Tribological characteristics of polycrystalline diamond films produced by chemical vapor deposition

1992 ◽  
Vol 7 (7) ◽  
pp. 1769-1777 ◽  
Author(s):  
M. Kohzaki ◽  
K. Higuchi ◽  
S. Noda ◽  
K. Uchida
Keyword(s):  
Friction Coefficient ◽  
Diamond Film ◽  
Room Temperature ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Diamond Surface ◽  
Tribological Characteristics ◽  
Test Environment ◽  
Friction Coefficients ◽  
Aisi 52100

Effects of surface roughness and crystallinity of polycrystalline diamond films on their tribological characteristics, as well as the effects of test environment, have been investigated. Friction and wear characteristics of the diamond films deposited on sintered SiC disks have been examined with a ball-on-disk tester in the absence of any lubricant. The friction coefficients of polished diamond films against SiC and Si3N4 balls were below 0.10 at room temperature while those of as-deposited films were around 0.20. The specific wear of counterparts on the polished film was five orders of magnitude smaller than on the as-deposited film. The friction coefficient between the polished diamond film and a AISI 52100 steel ball was about 0.20. Transfer of a small amount of AISI 52100 material to the diamond film was observed along the wear track of the polished diamond surface. Diamond films of high quality were more resistant to wear than the ones of low quality. On the other hand, the friction coefficients were not affected by the crystallinity of the diamond films in the present study. Tribological characteristics of the diamond films deteriorated with increasing sliding speed and ambient temperature. At 600 °C in dry N2, the friction coefficient of diamond films against a SiC ball was about 0.8, which was about ten times higher than that at room temperature in air.

Experimental study on the effect of surface texture on tribological properties of nanodiamond films under water lubrication

2021 ◽  
pp. 135065012110334
Author(s):  
Ying Yan ◽  
Xuelin Lei ◽  
Yun He
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Tribological Properties ◽  
Surface Texture ◽  
Diamond Film ◽  
Diamond Films ◽  
Nanocrystalline Diamond ◽  
Water Contact ◽  
Texture Density ◽  
Short Run

The effect of nanoscale surface texture on the frictional and wear performances of nanocrystalline diamond films under water-lubricating conditions were comparatively investigated using a reciprocating ball-on-flat tribometer. Although the untreated nanocrystalline diamond film shows a stable frictional state with an average friction coefficient of 0.26, the subsequent textured films show a beneficial effect on rapidly reducing the friction coefficient, which decreased to a stable value of 0.1. Furthermore, compared with the nanocrystalline diamond coating, the textured films showed a large decreasing rate of the corresponding ball wear rate from 4.16 × 10−3 to 1.15 × 10−3 mm3/N/m. This is due to the fact that the hydrodynamic fluid film composed of water and debris can provide a good lubrication environment, so the entire friction process has reached the state of fluid lubrication. Meanwhile, the surface texture can greatly improve the hydrophilicity of the diamond films, and as the texture density increases, the water contact angle decreases from 94.75° of the nanocrystalline diamond film to 78.5° of the textured films. The proper textured diamond film (NCD90) exhibits superior tribological properties among all tested diamond films, such as short run-in period, low coefficient of friction, and wear rate.

Examination of the material properties and performance of thin-diamond film cutting tool inserts produced by arc-jet and hot filament chemical vapor deposition

1996 ◽  
Vol 11 (7) ◽  
pp. 1765-1775 ◽  
Author(s):  
James M. Olson ◽  
Michael J. Dawes
Keyword(s):  
Wear Resistance ◽  
Chemical Vapor Deposition ◽  
Diamond Film ◽  
Vapor Deposition ◽  
Cutting Tool ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
And Performance ◽  
Hot Filament

Thin diamond film coated WC-Co cutting tool inserts were produced using arc-jet and hot-filament chemical vapor deposition. The diamond films were characterized using SEM, XRD, and Raman spectroscopy to examine crystal structure, fracture mode, thickness, crystalline orientation, diamond quality, and residual stress. The performance of the tools was evaluated by comparing the wear resistance of the materials to brazed polycrystalline diamond-tipped cutting tool inserts (PCD) while machining A390 aluminum (18% silicon). Results from the experiments carried out in this study suggest that the wear resistance of the thin diamond films is primarily related to the grain boundary strength, crystal orientation, and the density of microdefects in the diamond film.

