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Previous issue date: 2012-03-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Interstitial compounds of titanium have been mainly studied due to the large range of
properties acquired when C, N, O and H atoms are added. In this work, surfaces of TiCxNy
were produced by thermochemical treatments assisted by plasma with different proportions of
Ar + N2 + CH4 gas mixture. The Ar gas flow was fixed in 4 sccm, varying only N2 and CH4
gas flows. During the thermochemical treatment, the plasma was monitored by Optical
Emission Spectroscopy (OES) for the investigation of the influence of active species. After
treatments, C and N concentration profile, crystalline and amorphous phases were analyzed
by Nuclear Reaction (NRA). Besides tribomechanical properties of the Ti surface were
studied through the nanohardness measurements and friction coefficient determination. The
worn areas were evaluated by profilometry and Scanning Electronic Microscope (SEM) in
order to verify the wear mechanism present in each material. It has been seen which the
properties like nanohardness and friction coefficient have strong relation with luminous
intensity of species of the plasma, suggesting a using of this characteristic as a parameter of
process / Compostos intersticiais de tit?nio t?m sido extensivamente estudados devido ? larga
faixa de propriedades adquiridas quando ?tomos de C, N, O e H s?o adicionados. Neste
trabalho, superf?cies de TiCxNy foram produzidas por tratamento termoqu?mico auxiliado por
plasma de diferentes misturas de N2 + Ar + CH4. Foi fixado o fluxo de Ar em 4 sccm
variando-se os fluxos de N2 e CH4. Durante o tratamento termoqu?mico, o plasma foi
monitorado por EEO para investiga??o da influ?ncia das esp?cies ativas. Ap?s o tratamento,
as superf?cies das amostras foram analisadas quanto ao perfil de concentra??o de C e N, fases
cristalinas e fases amorfas. Tamb?m foram analisadas suas propriedades tribomec?nicas
atrav?s da medida de nanodureza e da determina??o do coeficiente de atrito. As ?reas
desgastadas foram avaliadas por perfilometria e microscopia eletr?nica de varredura (MEV)
com o intuito de verificar os mecanismos de desgastes presentes em cada material. Verificouse
que propriedades como dureza e coeficiente de atrito variavam com a intensidade das
esp?cies, sugerindo o uso da mesma como par?metro de processos a plasma
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12752 |
| Date | 02 March 2012 |
| Creators | Rocha, Ricardo Cesar da Silva |
| Contributors | CPF:09621199468, http://lattes.cnpq.br/7441669258580942, Melo, Anderson Clayton Alves de, CPF:87652919487, http://lattes.cnpq.br/5242440649066569, Santos, Lucia Vieira, CPF:10293228809, http://lattes.cnpq.br/4359261479122193, Alves J?nior, Clodomiro |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncia e Engenharia de Materiais, UFRN, BR, Processamento de Materiais a partir do P?; Pol?meros e Comp?sitos; Processamento de Materiais a part |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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