812 Influence of DLC film structure on corrosion resistance

2013 ◽  
Vol 2013.21 (0) ◽  
pp. _812-1_-_812-3_
Author(s):  
Atsuyuki TAKARADA ◽  
Naoto OHTAKE ◽  
Hiroki AKASAKA
2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Nutthanun Moolsradoo ◽  
Shuichi Watanabe

Pure DLC, Si-DLC, and Si-N-DLC films deposited from C2H2, C2H2 : TMS and C2H2 : TMS : N2 mixtures were used to study the effects of the elemental contents (silicon, silicon-nitrogen) on deposition and corrosion resistance properties. The films were prepared on Si (100) wafers using the plasma-based ion implantation (PBII) technique. The film structure was analyzed using Raman spectroscopy. The composition at the top surface of the films was measured using energy dispersive X-ray spectroscopy (EDS). The hardness and elastic modulus of the films were measured using a nanoindentation hardness tester. The corrosion performance of the films was conducted using potentiodynamic polarization experiments in an aqueous 0.05 M NaCl solution. The results indicate that the hardness and corrosion resistance of the Si-DLC film increase as the silicon content increases. This is due to the increase of the sp3 cluster. The corrosion resistance of a pure DLC film increases when silicon and silicon-nitrogen are doped into the film. Si-DLC films with a silicon content of 40 at.% had a corrosion potential value of 0.61 V, while a Si-N-DLC film with a silicon and nitrogen content of 19.3 at.% and 1 at.% shows a corrosion potential value of 0.85 V, which is a considerable improvement in the corrosion resistance property.


2017 ◽  
Author(s):  
Nikolay P. Aban'shin ◽  
Garif G. Akchurin ◽  
Yuri A. Avetisyan ◽  
Alexander P. Loginov ◽  
Denis S. Mosiyash ◽  
...  

1999 ◽  
Vol 576 ◽  
Author(s):  
T. L. Metroke ◽  
R. L. Parkhill ◽  
E. T. Knobbe

ABSTRACT1H-13C and 1H- 29Si CP/MAS NMR spectroscopy has been used to characterize the structure of sol-gel derived hybrid materials prepared from 3-glycidoxypropyltrimethoxysilane (GLYMO) and tetraethylorthosilicate (TEOS) as a function of hydrolysis water ratio and organic content. 1H-13C CP/MAS NMR data indicate that the concentration of hydrolysis water (R value) has a fundamental effect on the nature of the acid-catalyzed hydrolysis and ring opening products. 1H-29Si CP/MAS NMR data suggest that for low R values, the ormosils are composed of a silica network with epoxide groups randomly dispersed throughout. At high R values, epoxide functionalities were found to coat the surfaces of dense silica particles. Salt spray analysis indicates that the corrosion resistance behavior of thin films derived from GLYMOTEOS ormosils decreases as the concentration of hydrolysis water increases and improves as the organic content in the film increases. These observations can be related to the underlying thin film structure.


RSC Advances ◽  
2016 ◽  
Vol 6 (18) ◽  
pp. 14756-14762 ◽  
Author(s):  
Hongqing Feng ◽  
Xiaolin Zhang ◽  
Guosong Wu ◽  
Weihong Jin ◽  
Qi Hao ◽  
...  

A corrosion protective DLC film is deposited on magnesium alloy AZ31, and exhibits strong anti-bacterial ability caused by the combined effects of the bacteria adhesion favorable surface and the local release of killing elements from the substrate.


2006 ◽  
Vol 956 ◽  
Author(s):  
Kazuya Kanasugi ◽  
Yasuharu Ohgoe ◽  
Katsuya Tsuchimoto ◽  
Keisuke Sato ◽  
Kenji K. Hirakuri ◽  
...  

ABSTRACTDiamond-like carbon (DLC) film was deposited uniformly on an irregular structure such as a polyurethane artificial heart blood pump using a special 3-dimensional type electrode. Process of applying the DLC film coating is accomplished by inserting a large number of small metallic balls (φ0.8 mm chromium balls). It is then possible to adjust the shape of the electrode in such a way that the DLC film coating can be applied to the irregular surface of the artificial heart. In investigating the availability of the electrode, under helium (He) plasma, the plasma states were measured using double probe analysis. Lateral profiles of the electron temperature were higher in the centre and decreased towards the edges of the electrode. On the other hand, the plasma density profiles were lower in the centre part than at the edges. The electrode kept ion sheath on the artificial heart blood pump's surface at self-bias voltage uniformly. The results were that the DLC film was deposited completely on the artificial heart blood pump at the film thickness of approximately 350 - 380 nm. Additionally the film structure was uniform.


