scholarly journals Superhard Coating Materials

MRS Bulletin ◽  
2003 ◽  
Vol 28 (3) ◽  
pp. 164-168 ◽  
Author(s):  
Yip-Wah Chung ◽  
William D. Sproul
Keyword(s):  
Protective Coatings ◽  
Cubic Boron Nitride ◽  
Chemical Vapor ◽  
Hard Coatings ◽  
Nanometer Scale ◽  
Coating Materials ◽  
Nanocomposite Thin Films ◽  
Nitride Coatings ◽  
Hardness Values ◽  
Superhard Coatings

Abstract“Superhard” coating materials are defined by hardness values that exceed 40 GPa. In this issue of MRS Bulletin, we focus on noncarbon-based superhard coatings, with the exception of a review of carbon nitride (CN) materials. Nanometer-scale multilayered nitride coatings were the first to show the superhard property, and these coatings have quickly made their way into industry as protective coatings for cutting-tool operations. Nanocomposite thin films also exhibit superhardness, and some of these materials have hardnesses approaching that of diamond. Cubic boron nitride (c-BN), which is naturally superhard, has proven very difficult to deposit at thicknesses exceeding 0.1 μm, but it is now reported that chemical vapor deposition techniques based on fluorine chemistries can produce c-BN films up to 20 μm thick. The search to produce cubic β-CN has led to the development of noncubic, fullerene-like forms of CN that are both hard and elastic, a very interesting combination of properties that has already been put to use in the hard-disk industry. Overall, the development of hard and superhard coatings during the past 20 years has been remarkable. We have progressed from trying (and often failing) to deposit hard coatings to now designing new nanometer-scale multilayered and nanocomposite coatings that exhibit excellent hardness properties and other high-performancecharacteristics.

Growth, Structure, and Mechanical Properties of Pulsed Laser Deposited TiN/TiB2 Microlaminates

1996 ◽  
Vol 436 ◽  
Author(s):  
Ashok Kumar ◽  
R. B. Inturi ◽  
U. Ekanayake ◽  
H. L. Chan ◽  
J. A. Barnard
Keyword(s):  
Mechanical Properties ◽  
Protective Coatings ◽  
Pulsed Laser ◽  
Single Layer ◽  
High Hardness ◽  
Hard Coatings ◽  
High Melting Point ◽  
Wide Range ◽  
Hardness Values

AbstractHard coatings of TiN and TiB2 have many interesting properties such as high thermal and electrical conductivity, high melting point, good thermodynamic stability and combination of these properties make them an interesting prospect for a wide range of tribological and electronic applications. It is understood that artificial multilayer structures have shown anamolously high hardness and modulii making them likely candidate for future protective coatings. Single layer of TiN, TiB2, and TiB2/TiN microlaminates coatings with varying thickness have been deposited on Si (100) and oxidized Si(111) substrates by in-situ pulsed laser deposition method. These films are deposited at 10 Hz repetition rate of excimer laser (λ = 248 nm). Our preliminary results show that elastic modulii and hardness values of multilayered coatings are superior than monolithic coatings of either of the two constituent materials. The coatings have been characterized by X-ray diffiractometer and AFM techniques. Detailed results have been presented to correlate the effect of microlaminate thickness on the mechanical properties.

Coating Materials

2021 ◽  
pp. 1-30
Author(s):  
Mintu Maan Dutta ◽  
Mridusmita Goswami
Keyword(s):  
Vapor Phase ◽  
Uv Light ◽  
Protective Coatings ◽  
Sol Gel ◽  
Chemical Vapor ◽  
Commercial Application ◽  
Coating Materials ◽  
Vapor Phase Deposition ◽  
Anticorrosion Coatings ◽  
Beam Surface

