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Determining the Emissivity of Roofing Samples: Asphalt, Ceramic and Coated CedarAdesanya, Oludamilola 12 1900 (has links)
The goal is to perform heat measurements examine of selected roofing material samples. Those roofing materials are asphalt shingles, ceramics, and cedar. It’s important to understand the concept of heat transfer, which consists of conduction, convection, and radiation. Research work was reviewed on different infrared devices to see which one would be suitable for conducting my experiment. In this experiment, the main focus was on a specific property of radiation. That property is the emissivity, which is the amount of heat a material is able to radiate compared to a blackbody. An infrared measuring device, such as the infrared camera was used to determine the emissivity of each sample by using a measurement formula consisting of certain equations. These equations account for the emissivity, transmittance of heat through the atmosphere and temperatures of the samples, atmosphere and background. The experiment verifies how reasonable the data is compared to values in the emissivity table. A blackbody method such as electrical black tape was applied to help generate the correct data. With this data obtained, the emissivity was examined to understand what factors and parameters affect this property of the materials. This experiment was conducted using a suitable heat source to heat up the material samples to high temperature. The measurements were taken during the experiment and displayed by the IR camera. The IR images show the behavior of surface temperatures being distributed throughout the different materials. The main challenge was to determine the most accurate emissivity values for all material samples. The results obtained by the IR camera were displayed in figures and tables at different distances, which was between the heap lamp and materials. The materials exhibited different behaviors in temperature and emissivity at certain distances. The emissivity of each material varied with different temperatures. The results led to suggestions of certain materials that could be beneficial and disadvantageous in energy and cost savings during cold and hot seasons of the year. Also this led to some uncertainties in the data generated. Overall, this can support in exploring other ideas to increase energy and cost saving consistently during both season by using a material that can change its color and density based on a high or low temperature.
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La céramique architecturale en Iran sous les Turkmènes Qarâ Qoyunlu et Âq Qoyunlu (c. 1450-1500) / Iranian tiles from the Turkman Qarâ Qoyunlu and Âq Qoyunlu’s dynasties (c. 1450-1500)Aube, Sandra 03 December 2010 (has links)
L’art des Turkmènes qarâ qoyunlu (782-873 h./1380-1468) et âq qoyunlu (780-914 h./1378-1508) alongtemps été dédaigné dans l’histoire de l’art du monde iranien. Pourquoi assimiler systématiquement cesoeuvres aux productions timourides ? Ne pourrait-on donc parler d’un « art turkmène » ? À partir d’un corpusde cinquante ensembles décoratifs en céramique, l’objectif de cette étude est de retracer une histoire desproductions turkmènes, de leurs formes, de leurs techniques, et d’en comprendre les articulations artistiques.L’ensemble des monuments qarâ qoyunlu et âq qoyunlu connus est dans un premier temps exploré,regroupés selon une présentation régionale : un parti pris permettant de souligner la force de traditionsartistiques locales autour de centres tels que Tabriz, E½fahân, Yazd ou encore Kâshân. Cette approche liminaireest suivie d’une analyse technique et ornementale des céramiques architecturales. Le dernier axe de cetterecherche s’intéresse à l’organisation de la production. L’enjeu est d’abord de comprendre les confluencesartistiques complexes s’exerçant alors en Iran, avant de s’arrêter sur les acteurs de cette production : lesmécènes et les artisans.Cette étude cherche à apporter un regard nouveau sur certains pans de la céramique architecturaleislamique. La « charnière turcomane » constitue en effet un jalon important de l’histoire de l’art : un point decontact avec les territoires timouride, mamlouk et ottoman frontaliers, et une passerelle vers les Empiresmodernes du siècle suivant. / Qarâ Qoyunlu (782-873 h./1380-1468) and Âq Qoyunlu (782-873 h./1380-1468) Turkman’s art haslong been disregarded in the art history of the Iranian world. This research brings the nature of Turkman art intoquestion, through the example of tiling art. Based on a group of fifty ornamental ceramic groups, this studyattempts to trace the history of Turkman decorative features, their designs, their techniques, and to understandtheir artistic connections.This research first proposes to explore every known qarâ qoyunlu and âq qoyunlu monument, sharedout among regional groups so that the strength of the regional traditions could be underlined around suchartistic centers as Tabriz, E½fahân, Yazd, or Kâshân. This part is followed by a technical and ornamental studyof Turkman tiles. The last component of that research is the organization of the production. It aims to givestatements about artistic confluences in Iran, and then to present actors of tiling production : the patrons andcraftsmen.This study intends to bring a new eye on some groups of Islamic tiles. The Turkman transition makesan important step in history of art: a meeting point between Timurid, Mamluk and Ottoman’s borderlineterritories, and a bridge to Modern Empires of the next century.
