Fabrica??o de Blocos Cer?micos na Regi?o Metropolitana de Salvador

Couvignou, Eliana Mac?do 02 June 2007 (has links)
Made available in DSpace on 2014-12-17T14:57:38Z (GMT). No. of bitstreams: 1 ElianaMC.pdf: 1221443 bytes, checksum: c2ecaef1ae772fb4d8e14dd13d82d037 (MD5) Previous issue date: 2007-06-02 / The potential market of the metropolitan area of Salvador accounts for the estimated consumption of roughly 800 million horizontally perforated extruded clay bricks a year. The growing demand of consumers along with the competitiveness of the structural ceramic sector has driven forward a number of recent efforts and investments towards improving the quality of structural ceramics. In this scenario, the present study focused on sampling and evaluating the conformity of 8-hole horizontally perforated extruded clay bricks manufactured by different plants (A, B and C) in the metropolitan area of Salvador. In addition, representative clay and sandy-clay materials were collected from each plant and characterized by conventional physical, chemical and mineralogical techniques. Finally, experimental compositions designated as A, B and C, according to the source, were prepared by mixing different contents of the raw materials collected in the plants, fired at different temperatures and characterized. The results revealed a series of non conformities regarding ABNT guidelines. The characterization of raw materials revealed the presence of kaolinite and ilite in concentrations ranging from 64 to 90 wt.% along with free quartz (10 - 25%). The sandy-clay samples consisted basically of kaolinite. All raw materials depicted low contents of organics, amorphous constituents, alkaline oxides and feldspar. An analysis of the firing behavior of all different ceramic compositions revealed that the linear contraction of composition A was rather significant considering the temperature range evaluated, and it justifies the significant dimensional non conformity that was shown by bricks made with the ceramic A / O mercado potencial de cer?mica estrutural na regi?o metropolitana de Salvador ? respons?vel pelo consumo de mais de 800 milh?es de pe?as/ano. Com um com?rcio cada vez mais exigente e competitivo torna-se necess?rio que as ind?strias ceramistas invistam em a??es que visem aperfei?oar a qualidade de seus produtos. O objetivo desse estudo foi avaliar o ?ndice de conformidade de blocos cer?micos e caracterizar a mat?ria-prima. Foram empregadas as normas ABNT para an?lise de conformidade de blocos cer?micos em tr?s ind?strias (A, B e C) da Regi?o Metropolitana do Salvador, bem como t?cnicas para caracteriza??o qu?mica, f?sica e mec?nica das mat?rias-primas e formula??o e an?lise das massas. Com base nos resultados alcan?ados pode-se concluir que os blocos cer?micos fabricados pelas ind?strias pesquisadas n?o apresentam conformidade com as normas t?cnicas brasileiras. Os argilominerais encontrados nas mat?rias-primas estudadas (massas A, B e C) foram a caulinita e a ilita que ficaram entre 64 a 90% e o teor de quartzo livre entre 10 e 25%. Os arenosos s?o predominantemente argilas caulin?ticas. Os materiais caracterizados apresentaram baixa concentra??o de materiais amorfos, baixo teor de ?xidos alcalinos e, conseq?entemente, concentra??es muito baixas de feldspatos. A an?lise das curvas de gresifica??o das massas demonstra que a inclina??o da curva de retra??o linear ? mais acentuada para a massa A, na faixa de temperatura estudada, e justifica a significativa n?o conformidade dimensional verificada nos blocos produzidos pela cer?mica A
3

Obten??o de uma porcelana diel?trica a partir de mat?rias-primas do Rio Grande do Norte

