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Tulio Matenciohttp://lattes.cnpq.br/0675398539252938Vanessa de Freitas Cunha LinsRoberto Braga FigueiredoRenata Braga Soareshttp://lattes.cnpq.br/9265589642628820Beatriz Araújo Batista2020-11-19T21:36:59Z2020-11-19T21:36:59Z2020-07-17http://hdl.handle.net/1843/34388Está bem estabelecido que o ferro (Fe) é um material promissor para uso em aplicações biomédicas. No entanto, ele exibe uma taxa de corrosão muito lenta quando presente em meios fisiológicos, o que pode torná-lo incompatível para aplicação como implantes degradáveis. Neste trabalho, o ferro puro processado por HPT (High-Pressure Torsion), que é uma técnica que consiste em aplicar no material uma alta pressão em conjunto com a torção, produzindo assim materiais altamente deformados plasticamente com grãos ultrafinos, foi submetido a diferentes temperaturas de recozimento. A influência do tamanho de grão do ferro nas propriedades químicas e mecânicas das amostras foi avaliada. Para isso foram realizados testes para analisar a resistência à corrosão em solução de Hank (imersão estática, polarização potenciodinâmica e espectroscopia de impedância eletroquímica) e as propriedades mecânicas (compressão e microdureza) do material em estudo, relacionando-as à microestrutura do ferro, que foi avaliada usando-se microscopia eletrônica de varredura acoplada com espectroscopia de energia dispersiva de raios-X e pela difração de raios-X. O material obteve granulometrias ultrafinas de cerca de 5 µm a 200 nm. Tensões de escoamento superiores a 1GPa foram obtidas em amostras de grão ultrafino, possibilitando a produção de implantes de suporte de carga com dimensões menores. Amostras com tamanhos de grão ultrafinos exibiram taxas de corrosão muito baixas (cerca de 0,016 mm.ano-1) e ao ficarem imersas por 28 dias na solução de Hank desenvolveram uma camada superficial homogênea de produtos de corrosão contendo a hidroxiapatita. O processamento por deformação plástica severa seguida de recozimento pode produzir ferro puro com propriedades mecânicas melhoradas e com biodegradabilidade mais lenta.It is well established that iron (Fe) is a promising material for use in biomedical applications. However, it exhibits a very slow corrosion rate when present in physiological media, which can make it incompatible for application as degradable implants. In this work, pure iron processed by HPT (High-Pressure Torsion), which is a technique that consists of applying high pressure to the material together with the torsion, thus producing highly plastically deformed materials with ultrafine grains, was subjected to different temperatures annealing process. The influence of the grain size of the iron on the chemical and mechanical properties of the samples was evaluated. For that, tests were carried out to analyze the corrosion resistance in Hank's solution (static immersion, potentiodynamic polarization, and electrochemical impedance spectroscopy) and the mechanical properties (compression and microhardness) of the material under study, relating them to the iron microstructure, which was evaluated using scanning electron microscopy coupled with X-ray dispersive energy spectroscopy and X-ray diffraction. The material obtained ultrafine particle sizes of about 5 µm at 200 nm. Flow tensions greater than 1GPa were obtained in samples of ultrafine grain, enabling the production of load-bearing implants with smaller dimensions. Samples with ultrafine grain sizes exhibited very low corrosion rates (about 0.016 mm.year-1) and when immersed for 28 days in Hank's solution they developed a homogeneous surface layer of corrosion products containing hydroxyapatite. Processing by severe plastic deformation followed by annealing can produce pure iron with improved mechanical properties and slower biodegradability.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorporUniversidade Federal de Minas GeraisPrograma de Pós-Graduação em Engenharia QuímicaUFMGBrasilENG - DEPARTAMENTO DE ENGENHARIA QUÍMICAhttp://creativecommons.org/licenses/by-nc-nd/3.0/pt/info:eu-repo/semantics/openAccessEngenharia químicaBiomateriaisFerroFerro puroHPTRecozimentoBiomaterialEstudo da resistência à corrosão e mecânica do ferro ARMCO na solução de Hank após processamento por torção sob alta pressão (High-Pressure Torsion)Study of corrosion and mechanical resistance of ARMCO iron in Hank's solution after high-pressure torsion processing (HPT)info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGORIGINALDissertação_Beatriz_Araujo_Batista.pdfDissertação_Beatriz_Araujo_Batista.pdfapplication/pdf2340856https://repositorio.ufmg.br/bitstream/1843/34388/1/Disserta%c3%a7%c3%a3o_Beatriz_Araujo_Batista.pdf6322024d173a81f263e4c1828d6ea275MD51CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8811https://repositorio.ufmg.br/bitstream/1843/34388/2/license_rdfcfd6801dba008cb6adbd9838b81582abMD52LICENSElicense.txtlicense.txttext/plain; charset=utf-82119https://repositorio.ufmg.br/bitstream/1843/34388/3/license.txt34badce4be7e31e3adb4575ae96af679MD531843/343882020-11-19 18:36:59.262oai:repositorio.ufmg.br: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Repositório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2020-11-19T21:36:59Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
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