Tribological Characteristics on the Helical Gear in Cold Forging Mold

2011 ◽  
Vol 704-705 ◽  
pp. 277-283
Author(s):  
Won Sik Choi ◽  
Jae Hwan Son ◽  
Inh Lee ◽  
Eun Young Jin ◽  
Ju Ri Kwon ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Kinematic Viscosity ◽  
Hydrodynamic Lubrication ◽  
Test System ◽  
Helical Gear ◽  
Tribological Characteristics ◽  
Cold Forging ◽  
Sliding Velocity ◽  
Friction Coefficients ◽  
Lubrication Condition

The purpose of this study is to find out the tribological characteristics of the various lubricants in cold forging of helical gear, which is used in mobile auto-transmission. Five kinds of lubricant were used in this study, i.e. L1, L2, L3, L4 and L5. The pin-on-disk type of friction wear test system has been adopted here. The normal load of 20, 40, 60, 80 and 100N has been applied to the test specimen. The sliding velocities were 0.06, 0.10, 0.14, 0.18, 0.22, 0.26, 0.30 and 0.34m/s. Experimental results show that the friction coefficients of oils having higher kinematic viscosity such as L1, L2, L4 and L5 tend to increase gradually as the sliding velocity increases. The increasing rate of the friction coefficient is relatively high in lower sliding velocity range. However in case of L3 which has low kinematic viscosity the friction coefficient tends to decrease as the sliding velocity increases. The friction coefficients of Bondelube and Bondelite were 3 times higher than those of L1 and L5. The Stribeck curve indicates that L1, L2, L4 and L5 were in hydrodynamic lubrication condition and L3 was in boundary lubrication condition. SEM micrographs revealed that there were some scratch, adhesive wear, adhesion wear and scuffing on the worn surface.

Polycrystalline Diamond Film Resistors

1992 ◽  
Vol 242 ◽  
Author(s):  
L. M. Edwards ◽  
J. L. Davidson
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Plasma Cvd ◽  
Microwave Plasma Cvd ◽  
P Type ◽  
Polycrystalline Diamond Film ◽  
Effective Source

ABSTRACTThe technology to fabricate polycrystalline diamond film resistors has been initiated using modified thick film patterning techniques and in situ solid source doping.Doping of polycrystalline diamond films in microwave plasma CVD systems has been achieved historically through use of diborane gas, which may contaminate the deposition system causing all diamond films thereafter to be doped p-type. We have attempted noncontaminating in situ doping utilizing two solid source dopants, and have met with preliminary success.The more effective source (B2O3) produces a fairly even dopant concentration across the substrate, with sheet resistances ranging from 800 ohms per square to 4500 ohms per square. The other source (BN) showed significant doping in a narrow band surrounding the source, but the doping concentration decreased rapidly with distance from the source. Films grown afterwards with no doping were evaluated through resistance measurements; no evidence of doping contamination was observed.

Fabrication and Characteristics of TiO2 Nanotubes on Hemispherical Diamond Films Using ZnO Nanorods as Template

NANO ◽  
2015 ◽  
Vol 10 (06) ◽  
pp. 1550083 ◽  
Author(s):  
Qiliang Wang ◽  
Qi Yu ◽  
Junsong Liu ◽  
Taotao Ai ◽  
Hongdong Li
Keyword(s):  
Raman Spectroscopy ◽  
Zinc Oxide ◽  
Liquid Phase ◽  
Diamond Film ◽  
Tio2 Nanotubes ◽  
Chemical Etching ◽  
Room Temperature ◽  
Zno Nanorods ◽  
Diamond Films ◽  
Liquid Phase Deposition

Zinc oxide ( ZnO ) nanorods (NRs) have been synthesized as a template to fabricate TiO 2 nanotubes ( TiNTs ) on hemispherical diamond film by liquid-phase deposition (LPD) method. The process concerning the formation of TiNTs was analyzed. Based on the results of XRD and Raman spectroscopy, it is demonstrated that TiNTs was successfully obtained after removing ZnO NRs by chemical etching at room temperature. The TiNTs on hemispherical diamond film show higher performance photocatalysis, examined by the degradation of the reactive yellow 15 (RY15) solution. The corresponding mechanism is discussed.

