Tribological Properties of Si-DLC Coatings Synthesized with Nitrogen, Argon Plus Nitrogen, and Argon Ion Beams

1997 ◽  
Vol 504 ◽  
Author(s):  
C. G. Fountzoulas ◽  
J. D. Demaree ◽  
L. C. Sengupta ◽  
J. K. Hirvonen ◽  
D. Dimitrov

ABSTRACTHard, adherent, and low-friction silicon-containing diamond-like carbon coatings (Si-DLC) have been synthesized at room temperature by 40 keV (N+ plus N2+), 50%Ar+/50% (N+ plus N2+), and Ar+ ion beam assisted deposition (IBAD) of a tetraphenyl-tetramethyl-trisiloxane oil on silicon and sapphire substrates. X-ray diffraction analysis indicated that all coatings were amorphous. The average coating wear rate and the average unlubricated steel ball-on-disk friction coefficient, μ, decreased with increasing fraction of nitrogen in the ion beam, along with an increase in the average coating growth rate. The Knoop microhardness and nanohardness values of the coatings synthesized by the mixed argon and nitrogen ion beam were higher than the values for the coatings synthesized with 100% nitrogen or 100%argon ion beams. These friction/wear improvements are tentatively attributed to both increased hardening due to greater penetration and ionization induced hardening by the lighter (N) ions and to the presence of Si02 on the surface of N-bombarded samples.

1996 ◽  
Vol 438 ◽  
Author(s):  
C. G. Fountzoulas ◽  
J. D. Demaree ◽  
L. C. Sengupta ◽  
J. K. Hirvonen

AbstractAmorphous, 700 nm thick, diamond-like carbon coatings containing silicon (Si-DLC), farmed by Ar+ ion beam assisted deposition (IBAD) on silicon substrates, were annealed in air at temperatures ranging from room temperature to 600°C for 30 minutes. RBS analysis showed that the composition of the films remained the same up to 200°C, but at higher temperatures the Si-DLC coatings began to oxidize at the outer surface of the coating, forming a surface layer of SiO2. After in-air annealing at 600°C the coating had been completely converted to SiO2, with no trace of carbon seen by RBS. FTIR spectra of the unannealed coatings showed a very broad mode typical of Si-DLC bonding as well as some absorption features associated with Si and SiO2. Above 200°C the transmission mode shifted to higher frequencies which may be caused by the growth of SiO2 and the decrease of the Si-DLC film thickness. The room temperature ball-on-disk friction coefficient of the coating against a 1/2′′ diameter 440 C steel ball at 1 N load ranged from 0.2 for the original coating up to 0.5 after a 100° anneal and returned to 0.2 after annealing at 200–400°C and fell to 0.12 after a 500°C exposure. The average Knoop microhardness (uncorrected for substrate effects) was 10 GPa (1,000 KHN) for coatings annealed at temperatures as high as 400°C. All coatings up to 500 °C passed the qualitative “Scotch Tape” test.


1988 ◽  
Vol 128 ◽  
Author(s):  
Zhou Jiankun ◽  
Liu Xianghuai ◽  
Chen Youshan ◽  
Zheng Zhihong ◽  
Huang Wei ◽  
...  

ABSTRACTTitanium nitride films have been synthesized at room temperature by alternate deposition of titanium and bombardment by nitrogen ions with an energy of 40KeV. The component depth profiles and the structure of titanium nitride films were investigated by means of RBS, AES, TEM, XPS and X-ray diffraction. The results showed that titanium nitride films formed by ion beam enhanced deposition (IBED) had columnar structure and were mainly composed of TiN crystallites with random orientation. The oxygen contamination in titanium nitride films prepared by IBED was less than that of the deposited film without nitrogen ion bombardment. It was confirmed that a significant intermixed layer exists at the interface. The thickness of this layer was about 40 nm for the film prepared on iron plate. The mechanical properties of the film have been investigated. The films formed by IBED exhibited high hardness, improved wear resistance and low friction.


2015 ◽  
Vol 1084 ◽  
pp. 11-15
Author(s):  
Sergey P. Umnov ◽  
Oleg Kh. Asainov ◽  
Svetlana N. Popova ◽  
Aleksey N. Lemachko

High-reflectance aluminum films are widely used in applied optics. As part of this work, we deposited aluminum films on glass substrates by magnetron sputtering using argon ion beam assistance. The reflectivity of the films obtained was measured on the SF-256 spectrophotometer. The microstructure and topology of the films were examined with a transmission electron microscope (TEM), X-ray diffraction (XRD) and atomic force microscope (AFM). The studies have shown that the aluminum films deposited with ion assistance have higher reflectance in the UV range than the films formed by magnetron sputtering alone. The results of TEM and AFM measurements show that the geometric factor (crystallite size, surface roughness) is not the reason for the increase of reflectivity. X-ray diffraction analyses have shown a significant increase in microstress in the aluminum films deposited with ion assistance, which is caused by an increase in the defect density of the vacancy-type crystal structure. The results have shown that the increase in the density of crystal defects leads to an increase in reflectance in the UV range.


