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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

Estudo de um material comp?sito de poliuretano e res?duo de pneu direcionado ? fabrica??o de absorvedores de para-choque automotivo

Cavalcante, Amanda Gon?alves 21 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-02T23:44:17Z No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-09T20:53:35Z (GMT) No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) / Made available in DSpace on 2017-10-09T20:53:35Z (GMT). No. of bitstreams: 1 AmandaGoncalvesCavalcante_DISSERT.pdf: 2863796 bytes, checksum: fb2416c18becb76bd35ed0b21f5cd0e2 (MD5) Previous issue date: 2017-07-21 / O descarte de pneus no meio ambiente na forma de res?duo vem causando grandes problemas e impactos ambientais. Sendo assim, este trabalho apresenta a obten??o e estudo da caracteriza??o de um material comp?sito, voltado para a fabrica??o de um absorvedor de impacto de para-choque automotivo. Esse material foi fabricado com resina matriz de poliuretano (PU) ? base de petr?leo e carga de res?duos de pneu, oriundos do processo de recauchutagem. Para tanto, cinco formula??es com diferentes percentuais de res?duo de pneu (0%, 30%, 45%, 70% e 100%) foram obtidas e caracterizadas no que se refere ?s suas propriedades mec?nicas, t?rmicas, de absor??o de umidade, densidade e degrada??o pela sua exposi??o ?s intemp?ries. Al?m disso, foram realizados os ensaio de Microscopia Eletr?nica de Varredura (MEV) e Espectroscopia de Energia Dispersiva (EDS) no material para que se pudesse observar sua microestrutura (distribui??o de res?duos na matriz, vazios, imperfei??es e impurezas) e identificar os elementos qu?micos presentes, respectivamente. Como resultado geral, os comp?sitos apresentaram um aumento na sua densidade conforme se aumentava o percentual de res?duo de pneu, assim como a condutividade t?rmica. Quanto ?s propriedades mec?nicas, a formula??o que teve maior resist?ncia ? tra??o, flex?o e compress?o foi a de 45% e a de maior resist?ncia ao impacto foi a de 100%. Com rela??o ? resist?ncia ao envelhecimento a formula??o de 100% foi a que obteve melhor desempenho. Foi fabricado um absorvedor de para-choque com a formula??o de 45% que apresentou um acr?scimo de massa de 28,03%, demonstrando-se a viabilidade de fabrica??o desse componente automotivo. / The disposal of tires in the environment in the form of waste is causing major problems and environmental impacts. Thus, this work presents the study and the characterization of a composite material, aimed at the manufacture of an automotive bumper absorber. This material was manufactured with petroleum based polyurethane (PU) matrix resin and tire residue loading, from the retread process. Five formulations with different percentages of tire residue (0%, 30%, 45%, 70% and 100%) were obtained and characterized with respect to their mechanical and thermal properties, moisture absorption, density and degradation by exposure to the elements. Scanning Electron Microscopy (SEM) and Dispersive Energy Spectroscopy (EDS) tests were also performed on the material so that its microstructure could be observed (distribution of residues in the matrix, voids, imperfections and impurities) and to identify the chemical elements present , respectively. As a general result, the composites presented an increase in their density as the percentage of tire residue increased, as well as the thermal conductivity. As for the mechanical properties, the formulation with the highest tensile, flexural and compression strength was 45% and the one with the highest impact strength was 100%. Regarding the resistance to aging the formulation of 100% was the one that obtained better performance. A bumper absorber was manufactured with the 45% formulation, which presented a mass increase of 28.03%, demonstrating the feasibility of manufacturing this automotive component.

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