Microstructure of polycrystalline diamond film

1990 ◽  
Vol 48 (4) ◽  
pp. 708-709
Author(s):  
M. G. Burke ◽  
R. E. Witkowski ◽  
R. T. Blackham
Keyword(s):  
Electron Microscopy ◽  
Diamond Film ◽  
Microwave Plasma ◽  
Plasma Deposition ◽  
Analytical Electron Microscopy ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Optical Systems ◽  
Power Sources

Diamond films have attracted considerable attention for use in a wide variety of industrial and commercial applications, particularly as coatings. Diamond coatings will enhance the performance of electro-optical systems, space-based photovoltaic power sources, packages for power electronic devices, and wear-limited processing equipment. These films are generally grown via plasma deposition or chemical vapor deposition techniques using a mixture. To characterize the as-grown diamond films, a variety of techniques including transmission electron microscopy are utilized. For this study, films were grown in a 1.5 kW ASTeX High Pressure Microwave Plasma Source equipped with an austenitic stainless steel, quartz lined reaction chamber. The plasma was a mixture of 0.5 or 2.0% CH4 in H2 at a reactor pressure of 30-50 mm Hg. During deposition, the substrate was heatea to ∼900-950°C. It has been reported that variations in the growth conditions will markedly affect the microstructure of the diamond film; several film morphologies have been observed. The quality of the substrate also exerts a strong effect on the nucleation of the diamond. In this on-going study, the influence of film thickness on the microstructure of polycrystalline diamond films has been characterized by analytical electron microscopy.

Tribo-Map of CVD Diamond Film Sliding against Silicon Nitride in Air

2013 ◽  
Vol 589-590 ◽  
pp. 405-410 ◽  
Author(s):  
Su Lin Chen ◽  
Bin Shen ◽  
Fang Hong Sun
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Diamond Film ◽  
Diamond Films ◽  
Ambient Air ◽  
Cvd Diamond ◽  
Sliding Velocity ◽  
Sliding Speed ◽  
Wear Rates ◽  
Cvd Diamond Film

The tribo-map of typical CVD diamond film exhibiting the interaction between the wear rate, friction coefficient and friction conditions would help optimize the working parameters of CVD diamond film coated tools and wear-resistance components. The tribological behaviors of CVD diamond films sliding against Si3N4 balls were studied by conducting a group of tests on the ball-on-plate type reciprocating friction tester under several sliding speeds and normal loads in the ambient air. The examined MCD films and NCD films were deposited on square flat WC-Co substrates. The worn surfaces on the diamond films were observed by SEM and the wear volumes of diamond films were measured by surface profilometer. The results indicated that the influences of the sliding speeds and normal loads on the friction coefficients for both MCD films and NCD films were obvious. When the load was 6 N, MCD film obtained the lowest friction coefficient of 0.11 at the sliding velocity of 0.2 m/s, while for NCD film the minimum value was 0.07 as the sliding speed was 0.13 m/s. The wear rate of the MCD film decreased as the load improved, while for the NCD film, the tendency was just the opposite. The influence of sliding speed on the wear rate of the MCD films was not distinct, while for the NCD films, the sliding velocity greatly affects their wear rate. The wear rates of most NCD films were around 0.2×10-7 mm3/Nm, while those of the MCD films fluctuated from 0.6×10-7~1.6×10-7 mm3/Nm. To elucidate the effect of operating environment on wear mechanism of diamond/ Si3N4 tribo-pair, the tribo-map was developed.

Air oxidation of undoped and B-doped polycrystalline diamond films at high temperature

1996 ◽  
Vol 11 (2) ◽  
pp. 296-304 ◽  
Author(s):  
Koichi Miyata ◽  
Koji Kobashi
Keyword(s):  
High Temperature ◽  
Etching Rate ◽  
Diamond Films ◽  
Polycrystalline Diamond ◽  
Temperature Treatment ◽  
Diamond Surface ◽  
High Temperature Treatment ◽  
Air Oxidation ◽  
B Doping ◽  
Electron Energy Loss

Air oxidation of undoped and B-doped polycrystalline diamond films was investigated at temperatures between 500 and 700 °C. Diamond (111) facets were etched for both undoped and B-doped films after 1 h at 700 °C. The etching rate of (111) facet due to oxidation was approximately 50% lower by B-doping of 1 × 1019 cm−3, presumably because of the decrease of sp2 bands and lattice defects that were identified by Raman and photoluminescence spectroscopy. X-ray photoelectron and electron energy loss spectroscopy revealed that by the high temperature treatment, the diamond surface was initially converted into graphite and successively etched by oxygen.