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La " faïence " dans les pavements médiévaux en France (XIIIe-XIVe s.) : approche technique, stylistique et symbolique du cas de Suscinio (c. 1330-1350) / Tin-glazed earthenware in French medieval floor-tiles (13th-14th centuries) : technical, stylistic and symbolic approach in the case of Suscinio (c. 1330-1350)Métreau, Laetitia 24 September 2012 (has links)
De son apparition dans les cours raffinées du lointain Orient islamisé à son exploitation industrielle en Occident, les procédés d’élaboration et les usages de la faïence ont évolué. En France, en l’état actuel des connaissances, l’introduction de cette technique remonte à l’époque gothique. Elle se manifeste alors de manière simultanée, dans des zones géographiques spécifiques, ponctuellement utilisée dans la composition de quelques luxueux pavements, où elle coexiste fréquemment avec des carreaux de terre cuite à glaçure transparente de tradition indigène. De tels pavements, parce qu’ils témoignent de la rencontre entre deux traditions techniques et culturelles, apparaissent comme des objets d’étude privilégiés pour appréhender conjointement les questions relatives à l’origine, la production et la consommation que pose la « faïence » à ses débuts en France. À partir de l’approche globale du cas de Suscinio, choisi en raison de son exemplarité, les chemins que cette technique exogène a empruntés et les raisons de son utilisation ont pu être précisés. Les données techniques, iconographiques et analytiques collectées grâce à la démarche méthodologique proposée apportent de nouveaux éléments de réponse. Ainsi, l’importation de produits finis et l’expérimentation locale ont pu être exclues au profit de l’importation de savoirs techniques ou du transfert de connaissances. Le répertoire iconographique et le style de tradition gothique ont montré qu’il y avait eu adaptation de la technique à un nouveau milieu socio-culturel. Son utilisation dans des lieux de l’édifice particuliers et particulièrement importants ne servait pas seulement une démonstration de pouvoir mais lui conférait également le statut de marqueur spatial, hiérarchique et social. / Tin-glazed earthenware manufacturing and use changed from its beginnings in the refined courts of the Islamic Far East up to its manufacturing in the West. In France, the technique was introduced during the Gothic period. It appears simultaneously, in specific geographical areas, at times used in the composition of luxurious floor-tiles where it often coexists with indigenous transparent high-lead glazed tiles. Such floor-tiles bear witness to the meeting between two technical and cultural traditions. That is the reason why they are particularly appropriate when studying together issues relating to the geographical origin, production and consumption of tin-glazed earthenware technique at its beginnings in France. The ways followed by this exogenous technique and the reasons for its use were clarified through the overall approach of the exemplary case of Suscinio. Technical, iconographical and analytical data collected by using a multidisciplinary methodology have provided some answers. Imported products and local experimentation can be excluded in favor of imported skills or transfer of knowledge. The Gothic tradition of the iconography and the style showed that the technique was adapted to a new socio-cultural context. Its use in particular and particularly important places was not only reserved to a manifestation of power but also worked as spatial, hierarchical and social markers.
