Adhesion Improvement of CVD Diamond Coatings on WC-Co Substrates for Machining Applications

2004 ◽  
Vol 843 ◽  
Author(s):  
Zhenqing Xu ◽  
Ashok Kumar ◽  
Leonid Lev ◽  
Michael Lukitsch ◽  
Arun Sikder
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Hydrogen Plasma ◽  
Cutting Tools ◽  
Indentation Test ◽  
Chemical Vapor ◽  
Diamond Powder ◽  
Nucleation Density ◽  
Diamond Coatings ◽  
Diamond Powders

ABSTRACTIn order to improve the performance of WC-Co cutting tools, high quality microcrystalline diamond coatings were produced using microwave plasma enhanced chemical vapor deposition (MPECVD) method. The adhesion of the diamond film deposited on the substrate has been considered to play an important role in the performance of the cutting tools in machining applications. A thin layer of Cr was coated on the WC-Co substrate before the diamond deposition; 75 μm diamond powders were sandblasted on the surface at 40 Psi to increase the nucleation density. Diamond film has been successfully deposited on the substrate at temperature around 750°C with 1.5 % CH4 in Hydrogen plasma. Scanning electron microscopy (SEM) has been used to study the surface morphology and Raman spectroscopy has been performed to characterize the quality of the diamond films and measure the residual stress. The adhesion of the diamond film has been evaluated by Rockwell indentation test. The results indicated that film grown on the Cr interlayer with diamond powder sandblasting has much better adhesion strength.

Deposition of Adherent Diamond Coatings on WC-Co Substrates

2005 ◽  
Vol 890 ◽  
Author(s):  
Zhenqing Xu ◽  
Leonid Lev ◽  
Michael Lukitsch ◽  
Ashok Kumar
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Hydrogen Plasma ◽  
Chemical Vapor ◽  
Diamond Powder ◽  
Film Structure ◽  
Nucleation Density ◽  
Diamond Coatings ◽  
X Ray Diffraction ◽  
Indentation Tests

ABSTRACTHigh quality well-adhered microcrystalline diamond coatings have been produced by the microwave plasma enhanced chemical vapor deposition (MPECVD) technique on cemented carbide substrates. A multi-interlayer system Cr/CrN/Cr was deposited on the WC-Co substrate before diamond deposition to work as a diffusion barrier. The coated substrate was peened with friable diamond powder to roughen the surface resulting in high nucleation density. Adherent diamond film has been successfully deposited on the substrate at temperature around 700°C with 1.0 % CH4 in Hydrogen plasma. The surface morphology and film structure has been studied by Scanning Electron Microscopy (SEM) and X-Ray diffraction technique. The adhesion of the diamond film has been evaluated by Rockwell indentation tests.

Nanocrystalline Diamond Film Produced by Argon Addition in the CH4-H2 Microwave CVD Plasmas

2007 ◽  
Vol 26-28 ◽  
pp. 615-618
Author(s):  
Syed Jawid Askari ◽  
Fan Xiu Lu
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Pure Titanium ◽  
Chemical Vapor ◽  
Nanocrystalline Diamond ◽  
Complex Nature ◽  
Nucleation Density ◽  
Diamond Coatings ◽  
Plasma Chemical Vapor Deposition ◽  
Thermal Expansion Coefficients

Diamond coatings on pure titanium substrates are of interest for tribological and biomedical implants. However, due to the different thermal expansion coefficients of the two materials, the complex nature of the interlayer formed during diamond deposition, and the difficulty in achieving very high nucleation density, it is hard to deposit adherent thin diamond layers on titanium. The aim of the present research was to successfully produce smooth and well adherent nanocrystalline diamond (NCD) film on a pure Ti substrate using the microwave plasma chemical vapor deposition (MWPCVD) method. The influence of Argon addition to CH4/H2 plasma on the crystallinity, morphology and growth of the diamond film deposited by MWPCVD was investigated using field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), Xray diffraction (XRD) and Raman spectroscopy.

Diamond nucleation on unscratched silicon substrates coated with various non-diamond carbon films by microwave plasma-enhanced chemical vapor deposition

1995 ◽  
Vol 10 (1) ◽  
pp. 165-174 ◽  
Author(s):  
Z. Feng ◽  
M.A. Brewer ◽  
K. Komvopoulos ◽  
I.G. Brown ◽  
D.B. Bogy
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Microwave Plasma ◽  
Hydrogen Plasma ◽  
Chemical Vapor ◽  
Carbon Films ◽  
Nucleation Density ◽  
Silicon Substrates ◽  
Hard Carbon ◽  
Diamond Nucleation

The efficacy of various non-diamond carbon films as precursors for diamond nucleation on unscratched silicon substrates was investigated with a conventional microwave plasma-enhanced chemical vapor deposition system. Silicon substrates were partially coated with various carbonaceous substances such as clusters consisting of a mixture of C60 and C70, evaporated films of carbon and pure C70, and hard carbon produced by a vacuum are deposition technique. For comparison, diamond nucleation on silicon substrates coated with submicrometer-sized diamond particles and uncoated smooth silicon surfaces was also examined under similar conditions. Except for evaporated carbon films, significantly higher diamond nucleation densities were obtained by subjecting the carbon-coated substrates to a low-temperature high-methane concentration hydrogen plasma treatment prior to diamond nucleation. The highest nucleation density (∼3 × 108 cm−2) was obtained with hard carbon films. Scanning electron microscopy and Raman spectroscopy demonstrated that the diamond nucleation density increased with the film thickness and etching resistance. The higher diamond nucleation density obtained with the vacuum are-deposited carbon films may be attributed to the inherent high etching resistance, presumably resulting from the high content of sp3 atomic bonds. Microscopy observations suggested that diamond nucleation in the presence of non-diamond carbon deposits resulted from carbon layers generated under the pretreatment conditions.