Electrical Properties of Diamond for Device Applications

1995 ◽  
Vol 416 ◽  
Author(s):  
B. A. Fox ◽  
M. L. Hartsell ◽  
D. M. Malta ◽  
H. A. Wynands ◽  
G. J. Tessmer ◽  
...  
Keyword(s):  
Hall Effect ◽  
Diamond Film ◽  
Room Temperature ◽  
Variable Temperature ◽  
Diamond Films ◽  
Hole Mobility ◽  
Cvd Diamond ◽  
Device Fabrication ◽  
Capacitance Voltage ◽  
Semiconducting Diamond

ABSTRACTThe semiconducting properties of diamond make it a material of interest for the fabrication of active electronic devices. Device performance depends on the properties of the host diamond film and the device structure. Improvements in the electronic properties of chemical vapor deposited (CVD) diamond films and in device design are required for development of commercial diamond devices. Hall-effect and capacitance-voltage measurements have been used to assess the electronic quality of diamond films and to evaluate potential device materials and structures. Homoepitaxial, highly oriented and polycrystalline CVD diamond films have been deposited and characterized by variable-temperature Hall-effect measurements. The highest room temperature hole mobility measured in a homoepitaxial film was 1590 cm2 /V•s where the compensation was ∼2 × 1015 cm-3. These properties are now beginning to approach those of the best type IIb natural diamonds. In a comparison of homoepitaxial, highly oriented diamond film, and polycrystalline diamond films, the room temperature hole mobility was 1470, 229 and 70 cm2/V•s, respectively. This data provides further evidence that the alignment of the grains improves the transport properties of diamond films. Capacitance-voltage measurements have been performed on single crystal type lib diamond with metal-insulating diamond-semiconducting diamond and metal-oxi de-semiconducting diamond structures. Using a conductance versus frequency technique, the density of interface states was estimated to be ∼1012 cm-2eV-1 for both structures. Although optimization of these structures must still be performed, the ability to measure the interface trap density offers the opportunity to provide direct feedback to the device fabrication process so that the structure may be optimized.

In-Situ Characterization of Thin Polycrystalline Diamond Film Quality by Thermal Wave and Raman Techniques

1989 ◽  
Vol 162 ◽  
Author(s):  
R. W. Pryor ◽  
P. K. Kuo ◽  
L. Wei ◽  
R. L. Thomas ◽  
P. L. Talley
Keyword(s):  
Thermal Conductivity ◽  
Laser Beam ◽  
Probe Beam ◽  
Diamond Film ◽  
Thermal Wave ◽  
Diamond Films ◽  
Film Surface ◽  
Polycrystalline Diamond ◽  
Probe Laser ◽  
Wave Technique

ABSTRACTIn this paper, the thermal wave technique and microfocus Raman spectroscopy are used to measure the relative quality of thin diamond films deposited on silicon. The thermal wave technique uses a modulated heating laser beam, normal to the diamond film surface, to initiate a thermal wave which propagates into the film, the substrate, and the overlying gas(ses). The accompanying modulated gas density is then interrogated by a second (probe) laser beam. The probe beam is deflected by the corresponding periodic changes in the gradient of the refractive index of the gas. The measured probe beam deflection versus offset position is fitted, using a theoretical solution of the three-dimensional thermal diffusion equation for the gas/film/substrate system. The physically important fitting parameter is the thermal diffusivity of the diamond film. Thermal conductivities derived from our diffusivity measurements using this method compare well to previous measurements on similarly prepared films by other methods. Our measured values for the thermal conductivity of the highest-quality polycrystalline diamond films are of the order of 12 W/cm-K. Our measured values of thermal conductivity for diamond films range between this value and the thermal conductivity of graphite. We have also made measurements on bulk diamond using the thermal wave technique, and we obtain a thermal conductivity of 21 W/cm-K, in excellent agreement with values found in the literature. A multi-scan, microfocus ratio of “graphitic” material to diamond material for a relative assessment of film quality.

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