Silva, Elialdo Chib?rio da 26 March 2010 (has links)
Made available in DSpace on 2014-12-17T14:07:04Z (GMT). No. of bitstreams: 1 ElialdoCS_TESE.pdf: 4625434 bytes, checksum: bec8d03e9004e11648c49c45f84ffe0f (MD5) Previous issue date: 2010-03-26 / Universidade Federal do Rio Grande do Norte / The dielectric porcelain is usually obtained by mixing various raw materials proportions and is used in the production of electronic equipment for various applications, from capacitors of high and low Power to insulators for low, medium, high and extra high voltage, which are used in distribution lines and transmission of electricity.This work was directed to the s tudy of technological properties of technic porcelain, made from raw materials extracted from pegmatites found in the regions of Serid? and the Alto Oeste of Rio Grande do Norte, which are made of kaolin, quartz and feldspar, abundant and high quality in these regions. The technic ceramics were obtained by mixing in appropriate levels, kaolin, feldspar, quartz and clay, the last item from a pottery in the city of Sao Gon?alo do Amarante, Rio Grande do Norte. During the development the following characterizations correlated to raw materials were made: laser particle sizing, x-ray diffraction, DTA and TG. The compositions studied were formed by uniaxial pressing at a pressure of 50 MPa and sintered at temperatures ranging from 1150 to 1350?C and levels (times) of sintering between 30, 60, 90 and 120 minutes. The characterization of the samples were taken from the analysis of weight loss, linear shrinkage, porosity, stoneware curve, bulk density, flexural strength of three points, SEM and X-ray diffraction, TMA, Dielectric and cross Resistivity. The studied materials can be employed in producing the objects used in electrical engineering such as: insulators for low, medium and high-voltage electrical systems, command devices, bushing insulation for transformers, power capacitors, spark plugs, receptacles for fluorescent and incandescent light bulbs and others / A porcelana diel?trica ? normalmente obtida atrav?s da mistura de diferentes mat?rias-primas, em propor??es adequadas, sendo utilizada na produ??o de equipamentos eletroeletr?nicos de diversas aplica??es, desde capacitores de alta e baixa pot?ncia, a isoladores para baixa, m?dia, alta e extra alta tens?o, que s?o utilizados em linhas de distribui??o e transmiss?o de energia el?trica. Neste trabalho, s?o estudadas as propriedades tecnol?gicas de uma porcelana diel?trica, formulada a partir de mat?rias-primas obtidas de pegmatitos encontrados nas regi?es do Serid? e do Alto Oeste do Rio Grande do Norte, sendo estas constitu?das de caulim, quartzo e feldspato, abundantes e de alta qualidade nestas regi?es, e de uma argila proveniente de uma cer?mica situada no munic?pio de S?o Gon?alo do Amarante, tamb?m no Estado do Rio Grande do Norte. As mat?rias-primas foram caracterizadas atrav?s de: granulometria a laser, difra??o de raios X, an?lise t?rmica diferencial e an?lise termogravim?trica. As amostras foram conformadas por prensagem uniaxial a uma press?o de 50 MPa, e sinterizadas ?s temperaturas de 1150, 1200, 1250, 1300 e 1350 ?C, com patamares de sinteriza??o de 30, 60, 90 e 120 minutos. Os ensaios tecnol?gicos realizados foram: an?lise da perda de massa, retra??o linear, porosidade, curva de gressifica??o, microscopia eletr?nica de varredura, difra??o de raios X, dilatometria, rigidez diel?trica, resistividade transversal e permissividade diel?trica. Os melhores valores de propriedades foram obtidos na temperatura de 1250 ?C, para as composi??es estudadas, n?o sofrendo varia??es significativas em seu comportamento com o tempo de sinteriza??o. Os materiais estudados podem ser empregados na obten??o de objetos usados em eletrot?cnica como por exemplo: isoladores de baixa, m?dia e alta-tens?o para redes el?tricas, dispositivos de comando, bucha de isolamento de transformador, capacitores de pot?ncia, vela de igni??o, recept?culos de l?mpadas incandescentes e fluorescentes e outros
4

Estudo do efeito da substitui??o de caulim por res?duo de caulim na fabrica??o de cer?mica de revestimento / Effect of the replacement of kaolin by kaolin residue on the production of ceramic