1987 ◽  
Vol 110 ◽  
Author(s):  
B. L. Barthell ◽  
T. A. Archuleta ◽  
Ram Kossowsky

AbstractCalcium hydroxyapatite has been sputtered on glass and Ti-6Al-4V substrates using a 1.5-kV argon ion beam. The films have been examined by x-ray diffraction analysis, energy dispersive spectroscopy, scanning electron microscopy, and adhesion testing. Results of this experimentation are presented.


2015 ◽  
Vol 32 ◽  
pp. 60-65
Author(s):  
Oleg Ashkhotov ◽  
Irina Ashkhotova

Auger electron spectroscopy (AES) and electron energy loss spectroscopy (EELS) studied the interaction of argon ions with a natural oxide layer of polycrystalline aluminum. It was found that the bombardment of argon ions with an energy lower sputtering threshold Al2O3leads to accumulation of ions bombarding the interstitial voids in the surface, thereby forming a solid solution of atoms of the target, the argon ions and nitrogen ion beam, the captured residual gas from the chamber of the spectrometer.


1988 ◽  
Vol 100 ◽  
Author(s):  
E. J. Williams ◽  
E. G. Bithell ◽  
C. B. Boothroyd ◽  
W. M. Stobbs ◽  
R. J. Young ◽  
...  

ABSTRACTThe promotion of silicide reactions at the interface between silicon and a metal overlayer is described, the reactions being initiated by scanned ion beams. The relative effects of low and high energy Si+ and Si2+ beams are discussed and the results of subsequent annealing are compared with those seen when using low energy (5keV) argon ion beams. The implications for the writing of metallisation lines are also noted.


1992 ◽  
Vol 7 (2) ◽  
pp. 374-378 ◽  
Author(s):  
J-G. Choi ◽  
D. Choi ◽  
L.T. Thompson

A series of molybdenum nitride films were synthesized by implanting energetic nitrogen ions into molybdenum thin films. The resulting films were characterized using x-ray diffraction to determine the effects of nitrogen ion dose (4 × 1016−4 × 1017 N+/cm2), accelerating voltage (50–200 kV), and target temperature (∼298–773 K) on their structural properties. The order of structural transformation with increased incorporation of nitrogen ions into the Mo film can be summarized as follows: Mo → γ−Mo2N → δ−MoN. Nitrogen incorporation was increased by either increasing the dose or decreasing the ion energy. At elevated target temperatures the metastable B1–MoN phase was also produced. In most cases the Mo nitride crystallites formed with the planes of highest atomic density parallel to the substrate surface. At high ion energies preferential orientation developed so that the more open crystallographic directions aligned with the ion beam direction. We tentatively attributed this behavior to ion channeling effects.


Author(s):  
J. M. Martin ◽  
M. I. De Barros Bouchet ◽  
T. Le Mogne ◽  
M. Kano

Fuel economy and reduction of harmless elements in lubricant are becoming crucial in the automotive industry. An approach to respond these requirements in engine components is the potential use of low friction coatings exposed to specific boundary lubrication conditions. Superlubricity is a new research field in tribology, dealing with very low friction values, typically below 0.01, and this even in dry or vacuum conditions. It is to be noticed that any friction coefficient below 0.001 is hardly measurable with the equipment at hand. Superlow friction was already experimentally observed only in ultrahigh vacuum and inert gas environment, with pure molybdenite (MoS2) coatings [1] and in presence of some hydrogenated DLC coatings [2]. Under boundary lubrication, we show here that the coupling of hydrogen-free carbon coatings and selected organic lubricant additives permits to reach friction values approaching superlubricity and also a wearless behavior.


1997 ◽  
Vol 504 ◽  
Author(s):  
S. R. Kim ◽  
J. S. Song ◽  
Y. J. Choi ◽  
J. H. Kim

ABSTRACTPolycarbonate is one of the most widely used engineering plastics because of its transparency and high impact strength. The poor wear and scratch properties of polycarbonate have limited its application in many fields. In order to improve the wear and scratch properties of polycarbonate we have deposited diamond like carbon (DLC) coatings. The diamond like carbon coatings were made using a high frequency ion beam gun by introducing H2 and CH4 gases. The coatings were characterized with scanning electron microscope, Raman spectroscopy, ellipsometer, and microscratch tester. Polymer hard coating was applied onto the polycarbonate substrate before depositing a diamond like carbon coating to see the effect of interlayer on the system's failure mechanism.


Sign in / Sign up

Export Citation Format

Share Document