Made available in DSpace on 2014-12-17T14:58:21Z (GMT). No. of bitstreams: 1
EdsonJCS_DISSERT.pdf: 1649413 bytes, checksum: 32339cc7487693336b6710eaa3e1c93c (MD5)
Previous issue date: 2013-07-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Many applications require that the plasma discharge is produced apart from the surface to be processed, thus preventing damage caused by bombardment and/or plasma radiation. In the post-discharge regime in various applications thermally sensitive materials can be used. In this work, active species produced by discharge and post-discharge hollow cathode were diagnosed by optical emission spectroscopy and mass spectrometry. The discharge was produced with the gases Ar and Ar - N2 gas flow ranging from 1 to 6 cm3/min and electric current between 150 to 600 mA. It was estimated that the ion density inside the hollow cathode, with 2 mm diameter ranged between 7.71 and 14.1 x 1015 cm-3. It was observed that the gas flow and the electric current changes the emission intensity of Ar and N2 species. The major ionic species detected by quadrupole mass spectrometry were Ar+ and N2+. The ratio of optical emission intensities of N2(1 +)/Ar(811 nm) was related to the partial pressure of N2 after the hollow cathode discharge at low pressure / Muitas aplica??es de plasma exigem que a descarga seja produzida distante da superf?cie a ser processada, evitando assim danos causados pelo bombardeamento e/ou radia??o do plasma. Nesse regime de p?s-descarga v?rias aplica??es em materiais termicamente sens?veis podem ser utilizadas. Neste trabalho esp?cies ativas produzidas por descarga e p?s-descarga de catodo oco foram diagnosticadas por espectroscopia de emiss?o ?ptica e espectrometria de massa. A descarga foi produzida com os gases Ar e mistura Ar - N2 com fluxo de g?s variando de 1 a 6 cm3/min e corrente el?trica entre 150 a 600 mA. Estimou-se que a densidade de ?ons no interior do c?todo oco, com 2 mm de di?metro, variou entre 7,71 e 14,1 x 1015 cm-3. Observou-se que o fluxo de g?s e a corrente el?trica alteram a intensidade de emiss?o das esp?cies de Ar e N2. As principais esp?cies i?nicas detectadas por espectrometria de massa quadrupolar foram de Ar+ e N2+. A raz?o das intensidades de emiss?o ?tica de N2 (1 +)/Ar(811 nm) foi relacionada com a press?o parcial de N2 na p?s-descarga de c?todo oco em baixa press?o
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15707 |
| Date | 05 July 2013 |
| Creators | Santos, Edson Jos? da Costa |
| Contributors | CPF:46658564434, http://lattes.cnpq.br/5387010100082241, Alves J?nior, Clodomiro, CPF:09621199468, http://lattes.cnpq.br/7441669258580942, Costa, Th?rcio Henrique de Carvalho, CPF:03396191471, http://lattes.cnpq.br/3647710047561421, Almeida, Edalmy Oliveira de, CPF:99177781449, http://lattes.cnpq.br/1480791721671288, Barbosa, J?lio C?sar Pereira, CPF:03437433458, http://lattes.cnpq.br/0437190557200470, Guerra Neto, Cust?dio Leopoldino Brito |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Mec?nica, UFRN, BR, Tecnologia de Materiais; Projetos Mec?nicos; Termoci?ncias |
| 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 |
Page generated in 0.0023 seconds