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La céramique architecturale en Iran sous les Turkmènes Qarâ Qoyunlu et Âq Qoyunlu (c. 1450-1500) / Iranian tiles from the Turkman Qarâ Qoyunlu and Âq Qoyunlu’s dynasties (c. 1450-1500)Aube, Sandra 03 December 2010 (has links)
L’art des Turkmènes qarâ qoyunlu (782-873 h./1380-1468) et âq qoyunlu (780-914 h./1378-1508) alongtemps été dédaigné dans l’histoire de l’art du monde iranien. Pourquoi assimiler systématiquement cesoeuvres aux productions timourides ? Ne pourrait-on donc parler d’un « art turkmène » ? À partir d’un corpusde cinquante ensembles décoratifs en céramique, l’objectif de cette étude est de retracer une histoire desproductions turkmènes, de leurs formes, de leurs techniques, et d’en comprendre les articulations artistiques.L’ensemble des monuments qarâ qoyunlu et âq qoyunlu connus est dans un premier temps exploré,regroupés selon une présentation régionale : un parti pris permettant de souligner la force de traditionsartistiques locales autour de centres tels que Tabriz, E½fahân, Yazd ou encore Kâshân. Cette approche liminaireest suivie d’une analyse technique et ornementale des céramiques architecturales. Le dernier axe de cetterecherche s’intéresse à l’organisation de la production. L’enjeu est d’abord de comprendre les confluencesartistiques complexes s’exerçant alors en Iran, avant de s’arrêter sur les acteurs de cette production : lesmécènes et les artisans.Cette étude cherche à apporter un regard nouveau sur certains pans de la céramique architecturaleislamique. La « charnière turcomane » constitue en effet un jalon important de l’histoire de l’art : un point decontact avec les territoires timouride, mamlouk et ottoman frontaliers, et une passerelle vers les Empiresmodernes du siècle suivant. / Qarâ Qoyunlu (782-873 h./1380-1468) and Âq Qoyunlu (782-873 h./1380-1468) Turkman’s art haslong been disregarded in the art history of the Iranian world. This research brings the nature of Turkman art intoquestion, through the example of tiling art. Based on a group of fifty ornamental ceramic groups, this studyattempts to trace the history of Turkman decorative features, their designs, their techniques, and to understandtheir artistic connections.This research first proposes to explore every known qarâ qoyunlu and âq qoyunlu monument, sharedout among regional groups so that the strength of the regional traditions could be underlined around suchartistic centers as Tabriz, E½fahân, Yazd, or Kâshân. This part is followed by a technical and ornamental studyof Turkman tiles. The last component of that research is the organization of the production. It aims to givestatements about artistic confluences in Iran, and then to present actors of tiling production : the patrons andcraftsmen.This study intends to bring a new eye on some groups of Islamic tiles. The Turkman transition makesan important step in history of art: a meeting point between Timurid, Mamluk and Ottoman’s borderlineterritories, and a bridge to Modern Empires of the next century.
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O barro cinzento paulista: produção em barro cozido nas olarias do Tijucusú e de Pinheiros. Ordem de São Bento em São Paulo entre o século XVI e o XIX / The paulista grey clay: terracota production in Tijucusú and Pinheiros potteries. Saint Benedict\'s Order in São Paulo between the 16th and 19th centuriesVieira, Edileine Carvalho 08 November 2016 (has links)
A pesquisa pretende levantar através de documentação disponível, além de outras fontes, informações sobre as origens da produção em barro cozido nas olarias da Vila de Piratininga, ou como iremos tratá-la aqui, Vila de São Paulo, especialmente sob a administração da Ordem Beneditina, no período entre 1560 e 1870. Trataremos de identificar as técnicas de produção empregadas na elaboração das peças produzidas nestas olarias, como telhas, tijolos, louças, etc, sobretudo, nas olarias da Fazenda do Tijucusú pertencentes à Ordem Beneditina e na olaria da Vila de Pinheiros administrada pelos beneditinos. Investigaremos a documentação disponível sobre as olarias e pretendemos demonstrar as técnicas e as finalidades de uso das peças ali produzidas, assim como em outras olarias da Vila de São Paulo no período citado, na tentativa de confirmar a existência efetiva de uma indústria oleira consistente e uma mão de obra especializada. / The research intends to raise through available documentation, and other sources, information about the origins of production in terracota in the brick kilns of Piratininga village or how we treat it, Vila Sao Paulo, especially in the administration of the Benedictine\"s Order in the period between 1560 and 1870. We will try to identify the production techniques used in the preparation of the pieces produced in these brick kilns, such as tiles, bricks, crockery, etc., and especially the potteries of Tijucusú Treasury belonging to the Benedictine Order and the pottery of Pine Village run by the Benedictines. We investigate the available documentation on these potteries and we intend to demonstrate the techniques and the use purposes of there produced parts, as well as in other potteries from the town of São Paulo in the period mentioned in an attempt to confirm the actual existence of a consistent potter industry and a skilled labor.