Vieira, Jo?o Dantas Paiva 17 August 2007 (has links)
Made available in DSpace on 2014-12-17T14:57:47Z (GMT). No. of bitstreams: 1 JoaoDPV.pdf: 1303151 bytes, checksum: 407305d41d4b24852e57967eeba5cfd5 (MD5) Previous issue date: 2007-08-17 / Companies involved in kaolin mining and treatment represent an important area of industrial development in Brazil, significantly contribution to the worldwide production of such mineral. As a result, large volumes of kaolin residue are constantly generated and abandoned in the environment, negatively contributing to its preservation. In this scenario, the objective of the present study was to characterize the residue generated from kaolin mining as well as to assess its potential use as raw material for the production of ceramic tiles. Ceramic mixtures were prepared from raw materials characterized by X-ray fluorescence, X-ray diffraction, particle size analysis and thermal analysis. Three compositions were prepared using kaolin residue contents of 10%, 20% and 30%. Samples were uniaxially pressed, fired at 1200?C and characterized aiming at establishing their mineralogical composition, water absorption, apparent porosity, specific mass, linear retraction and modulus of rupture. The results showed that the residue basically consisted of kaolinite and successfully replaced raw kaolin in the preparation of ceramic title formulations without significantly affecting the properties of the fired material / As ind?strias de minera??o e beneficiamento de caulim s?o um importante segmento econ?mico do pa?s, com uma produ??o bastante significativa no cen?rio internacional. Em fun??o disso, a produ??o de res?duos ? muito grande, poluindo e agredindo o meio ambiente. Assim, esse trabalho tem por objetivo a caracteriza??o do res?duo do beneficiamento do caulim e a avalia??o de sua aplicabilidade como mat?riaprima alternativa na produ??o de cer?mica de revestimento. As mat?rias-primas utilizadas neste trabalho foram caracterizadas por t?cnicas de: fluoresc?ncia de raios X; difra??o de raios X; analise granulom?trica; an?lise termogravim?trica e an?lise termodiferencial. Foram formuladas tr? s composi??es contendo o res?duo de caulim, em propor??es de 10%, 20%, e 30%. Foram confeccionados corpos-de-prova por prensagem e suas massas foram queimadas a 1200?C e caracterizadas qu?mica e mineralogicamente com o objetivo de identificar suas composi??es, seus elementos e suas fases. Estes corpos-de-prova foram avaliados quanto ? absor??o de ?gua, porosidade aparente, massa espec?fica aparente, retra??o linear, difra??o de raios X e o m?dulo de ruptura ? flex?o. Pode-se concluir que o res?duo de caulim ? constitu?do basicamente por caulinita, e que a incorpora??o nas propor??es estudadas teve resultados altamente satisfat?rios nas formula??es, para a produ??o de cer?micas de revestimento
5

Produ??o de gr?s porcelanato a partir de mat?rias-primas do Rio Grande do Norte e queima a g?s natural / Production of porcelainized stoneware tiles from raw materials of the State of Rio Grande do Norte and burns the natural gas

