@MastersThesis{Silva:2014:EsFoIn,
author = "Silva, Patr{\'{\i}}cia Cristiane Santana da",
title = "Estudo da forma{\c{c}}{\~a}o de interface para
obten{\c{c}}{\~a}o de filmes de DLC altamente aderentes sobre
a{\c{c}}o",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2014",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2014-02-25",
keywords = "DLC, PECVD, ader{\^e}ncia, filmes finos, tela ativa, DLC, PECVD,
adherence, thin films, active screen.",
abstract = "O grande interesse no uso de filmes de carbono tipo diamante (DLC)
{\'e} justificado por suas not{\'a}veis propriedades
mec{\^a}nicas e tribol{\'o}gicas, como alta dureza, elevada
resist{\^e}ncia ao desgaste, in{\'e}rcia qu{\'{\i}}mica, e
baix{\'{\i}}ssimo coeficiente de atrito. Essa
combina{\c{c}}{\~a}o de propriedades {\'u}nicas confere ao
revestimento aplica{\c{c}}{\~o}es nas mais diversas {\'a}reas.
No entanto, o elevado n{\'{\i}}vel de tens{\~o}es compressivas,
que se originam durante o crescimento do filme, dificulta a
obten{\c{c}}{\~a}o de alta ader{\^e}ncia. Al{\'e}m disso, a
elevada dureza do filme aliada {\`a} diferen{\c{c}}a no
coeficiente de expans{\~a}o t{\'e}rmica em rela{\c{c}}{\~a}o
ao substrato faz com que o DLC n{\~a}o acompanhe facilmente a
deforma{\c{c}}{\~a}o do substrato, o que pode provocar a
delamina{\c{c}}{\~a}o e falha total do revestimento,
especialmente em a{\c{c}}os. Neste trabalho, filmes de DLC foram
depositados sobre o a{\c{c}}o r{\'a}pido AISI M2, utilizando a
t{\'e}cnica de deposi{\c{c}}{\~a}o qu{\'{\i}}mica na fase
vapor assistida por plasma (PECVD), visando o aumento de
ader{\^e}ncia atrav{\'e}s do estudo da deposi{\c{c}}{\~a}o de
interface de sil{\'{\i}}cio. Foi introduzida uma
modifica{\c{c}}{\~a}o na t{\'e}cnica convencional. A
ader{\^e}ncia foi avaliada em fun{\c{c}}{\~a}o dos
par{\^a}metros de deposi{\c{c}}{\~a}o, como tempo, energia de
bombardeio, press{\~a}o, e da deposi{\c{c}}{\~a}o em
multicamadas. Al{\'e}m disso, foi estudada a
densifica{\c{c}}{\~a}o do plasma com objetivo de aumentar a
ades{\~a}o por diferentes m{\'e}todos, entre os quais, a
inser{\c{c}}{\~a}o de g{\'a}s arg{\^o}nio na atmosfera de
deposi{\c{c}}{\~a}o, e a modifica{\c{c}}{\~a}o no arranjo
interno do sistema de deposi{\c{c}}{\~a}o. Baseando-se na
tecnologia de ASPN (\emph{Active Screen Plasma Nitriding}),
utilizada na nitreta{\c{c}}{\~a}o, foram desenvolvidas
diferentes configura{\c{c}}{\~o}es de tela ativa, promovendo
efeito de confinamento de el{\'e}trons. Testes tribol{\'o}gicos
foram realizados para se analisar a ader{\^e}ncia entre filme e
substrato, o coeficiente de atrito, e a resist{\^e}ncia ao
desgaste. A t{\'e}cnica de espectroscopia Raman foi utilizada
para verificar o arranjo estrutural dos {\'a}tomos de carbono e
obter par{\^a}metros importantes. Os filmes foram adicionalmente
caracterizados por microscopia eletr{\^o}nica de varredura (MEV),
perfilometria {\'o}ptica e de contato. Os resultados mostraram
que dentre todas as metodologias testadas, a deposi{\c{c}}{\~a}o
em tela ativa apresentou o melhor resultado em ganho de
ader{\^e}ncia, aliado {\`a} aplica{\c{c}}{\~a}o de alta
energia de bombardeio dos {\'{\i}}ons na deposi{\c{c}}{\~a}o
da interface de sil{\'{\i}}cio. ABSTRACT: The great interest in
the use of diamond-like carbon (DLC) films is justified by their
remarkable mechanical and tribological properties such as high
hardness, high wear resistance, chemical inertness, and a very low
friction coefficient. This combination of unique properties gives
the coating applications in several areas. However, the high
levels of compressive stresses, which arise during film growth,
turn it difficult to obtain high adhesion. Furthermore, the films
high hardness combined with the difference in thermal expansion
coefficient, compared to the substrate, causes the DLC film not to
easily follow the substrate deformation, which can lead to
delamination and total failure of the coating, especially on
steel. In this work, DLC films were deposited on high speed steel
AISI M2, using the plasma enhanced chemical vapor deposition
(PECVD) technique, in order to increase adhesion by studying the
deposition of silicon interface. The conventional technique was
modified. Adherence was evaluated according to the deposition
parameters such as time, bombardment energy and pressure, and to
the multilayer deposition. Furthermore, the plasma densification
was studied in order to increase adhesion by different methods,
including the insertion of argon gas in the deposition atmosphere,
and by modifying internal arrangement of the deposition system.
Based on the ASPN (Active Screen Plasma Nitriding) technology used
in nitriding, different configurations of active screen were
developed, promoting electron confinament effect. Tribological
tests were performed to analyze the adhesion between film and
substrate, the friction coefficient, and wear resistance. Raman
spectroscopy technique was used to verify the structural
arrangement of the carbon atoms and obtain important parameters.
Films were further characterized by scanning electron microscopy
(SEM), optical and contact profilometry. Results showed that among
all tested methods, deposition using active screen showed the best
results in adherence gain, combined with the application of
high-energy ion bombardment in the silicon interface deposition.",
committee = "Machado, Jo{\~a}o Paulo Barros (presidente) and Trava-Airoldi,
Vladimir Jesus (orientador) and Corat, Evaldo Jos{\'e} and
Martins, Gislene Valdete",
englishtitle = "Study of interlayer formation in order to obtain extremely
adherents DLC films on steel",
language = "pt",
pages = "98",
ibi = "8JMKD3MGP7W/3FMPLGL",
url = "http://urlib.net/ibi/8JMKD3MGP7W/3FMPLGL",
targetfile = "publicacao.pdf",
urlaccessdate = "04 maio 2024"
}