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Αξιοποίηση της Ερυθράς Ιλύος στη βιομηχανία παραδοσιακών κεραμικών / Utilisation of Red Mud in the heavy clay industryΠοντίκης, Ιωάννης 05 November 2007 (has links)
Στην παρούσα Διατριβή παρουσιάζεται η μελέτη της δυνατότητας αξιοποίησης της ερυθράς ιλύος, ΕΙ, η οποία παράγεται κατά τη διαδικασία παραγωγής της αλουμίνας με τη διεργασία Bayer, για την παραγωγή δομικών παραδοσιακών κεραμικών, κύρια τούβλων και κεραμιδιών. Μελετήθηκαν αργιλούχα μίγματα με ΕΙ για ποσοστά ΕΙ από 10%κβ έως και 100%κβ.Επιγραμματικά, για την ΕΙ, πραγματοποιήθηκε χαρακτηρισμός και μελέτη της θερμικής συμπεριφοράς της. Για τα μίγματα της ΕΙ με αργιλούχες Α' ύλες, πραγματοποιήθηκε θεωρητικός σχεδιασμός τους, ενώ μελετήθηκε η επίδραση των σταδίων ανάμιξης και λειοτρίβησης, η επίδραση της ΕΙ στην πλαστικότητα, η θερμική συμπεριφορά, οι φυσικομηχανικές ιδιότητες των τελικών κεραμικών, η επίδραση της θερμοκρασίας και ατμόσφαιρας όπτησης καθώς και η περιβαλλοντική τους συμπεριφορά. Πραγματοποιήθηκαν επιπρόσθετα πιλοτικές δοκιμές παραγωγής τούβλων και κεραμιδιών. Τα αποτελέσματα της διατριβής, οδήγησαν στην ανάπτυξη μιας βέλτιστης διεργασίας παραγωγής κεραμικών με ΕΙ, η οποία αφορά στο σχεδιασμό του μίγματος με ΕΙ και την όπτησή του σε αναγωγικές συνθήκες. / In the present thesis, Bayer's process red mud, RM, is being studied as an additive and raw material for the production of heavy clay ceramics, mainly bricks and roofing tiles. A number of clay mixtures with RM were studied, for a RM content ranging from 10wt% to 100wt%. In summary, RM was characterised and studied for its thermal behaviour whereas, for the clay mixtures with RM, their design is provided, and the effect of comminution steps, the effect of RM on plasticity, their thermal behaviour, the influence of firing temperature and atmosphere, the physicomechanical properties of the end bodies, as well as their environmental behaviour are studied. In addition, pilot plan scale experiments were performed for the production of bricks and roofing tiles. The results of this thesis, led to the development of an optimised process for the production of ceramics with RM, which emphasises on the design of the body mixture as well as on the firing in reducing conditions.
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Coral recruitment on a high-latitude reef at Sodwana Bay, South Africa : research methods and dynamics.Hart, Justin R. January 2011 (has links)
Coral recruitment is a key process that contributes to the community structure and resilience of coral
reefs. As such, quantification of this process is important to assist with the management of these
threatened ecosystems. While coral recruitment has been the focus of numerous studies over the past
30 years, an understanding of this process on the high-latitude reefs of South Africa is limited. In
addition, variations in methods used in recruitment studies make the results difficult to compare. A
rapid in-situ method for universal application in the detection of early post-settled recruits would
thus be useful.
In this study, scleractinian coral recruitment was investigated at three study sites on Two-mile Reef,
over two six-month sampling periods, covering summer and winter. Two components were
investigated by attaching settlement tiles consisting of ceramic and marble tiles, and ceramic tiles
conditioned with crustose coralline algae (CCA) onto the reef in a spatially structured experimental
design. Firstly, coral recruitment was compared on the three different tile surfaces and fluorescence
photography was investigated as a rapid in situ technique to detect early post-settled recruits.