Deposition of a Well-Adherent Nano-Crystalline Diamond Coating on Titanium Using CH4-H2 Gas Mixture

2007 ◽  
Vol 561-565 ◽  
pp. 1145-1148
Author(s):  
Syed Jawid Askari ◽  
Fan Xiu Lu
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Pure Titanium ◽  
Titanium Substrate ◽  
Chemical Vapor ◽  
Complex Nature ◽  
Nucleation Density ◽  
Thermal Expansion Coefficients ◽  
Nano Crystalline ◽  
Average Grain Size

The deposition of a well adherent diamond film on titanium and its alloys is always complicated due to the different thermal expansion coefficients of the two materials, the complex nature of the interlayer formed during diamond deposition, and the difficulty in achieving very high nucleation density. In this work well-adherent and smooth nano-crystalline diamond film was successfully deposited on pure titanium substrate by microwave plasma assisted chemical vapor deposition (MWPCVD) method in CH4/H2 environment. It is found that the average grain size was less than 20 nm with a surface roughness value as low as 28nm. Of particular interest in this study was the exceptional adhesion of approximately 2μm-thick diamond film to the metal substrate as observed by indentation testing up to 150 kg load. Experimental results on growth mechanism and obtaining good adhesion are discussed.

Adhesion of Diamond Film to Co- Deficient Cemented Tungsten Carbide Substrate

2007 ◽  
Vol 336-338 ◽  
pp. 1728-1730
Author(s):  
Hong Lin Li ◽  
Li Gou ◽  
Jun Guo Ran
Keyword(s):  
Diamond Film ◽  
Microwave Plasma ◽  
Indentation Test ◽  
Chemical Vapor ◽  
Scratch Test ◽  
Good Adhesion ◽  
Plasma Chemical ◽  
Plasma Chemical Vapor Deposition ◽  
Strong Adhesion ◽  
Continuous Surface

Diamond film was synthesized on Co-deficient (Co content is about 0.5%) WC-Co substrate using microwave plasma chemical vapor deposition (MPCVD) equipment without special pretreatment. SEM, XRD, Rockwell-indentation test and scratch test were used to analyze the structure and morphology of the diamond film and its adhesion to the substrate. Co content was also measured by EDAX. The results show that the film synthesized is of ideal diamond structure with perfect and uniform grains, dense and continuous surface and strong adhesion. Co content on the surface of the substrate is about 0.8% after 20h deposition, which is considered as one of the main causes to get good adhesion.

Nano-Crystalline Diamond Films Deposited on Copper Substrate by MPCVD Method

2011 ◽  
Vol 117-119 ◽  
pp. 1310-1314
Author(s):  
Xing Rui Li ◽  
Xin Wei Shi ◽  
Ning Yao ◽  
Xin Chang Wang
Keyword(s):  
Diamond Film ◽  
Deposition Time ◽  
Microwave Plasma ◽  
Copper Substrate ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Annealing Process ◽  
Adhesive Properties ◽  
Plasma Chemical Vapor Deposition ◽  
Nano Crystalline

Nano-crystalline diamond (NCD) films with good adhesion were deposited on flexible copper substrate with Ni interlayer by Microwave Plasma Chemical Vapor Deposition (MPCVD). In this paper, two-stage method was used to improve the adhesion between the copper substrates and the diamond films. The effect of deposition time of the first stage on the morphology, crystal structure, non-diamond phase and adhesive properties of diamond films was investigated. The performance and structure of the diamond films were studied by Scanning Electron Microscope (SEM), Raman Spectroscopy (Raman) and X-Ray Diffraction (XRD). The results showed that the films were nano-crystalline diamond films positively. Impress method was used to examine the adhesion between diamond film and the substrate. When deposition time is 1.5h, the adhesion between diamond film and the copper substrate is better than the others. When it was 2.5h or longer, because the graphite layers existed as intermediate, the adherence between the diamond films and copper substrates was very poor. Therefore, the diamond films were easily peeled off from the substrates. Otherwise, the second stage called annealing process after the deposition played an important role to the adhesion. The films would be easily peeled off by curling without the annealing process.

Achieving High Nucleation Density of Diamond Film Under Low Pressures in Hot-Filament Chemical Vapor Deposition

1994 ◽  
Vol 363 ◽  
Author(s):  
Yan Chen ◽  
Jun Mei ◽  
Qijin Chen ◽  
Zhangda Lin
Keyword(s):  
Chemical Vapor Deposition ◽  
Diamond Film ◽  
Vapor Deposition ◽  
Crystalline Silicon ◽  
Chemical Vapor ◽  
Nucleation Density ◽  
Heteroepitaxial Growth ◽  
Hot Filament ◽  
Low Pressures ◽  
Gaseous Source

AbstractDiamond have been deposited rapidly under low pressures (<0.1 Torr) via hot filament chemical vapor deposition (HFCVD) on either scratched or mirror-smooth single crystalline silicon and titanium with nucleation densities of 109–1011/cm2. The nucleation density increases with the pressure decreases. Hydrogen and methane were used as the gaseous source. Raman spectroscopy and scanning electron microscopy(SEM) were used to analyze the obtained films. This result breaks through the limit that diamond film can only be synthesized above 10 Torr, showing a promising prospect that, as is essential for heteroepitaxial growth of monocrystalline diamond films, diamond film can be easily nucleated on unscratched substrate via Hot Filament CVD.

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