Surface morphology and bond characterization of nanocrystalline diamonds grown on tungsten carbide via hot filament chemical vapor deposition

Hamzah, Esah; Yong, Tze Mi; Yajid, Muhamad Azizi Mat

doi:10.1016/j.jcrysgro.2013.02.009

Cited by 8 publications

(4 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 6 (b) represents nanodiamonds with high crystallinity and different grain orientations, where the grain orientations are labeled by Crystalmaker with an incident beam along (001) shown in Figure 6c–k . The set of images clearly demonstrate the crystalline structure of the laser processed nanodiamond, and is in a good agreement with prior reports 18 38 41 42 . Based on the FFT patterns, it can be concluded the nanodiamond particles have high crystal quality.…”

Section: Resultssupporting

confidence: 91%

Direct Laser Writing of Nanodiamond Films from Graphite under Ambient Conditions

Nian

Wang

Yang

et al. 2014

Sci Rep

View full text Add to dashboard Cite

Synthesis of diamond, a multi-functional material, has been a challenge due to very high activation energy for transforming graphite to diamond, and therefore, has been hindering it from being potentially exploited for novel applications. In this study, we explore a new approach, namely confined pulse laser deposition (CPLD), in which nanosecond laser ablation of graphite within a confinement layer simultaneously activates plasma and effectively confine it to create a favorable condition for nanodiamond formation from graphite. It is noteworthy that due to the local high dense confined plasma created by transparent confinement layer, nanodiamond has been formed at laser intensity as low as 3.7 GW/cm2, which corresponds to pressure of 4.4 GPa, much lower than the pressure needed to transform graphite to diamond traditionally. By manipulating the laser conditions, semi-transparent carbon films with good conductivity (several kΩ/Sq) were also obtained by this method. This technique provides a new channel, from confined plasma to solid, to deposit materials that normally need high temperature and high pressure. This technique has several important advantages to allow scalable processing, such as high speed, direct writing without catalyst, selective and flexible processing, low cost without expensive pico/femtosecond laser systems, high temperature/vacuum chambers.

show abstract

Section: Resultssupporting

confidence: 91%

Direct Laser Writing of Nanodiamond Films from Graphite under Ambient Conditions

Nian

Wang

Yang

et al. 2014

Sci Rep

View full text Add to dashboard Cite

show abstract

“…According to Hamzah [ 24 ], damage to NCD coating either occurs (1) along the boundary of the ballas aggregate or (2) intergranularly at the nano-diamond boundary of the ballas aggregate. Therefore, delamination abrasion that includes several ballas occurs at the interface between the coating and substrate as the damage progresses according to the former case.…”

Section: Resultsmentioning

confidence: 99%

Effect of Coating Thickness on Abrasion and Cutting Performance of NCD-Coated Ball Endmills on Graphite Machining

Lee

Park

et al. 2023

Micromachines

View full text Add to dashboard Cite

Nano-crystalline diamond (NCD) coating to improve the performance of cutting tools, as the coating thickness varies, the cutting performance and lifespan of the tool varies because the radius of its cutting edge and coating surface roughness are altered. Therefore, an in-depth analysis on the impact of the variations in coating thickness on the cutting tool abrasion and quality of machined surface is necessary. In this study, two NCD ball endmills were coated with 8 and 12 μm thicknesses, and the tool abrasion and roughness of the machined plane were observed after milling. Furthermore, the morphology of the coated surface and abrased cutting edge were observed using a 3D confocal microscope. Consequently, we observed that individual nodules were formed on the continuous aggregates as the coating thickness increased, which increased the coated surface roughness. The two damage modes of the aggregation determined the dominant abrasion that occurred on the cutting edges of both types of coating thicknesses. Delamination and crater wear caused a sharp increase in the roughness of the machined surface. In summary, the increase in coating thickness delayed the delamination of the coating but increased the roughness of the cutting edge, which reduced the machined surface roughness.

show abstract

“…The synthesis of NCD films is typically performed using hot filament (HF CVD) [14,15] or microwave plasma assisted chemical vapor deposition (MPACVD) [10]. The HFCVD is commercially more interesting as it is inexpensive and allows the deposition of diamond on large surfaces and complex geometry substrates.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of High Quality Transparent Nanocrystalline Diamond Films on Glass Substrates Using a Distributed Antenna Array Microwave System

et al. 2022

View full text Add to dashboard Cite

Diamond is a material of choice for the fabrication of optical windows and for protective and anti-reflecting coatings for optical materials. For these kinds of applications, the diamond coating must have a high purity and a low surface roughness to guarantee a high transparency. It should also be synthesized at low surface temperature to allow the deposition on low melting-point substrates such as glasses. In this work, the ability of a Distributed Antenna Array (DAA) microwave system operating at low temperature and low pressure in H2/CH4/CO2 gas mixture to synthesize nanocrystalline diamond (NCD) films on borosilicate and soda-lime glass substrates is investigated aiming at optical applications. The influence of the substrate temperature and deposition time on the film microstructure and optical properties is examined. The best film properties are obtained for a substrate temperature below 300 °C. In these conditions, the growth rate is around 50 nm·h−1 and the films are homogeneous and formed of spherical aggregates composed of nanocrystalline diamond grains of 12 nm in size. The resulting surface roughness is then very low, typically below 10 nm, and the diamond fraction is higher than 80%. This leads to a high transmittance of the NCD/glass systems, above 75%, and to a low absorption coefficient of the NCD film below 103 cm−1 in the visible range. The resulting optical band gap is estimated at 3.55 eV. The wettability of the surface evolves from a hydrophilic regime on the bare glass substrates to a more hydrophobic regime after NCD deposition, as assessed by the increase of the measured contact angle from less than 55° to 76° after the deposition of 100 nm thick NCD film. This study emphasizes that such transparent diamond films deposited at low surface temperature on glass substrate using the DAA microwave technology can find applications for optical devices.

show abstract

Surface morphology and bond characterization of nanocrystalline diamonds grown on tungsten carbide via hot filament chemical vapor deposition

Cited by 8 publications

References 30 publications

Direct Laser Writing of Nanodiamond Films from Graphite under Ambient Conditions

Direct Laser Writing of Nanodiamond Films from Graphite under Ambient Conditions

Effect of Coating Thickness on Abrasion and Cutting Performance of NCD-Coated Ball Endmills on Graphite Machining

Synthesis of High Quality Transparent Nanocrystalline Diamond Films on Glass Substrates Using a Distributed Antenna Array Microwave System

Contact Info

Product

Resources

About