Fluorescence photography was then used to compare recruitment on tiles with the surrounding
natural substrata. Secondly, the spatial and temporal variation in the abundance, composition and
size of recruits was investigated. Additionally, the percentage cover of biota surrounding each recruit
within three millimeters of its corallum was visually estimated to quantify the microhabitat
surroundings of coral recruits.
Overall recruitment on the three tile types differed, yet spatial variation in coral recruitment,
regardless of tile surface, accounted for most of the variance in recruitment. While the highest
recruitment occurred on CCA tiles, this was not significantly greater than ceramic tiles, indicating
that the conditioning of ceramic tiles with Mesophyllum funafutiense CCA did not enhance coral
settlement in this study. Although many recruits were not detected with fluorescent photography
(73%), it proved useful to reveal recruits as small as 0.75 mm in corallum diameter, and indicated
that recruitment on the tiles and natural substratum differ significantly. Spatially, the abundance and
composition of coral recruits differed between study sites, within sites, and predominantly occurred
on tile edges. Coral recruitment was lowest at shallower sites, and was dominated by pocilloporids
regardless of study site. Additionally, the abundance and composition of recruits differed between
the two sampling periods, with a 6.6-fold decrease in the mean abundance of recruits from summer
to winter, with only pocilloporid settlement occurring in the latter season. The majority of recruits
were <3 mm, and their microhabitat was dominated by bare substrata and crustose coralline algae.
The results suggest that, while the choice of artificial settlement surface used in such studies can
have a profound influence on the results, spatial variation in recruitment can be greater. The recovery
of scleractinian coral taxa on Two-mile Reef in the event of a severe disturbance is expected to
differ, with greatest recovery in areas of high levels of recruitment. The microhabitat surrounding
recruits is described here for the first time, suggesting that further research into coral-crustose
coralline algae interactions is warranted. Finally, while fluorescence photography has its limitations,
it shows promise as a useful tool for rapid qualitative, but not quantitative, assessment of
recruitment. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2011.
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Efeito da adi??o de feldspato e/ou res?duo de caulin em formula??es ? base de argila il?ticaCastro, Raimundo Jos? de Sousa 16 November 2010 (has links)
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Previous issue date: 2010-11-16 / The red pottery industry in Piau? state is well developed and stands out at the
national context for the technical quality of its products. The floor and wall tile
industry, however, is little developed since the state has only one company that
produces red clay-based ceramic tiles. This thesis aims at using the predominantly
illitic basic mass of the above mentioned industry, with the addition of feldspar and/or
kaolin residue in order to obtain products of higher technical quality. Kaolin residue
consists basically of kaolinite, muscovite mica and quartz; the feldspar used was
potassic. In this experiment, basic mass (MB) was used for experimental control and
fifteen formulations codified as follows: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16,
FR32, R2, R4, R8, R16 and R32. All raw materials were dry-milled, classified,
formulated and then humidified to 10% water. Thereafter, test samples were
produced by unixial pressing process in a rectangular steel matrix (60.0 x 20.0 x 5.0)
mm3 at (25 MPa). They were fired at four temperatures: 1080?C, 1120?C, 1160?C,
with a heating rate of 10?C/min during up to 10 min in an electric oven, and the last
one in an industrial oven with a peak of 1140?C, aim ing to confirm the results found
in laboratory and, finally, technological tests were performed: MEA, RL, AA, PA, TRF
and PF. The results revealed that the residue under study can be considered a raw
material with large potential in the industry of red clay-based ceramic tiles, since the
results found both in laboratory and in the industry have shown that the test samples
produced from the formulations with up to 4% feldspar and those produced with up to
8% feldspar and residue permitted a reduction in the water absorption rate and an
increase in the mechanical resistance while those samples produced with up to 4%
residue had an increase in the mechanical resistance when compared to those
produced from the basic mass and that the formulation with 2% feldspar and residue
presented the best technological properties, lowering the sintering temperature down
to 1120?C / A ind?stria de cer?mica vermelha do Piau? ? bem desenvolvida e se destaca no
contexto nacional pela qualidade t?cnica de seus produtos. J? a ind?stria de
revestimento pouco se desenvolveu, visto que o estado possui uma ?nica empresa
que produz revestimento de base argilosa vermelha. Esta tese tem por objetivo
utilizar a massa b?sica predominantemente il?tica da ind?stria citada, adicionando ?