Pinheiro, Andr?a Santos 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T14:57:51Z (GMT). No. of bitstreams: 1 AndreaSP.pdf: 1820286 bytes, checksum: a1263199151d8fb3f317fa86bacf6014 (MD5) Previous issue date: 2006-05-19 / The State of Rio Grande do Norte, Brazil, possess major deposits of feldspar, clay, kaolin and talc, all raw materials used in the production of porcelainized stoneware tiles. Conversely, state industries manufacture only low added value red ceramics. Porcelainized stoneware tiles is one of the noblest ceramics, depicting low water absorption (typically below of 0,5%), in addition to excellent staining resistance and mechanical strength. The present work aims at investigating the potential of local raw materials for the production of porcelainized stoneware tiles. To that end, these materials were characterized by X-ray fluorescence, X-ray diffraction, particle size analysis, thermal gravimetric analysis and thermal differential analysis. Admixtures containing different compositions were prepared and fired at three temperatures, 1150, 1200 and 1250?C for 30 min. After firing, tests samples were characterized by water absorption tests, linear retraction, dilatometric analysis, apparent porosity, apparent specific mass, flexural strength, and microstructural analysis by XRD and SEM. The results revealed that ceramics with porcelainized stoneware tiles characteristics could be produced from raw materials originated in the State of Rio Grande do Norte / O Rio Grande do Norte possui grandes jazidas de pegmatitos, argilas caulin?ticas e caulim, principais mat?rias-primas para a fabrica??o de gr?s porcelanato. No entanto, o RN produz apenas produtos de baixo valor agregado em rela??o ao porcelanato, uma das mais nobres cer?micas de revestimento, devido a sua baixa absor??o d??gua (tipicamente abaixo de 0,5%), al?m de apresentar excelentes caracter?sticas t?cnicas, destacando-se elevada resist?ncia mec?nica, ao risco e ao manchamento. O presente trabalho tem a finalidade de validar o potencial de mat?rias-primas do RN (feldspato, argila, caulim e talco beneficiado) para a produ??o de gr?s porcelanato. Para isso, foi feita a caracteriza??o das mat?rias primas por FRX, DRX, AG, ATG e ATD, elaborando-se cinco formula??es que foram queimadas em tr?s temperaturas: 1150, 1200 e 1250?C com 30 minutos de patamar. Ap?s a queima, os corpos-de-prova foram submetidos a ensaios de absor??o de ?gua, retra??o linear, porosidade aparente, massa espec?fica aparente, resist?ncia ? flex?o, DRX, MEV e an?lise dilatom?trica. Obteve-se para uma das misturas, propriedades compat?veis com as exigidas para um gr?s porcelanato
6

Produ??o de gr?s porcelanato a partir de mat?rias-primas do estado da Bahia

Brito, Jorge Ferreira 19 October 2009 (has links)
Made available in DSpace on 2014-12-17T14:57:53Z (GMT). No. of bitstreams: 1 JorgeFB.pdf: 2466045 bytes, checksum: 390a8dfd299d465779890586b1bd5be1 (MD5) Previous issue date: 2009-10-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The State Bahia, Brazil, presents different geological sites it with a very expressive variety minerals. It is situated among the very important States which produces minerals for industries, such as pointed aggregate, ornamentals stones and ceramics raw materials. Nowadays only four companies producting ceramics tiles. Porcelainized stoneware tiles is one of the noblest ceramics, depicting low water absorption (typically below of 0,5%), in addition to excellent staining resistance and mechanical strength. The present work aims at investigating the potential of local raw materials for the production of porcelainized stoneware tiles. For this purpose, these materials were characterized by X-ray fluorescence, X-ray diffraction, particle size analysis, thermal gravimetric analysis, thermal differential analysis and dilatometric analysis. Admixtures containing different compositions were prepared and fired at four temperatures, 1100 ?C, 1150 ?C, 1200 ?C and 1250 ?C with isotherm for 60 minute and heathing rate of 5 oC/min. After firing the samples, they were characterized by water absorption tests, linear retraction, analysis, apparent porosity, apparent specific mass, flexural strength, and microstructural analysis by X-ray diffraction and scanning electron microscopy . The results revealed three ceramics with porcelainized stoneware tiles characteristics and porcelain tile will be produce from raw materials originated in the State of Bahia / O Estado da Bahia apresenta uma diversidade de terrenos geol?gicos que encerra uma expressiva dota??o mineral e est? situado entre os mais importantes Estados produtores de minerais industriais, ressaltando-se agregados, rochas ornamentais e mat?rias-primas cer?micas. Atualmente somente quatro empresas produzem placas cer?micas. O gr?s porcelanato ? uma das mais nobres cer?micas de revestimento devido a sua baixa absor??o d ?gua (tipicamente abaixo de 0,5%), al?m de apresentar excelentes caracter?sticas t?cnicas, destacando-se pelas elevadas resist?ncias mec?nica, ao risco e ao manchamento. O presente trabalho tem a finalidade de avaliar o potencial das mat?rias-primas, feldspato, argila e caulim, utilizado na produ??o de gr?s porcelanato no estado da Bahia. Para isso, foi feita a caracteriza??o das mat?rias-primas por fluoresc?ncia de raios X (FRX), difra??o de raios X (DRX), an?lise granulom?trica (AG), an?lise t?rmica gravim?trica (TG), an?lise t?rmica diferencial (DTA) e an?lise dilatom?trica, elaborando-se sete formula??es que foram queimadas nas temperaturas: 1100 ?C, 1150 ?C, 1200 ?C e 1250 ?C, com isoterma de 60 minutos e taxa de aquecimento de 5 oC/ min. Ap?s a queima, os corpos-de-prova foram submetidos a ensaios de absor??o de ?gua, retra??o linear, an?lise dilatom?trica, porosidade aparente, massa espec?fica aparente, resist?ncia ? flex?o, difra??o de raios X e microscopia eletr?nica de varredura. Em tr?s formula??es foram obtidas, propriedades compat?veis com as exigidas para a produ??o do gr?s porcelanato com mat?rias-primas oriundas do Estado da Bahia
7