Friction ◽  
2021 ◽  
Author(s):  
Changning Bai ◽  
Li Qiang ◽  
Bin Zhang ◽  
Kaixiong Gao ◽  
Junyan Zhang

AbstractDiamond-like carbon (DLC) films directly deposited on rubber substrate is undoubtedly one optimal option to improve the tribological properties due to its ultralow friction, high-hardness as well as good chemical compatibility with rubber. Investigating the relationship between film structure and tribological performance is vital for protecting rubber. In this study it was demonstrated that the etching effect induced by hydrogen incorporation played positive roles in reducing surface roughness of DLC films. In addition, the water contact angle (CA) of DLC-coated nitrile butadiene rubber (NBR) was sensitive to the surface energy and sp2 carbon clustering of DLC films. Most importantly, the optimum tribological performance was obtained at the 29 at% H-containing DLC film coated on NBR, which mainly depended on the following key factors: (1) the DLC film with appropriate roughness matched the counterpart surface; (2) the contact area and surface energy controlled interface adhesive force; (3) the microstructure of DLC films impacted load-bearing capacity; and (4) the generation of graphitic phase acted as a solid lubricant. This understanding may draw inspiration for the fabrication of DLC films on rubber to achieve low friction coefficient.


2019 ◽  
Vol 825 ◽  
pp. 99-105
Author(s):  
Yutaroh Kimura ◽  
Xia Zhu ◽  
Hiromichi Toyota ◽  
Ryoya Shiraishi ◽  
Yukiharu Iwamoto ◽  
...  

This study was performed to improve the adhesiveness of a diamond-like carbon (DLC, a-C:H) layer film with an a-SiC interlayer. In previous studies, an a-SiC/DLC layer film was formed and changes in the DLC film structure and hardness caused by the thickness of the a-SiC layer were examined. After the a-SiC interlayer thickness increased and the G-peak position shifted to a lower frequency, the peak began shifting to higher frequencies. The G-peak position reached a minimum frequency at a film thickness of approximately 0.3 μm. In contrast, as the thickness of the a-SiC interlayer increased, the FWHM of the G-peak position increased almost monotonically and the number of sp3 bonds also increased. As the interlayer thickness increased, the hydrogen content in the DLC film increased, and then began decreasing, with the interlayer film thickness exhibiting a local maximum at approximately 0.3 μm. As for the DLC film hardness, a correlation between the hydrogen content and half width of the G-peak position was observed. When the hydrogen content was ≤40 at%, a positive correlation with the FWHM (G) was observed, and when the hydrogen content was 40 at% or above, a negative correlation with FWHM (G) was found. The adhesiveness of the DLC film and substrate was improved by forming an a-SiC thin film as an interlayer. The effects of the a-SiC thin film on DLC film quality were determined.


2000 ◽  
Vol 628 ◽  
Author(s):  
Tammy L. Metrokeand ◽  
Edward T. Knobbe

ABSTRACTSpray-coated, R-Si (OR')3 / TMOS (R = epoxide), thin films are being investigated as room temperature curing corrosion resistant coatings for 2024-T3 aluminum alloy. Solid state 1H-13C CP/MAS NMR indicates that primary aliphatic amines and super acids are effective crosslinkers for epoxide groups in aqueous ormosil systems. Incorporation of a crosslinking agent into the coating was found to reduce the cure time of the deposited film from >7 days to approximately 30 min. Accelerated salt spray and filiform corrosion resistance tests were conducted to determine the effects of crosslinking on the corrosion resistance behavior of ormosil thin films. The choice of curing agent was found to influence film structure and corrosion resistance properties. Amine cured thin films were hard and highly adherent to the aluminum alloy substrates, exhibiting excellent bare and filiform corrosion resistance, in addition to good compatibility with organic polymer paint systems. In contrast, the adhesion and corrosion resistance of super acid cured thin films to aluminum alloy substrates was significantly less, producing films which readily delaminated from the substrate. These observations can be related to the film structure.


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