mesma feldspato e/ou res?duo de caulim com o prop?sito de obter produtos de
melhores qualidades t?cnicas. O res?duo caulim ? constitu?do basicamente de
caulinita, mica moscovita e quartzo; o feldspato utilizado foi o pot?ssico. Para este
experimento, utilizou-se a massa b?sica (MB) para controle experimental e quinze
formula??es assim codificadas: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16, FR32,
R2, R4, R8, R16 e R32. Todas as mat?rias-primas foram mo?das a seco,
caracterizadas, formuladas, depois umidificadas a 10% com ?gua. Em seguida,
foram confeccionados corpos-de-prova por prensagem uniaxial em matriz retangular
de a?o (60,0 x 20,0 x 5,0) mm? a (24 MPa), os quais foram queimados em quatro
temperaturas: 1080?C, 1120?C, 1160?C, com taxa de aqu ecimento de 10?C/min e
patamar de 10 min em forno el?trico, e a ?ltima em forno a rolo industrial e pico de
1140?C com o objetivo de validar os resultados encontra dos em laborat?rio; por
?ltimo, foram realizados ensaios tecnol?gicos: MEA, RL, AA, PA, TRF e PF. Os
mesmos mostraram que o res?duo estudado pode ser considerado como mat?riaprima
de grande potencial para a ind?stria de pisos e revestimentos cer?micos de
base argilosa vermelha, j? que tanto os resultados encontrados em laborat?rio como
na ind?stria mostram que os corpos-de-prova produzidos a partir das formula??es
com feldspato at? 4% e os produzidos com feldspato e res?duo at? 8% permitiram
uma redu??o da absor??o de ?gua e aumento da resist?ncia mec?nica, sendo que
os corpos-de-prova produzidos com at? 4% de res?duo tiveram aumento da
resist?ncia mec?nica, quando comparados aos corpos-de-prova produzidos a partir
da massa b?sica e que a formula??o com 2% de feldspato e res?duo apresentou
melhores propriedades tecnol?gicas, reduzindo a temperatura de sinteriza??o para
1120?C
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Uso de res?duo e de minerais de pegmatito da regi?o do serid? RN e de argilas portuguesas em formula??es de gr?s porcelanatoSilveira, Gleba Coelli Luna da 20 December 2010 (has links)
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Previous issue date: 2010-12-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In the State Rio Grande do Norte, Brazil, the most significant deposits of minerals in the production of granite and pegmatite are Serid? region. Municipalities of Parelhas and Equador are the main responsible for the production of feldspar, quartz, kaolin and granite. The ceramic industries are always in search of competitiveness by investing in new products or improving existing techniques. The stoneware is a type of pottery that stands in the market because it presents technical and aesthetic characteristics superior to other existing products. Characteristics of the raw materials initially obtained with chemical analysis and mineralogical analysis are crucial in getting a product that satisfies the conditions in a manufacturing process and is, in principle, directly related to the firing cycle. This research aimed at developing new formulations for the mass production of ceramic stoneware. The raw materials initially characterized were feldspar, quartz, kaolin and granite. As part of the research was developed at the University of Aveiro, in Portugal, we used two clays used in the production of Portuguese ceramics. The raw material Brazilian and Portuguese and the final product, both in Portugal and Brazil, were analyzed for X-ray fluorescence, X-ray diffraction, granulometric analysis, dilatometric analysis, thermal analysis and analysis of scanning electron microscopy (MEV). The specimens prepared at the University of Aveiro (DECV) were sintered at 10000C and 12000C and the specimens prepared in UFRN were sintered at 10000C, 10500C, 11000C, 11500C, 12000C, 12500C and 13000C, but the best results and demonstrating the