Estudo das vari?veis de processamento das mat?rias-primas da regi?o do crato - ce na fabrica??o de produtos cer?micos por extrus?o e por prensagem

Santos, Getulio de Moura 10 July 2010 (has links)
Made available in DSpace on 2014-12-17T14:57:55Z (GMT). No. of bitstreams: 1 GetulioMS.pdf: 1235965 bytes, checksum: 2c47ca0471a5470d046cd558e9c9cca4 (MD5) Previous issue date: 2010-07-10 / The limits to inform is about the character stico of basic, quimica, mineralogical and mechaniques of matlaughed material used in the manufacturing process the product certified in economic region the Cariri, specifically in the city of Crato, Cear? state, motivated the development of this work, since in this region the exist ing economic context that a general appear as important in the production chains. Were made twentyfive soils-test specimen collection and the study was performed to differentiate the mat laugh materials of variaveis processing of mathing raw materials in the factory The product mica monkeys by extrusion and pressing. The results were obtained ap s as analyzes: grain size, index of plasticity, fluoresce incidence X-ray difration the X-ray, and analyzes thermicals and properties technological. through s of curves gresifica returned to was a comparison between the retro the linear, absorb to water, porosity and bulk density. the results show that the excellent distribution and character acceptable available for the processing of the structure color dark red. needing, therefore, of the mixture of a less plastic clay with thick granulation, that works as plasticity reducer. In spite of the different resignation forms for prensagem and extrusion, the characteristics of absorption of water and rupture tension the flexing was shown inside of the patterns of ABNT / A limita??o de informa??es sobre as caracter?sticas f?sicas, qu?micas, mineral?gicas e mec?nicas da mat?ria-prima usada no processo de fabrica??o dos produtos cer?micos na regi?o do Cariri, mais precisamente na cidade do Crato, estado do Cear?, motivou o desenvolvimento deste trabalho, visto que nesta regi?o existem cer?micas que num contexto geral figuram como cadeias produtivas importantes no estado. Foram confeccionados vinte e cinco corpos-de-prova da amostra coletada para cada m?todo de conforma??o e foi realizado o estudo das vari?veis de processamento das mat?riasprimas na fabrica??o de produtos cer?micos por extrus?o e prensagem. Os resultados foram obtidos ap?s as an?lises de: granulometria, ?ndice de plasticidade, fluoresc?ncia de raios X, difra??o de raios X, an?lises t?rmicas e propriedades tecnol?gicas. Atrav?s das curvas de gresifica??o obteve-se um comparativo entre a retra??o linear de queima, absor??o de ?gua, porosidade e massa espec?fica aparente. Os resultados mostram que a mat?ria-prima tem excelente distribui??o e caracter?sticas aceit?veis para o processamento de pe?as estruturais de cor escura a vermelha, necessitando, pois, da mistura de uma argila menos pl?stica com granula??o grossa, que funciona como redutor de plasticidade. Apesar das diferentes formas de conforma??o por prensagem e extrus?o, as caracter?sticas de absor??o de ?gua e tens?o de ruptura a flex?o mostrou-se dentro dos padr?es da ABNT

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