presence of the mineral mullite were at temperatures of 12000C, 12500C and 13000C. The results showed that the granite waste used may be considered raw material of excellent quality for use in the ceramic industry and coating floors and more accurately by the industry of stoneware. Physical and mechanical tests conducted on samples of the formulations F01 and F02 developed in UFRN showed a water absorption and mechanical strength suitable for the stoneware / No estado do Rio Grande do Norte, Brasil, as jazidas mais expressivas na produ??o de minerais de pegmatito e granito est?o na regi?o do Serid?. Os munic?pios de Parelhas e Equador s?o os principais respons?veis pela produ??o de feldspato, quartzo caulim e granito. As ind?strias cer?micas est?o sempre em busca de competitividade, investindo em novos produtos e/ou aprimorando as t?cnicas existentes. O gr?s porcelanato ? um tipo de cer?mica que se destaca no mercado, pois apresenta caracter?sticas t?cnicas e est?ticas superiores a de outros produtos existentes. As caracter?sticas das mat?rias-primas obtidas inicialmente com a an?lise qu?mica e a an?lise mineral?gica s?o decisivas para que se obtenha um produto com as condi??es que satisfa?a a um processo de fabrica??o estando, a princ?pio, diretamente relacionados com o ciclo de queima. Esta pesquisa teve como objetivo o desenvolvimento de novas formula??es de massas cer?micas para a produ??o de gr?s porcelanato. As mat?rias-primas caracterizadas inicialmente foram o feldspato, o quartzo, o caulim e o granito. Como parte da pesquisa foi desenvolvida na Universidade de Aveiro, em Portugal, foram usadas duas argilas empregadas na produ??o de cer?micas portuguesas. A mat?ria-prima brasileira e portuguesa e o produto final, tanto em Portugal como no Brasil, foram submetidos ?s an?lises de fluoresc?ncia de raios-X, difra??o de raios-X, an?lise granulom?trica, an?lise dilatom?trica, an?lises t?rmicas e an?lises de microscopia eletr?nica de varredura. Os corpos de prova preparados na Universidade de Aveiro (DECV) foram sinterizados a 1000 ?C e 1200 ?C e os corpos de prova preparados na UFRN foram sinterizados a 1000 ?C, 1050 ?C, 1100 ?C, 1150 ?C, 1200 ?C, 1250 ?C e 1300 ?C, por?m os melhores resultados obtidos e que evidenciaram a presen?a do mineral mulita foram nas temperaturas de 1200 ?C, 1250 ?C e 1300 ?C. Os resultados mostraram que o res?duo de granito usado pode ser considerado mat?ria-prima de excelente qualidade para uso na ind?stria cer?mica de pisos e revestimento e mais exatamente pela ind?stria de gr?s porcelanato. Os ensaios f?sicos e mec?nicos realizados nos corpos de prova das formula??es 01 e 02 desenvolvidas na UFRN apresentaram uma absor??o de ?gua e resist?ncia mec?nica pr?prias para o gr?s
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Adi??o de subprodutos da cinza da casca de caf? (coffea canephora) em massa cer?mica para porcelanatoDultra, Eduardo Jorge Vidal 23 May 2013 (has links)
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Previous issue date: 2013-05-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / To produce porcelain tiles fluxing agents are used in order to obtain a liquid phase
during firing. This liquid phase fills the pores decreasing porosity, water absorption
and contributes to material densification. In the porcelain tiles industry, feldspar is the
main flux material used, with quantities ranging between 35 and 50%. Studies focus
on the discovery of materials with flux characteristics that can reduce the
consumption of feldspar by porcelain tiles industry. In this context, the coffee husk
ashes, a residue obtained when coffee husks are burned to produce heat for the
dryers during the processing of the green fruit, have as main chemical constituents
potassium, calcium and magnesium, giving them characteristics of fluxing material.
Brazil is the largest coffee producer in the world and is responsible for over 30% of
the world s production. In this work a physical treatment of coffee husk ash was
carried out in order to eliminate the organic matter and, after this, two by-products
were obtained: residual wastes R1 and R2. Both residues were added separately as
single fluxes and also in association with feldspar in mixtures with raw materials
collected in a porcelain industry located in Dias d ?vila-Ba. The addition of these
residues aimed to contribute to the reduction of the consumption of feldspar in the
production of porcelain tiles. Specimens were produced with dimensions of 60 mm x
20 mm x 6 mm in an uniaxial die with compacting pressure of 45 MPa. The samples
were heated to a temperature of 1200 ?C, for 8 minutes. Tests were performed to
characterize the raw materials by XRF, XRD, particle size analysis, DTA and TGA
and, additionally, the results of the physical properties of water absorption, apparent
porosity, linear shrinkage, density, dilatometry, flexural strength and SEM of sintered
body were analyzed. Additions of less than 8% of the residue R1 contributed to the
decrease of porosity, but the mechanical strength of the samples was not
satisfactory. Additions of 5% the R2 residue contributed significantly to decrease the
water absorption and apparent porosity, and also to increase the mechanical
strength. Samples with addition of feldspar associated with the R2 residue, in
proportions of 6.7% of R2 and 6.7% of feldspar, led to results of water absorption of
0.12% and mechanical strength of 46 MPa, having parameters normalized to the
manufacture of porcelain stoneware tiles / Na fabrica??o de porcelanatos s?o utilizados fundentes com a finalidade de obter
fase l?quida durante a queima que, por sua vez, preenche os poros diminuindo a
porosidade, a absor??o de ?gua, e contribui para a densifica??o do material. Na
ind?stria de porcelanatos o feldspato ? o principal material fundente utilizado, com
percentuais que variam entre 35 e 50% em massa. Pesquisas s?o direcionadas para
a descoberta de materiais com caracter?sticas fundentes que possam diminuir o
consumo de feldspato. Nesse contexto, a cinza da casca de caf?, res?duo obtido
quando cascas de caf? s?o queimadas a fim de produzir calor para os secadores
mec?nicos durante o beneficiamento do fruto, possuem como principais elementos o
pot?ssio, c?lcio e magn?sio, conferindo-lhe caracter?sticas de material fundente. O
Brasil ? o maior produtor de caf? do mundo, respons?vel por mais de 30% da
produ??o mundial. Nesse trabalho, foi realizado um tratamento f?sico na cinza de
caf? com a finalidade de eliminar parte do material carbonizado e, ap?s este, foram
obtidos dois subprodutos: res?duo R1 e res?duo R2. Ambos os res?duos foram
adicionados, separadamente, como ?nicos fundentes, e tamb?m associados ao
feldspato, em massas com mat?rias primas coletadas em uma f?brica de
porcelanatos localizada no munic?pio de Dias d ?vila-Ba. A adi??o desses res?duos
teve o objetivo de verificar a possibilidade de reduzir o consumo de feldspato na
produ??o de porcelanatos. Foram confeccionados corpos de prova com dimens?es
de 60 mm x 20 mm x 6 mm em matriz uniaxial, com press?o de compacta??o de 45
MPa. Os corpos de prova foram sinterizados na temperatura de 1200 ?C com
patamar de 8 minutos. Foram realizados ensaios para caracteriza??o das mat?riasprimas
por FRX, DRX, AG, ATD e ATG, e analisados os resultados das propriedades
f?sicas de absor??o de ?gua, porosidade aparente, retra??o linear, MEA, an?lise
dilatom?trica, resist?ncia ? flex?o e MEV do corpo sinterizado. A adi??o de at? 8%
do res?duo R1 contribuiu para a diminui??o da porosidade aparente, por?m a
resist?ncia mec?nica das amostras n?o foi satisfat?ria. A adi??o de 5% de res?duo
R2 contribuiu significativamente para diminuir absor??o de ?gua e porosidade
aparente, e tamb?m, para o aumento da resist?ncia mec?nica ? flex?o. As amostras
com adi??o do res?duo R2 associado ao feldspato, nas propor??es de 6,7% de R2 e
6,7% de feldspato, obtiveram resultados de absor??o de ?gua de 0,12% e
resist?ncia mec?nica ? flex?o de 46 MPa, atendendo aos par?metros normalizados
para fabrica??o de porcelanatos
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