The ever-growing interest in nanocoating and its enthralling protective properties makes it a very capable candidate for next generation protecting systems. The future of these special nanocoating markets will be expanding in different industries such as marine, building, and defense. The main purpose of coatings involves the use of thin films (nanoscale dimensions) that are applied to the surface of materials, which improve the material functionalities. Some of the improved functionalities include anti-corrosion, easy-to-clean (anti-graffiti), anti-icing, anti-fogging, anti-fouling, etc. Some of the common techniques used for nanocoating are chemical vapor phase deposition, physical vapor phase deposition, Sol-gel methods, electro-spark deposition, electrochemical deposition, and laser beam surface treatment. Commercial application of nanocoating nanotechnology includes self-cleaning coatings, depolluting coatings, ultraviolet (UV) light protective coatings, anticorrosion coatings, thermal resistance, anti-fouling coatings, and anti-graffiti coatings.

Microstructural characterization of sol-gel coating on PET films

1994 ◽  
Vol 52 ◽  
pp. 886-887
Author(s):  
R. T. Chen ◽  
R.A. Norwood
Keyword(s):  
Ion Beam ◽  
Sol Gel ◽  
Industrial Applications ◽  
Hard Coatings ◽  
Nanometer Scale ◽  
Ion Beam Sputtering ◽  
Process Technology ◽  
Refractive Index Measurement ◽  
Organically Modified ◽  
Pet Films

Sol-gel processing has been used to control the structure of a material on a nanometer scale in preparing advanced ceramics and glasses. Film coating using the sol-gel process was also found to be a viable process technology in applications such as optical, porous, antireflection and hard coatings. In this study, organically modified silicate (Ormosil) coatings are applied to PET films for various industrial applications. Sol-gel materials are known to exhibit nanometer scale structures which havepreviously been characterized by small-angle X-ray scattering (SAXS), neutron scattering and light scattering. Imaging of the ultrafine sol-gel structures has also been performed using an ultrahigh resolution replica/TEM technique. The objective of this study was to evaluate the ultrafine structures inthe sol gel coatings using a direct imaging technique: atomic force microscopy (AFM). In addition, correlation of microstructures with processing parameters, coating density and other physical properties will be discussed.The materials evaluated are organically modified silicate coatings on PET film substrates. Refractive index measurement by the prism coupling method was used to assess density of the sol-gel coating.AFM imaging was performed on a Nanoscope III AFM (by Digital Instruments) using constant force mode. Solgel coating samples coated with a thin layer of Ft (by ion beam sputtering) were also examined by STM in order to confirm the structures observed in the contact type AFM. In addition, to compare the previous results, sol-gel powder samples were also prepared by ultrasonication followed by Pt/Au shadowing and examined using a JEOL 100CX TEM.

Dynamic consolidation of cubic boron nitride and its admixtures

1988 ◽  
Vol 3 (5) ◽  
pp. 1010-1020 ◽  
Author(s):  
Hua Tan ◽  
Thomas J. Ahrens
Keyword(s):  
Particle Size ◽  
Boron Nitride ◽  
Cubic Boron Nitride ◽  
Sem Analysis ◽  
Model Calculations ◽  
Boron Nitride Powder ◽  
Dynamic Consolidation ◽  
Consolidation Model ◽  
Heating Model ◽  
Hardness Values

Cubic boron nitride (C–BN)' powders admixed with graphite-structured boron nitride powder (g-DN), silicon carbide whisker (SCW), or silicon nitride whisker (SNW) were shock compacted to pressures up to 22 GPa. Unlike previous work with diamond and graphite [D. K. Potter and T. J. Ahrens, J. Appl. Phys. 63, 910 (1987) it was found that the addition of g-BN inhibited dynamic consolidation. Good consolidation was achieved with a 4–8 μm particle size C–BN powder admixed with 15 wt.% SNW or 20 wt.% SCW whereas a 37–44 μm particle size C–BN mixture was only poorly consolidated. Scanning electron microscopy (SEM) analysis demonstrates that SCW and SNW in the mixtures were highly deformed and indicated melt textures. A skin heating model was used to describe the physics of consolidation. Model calculations are consistent with SEM analysis images that indicate plastic deformation of SCW and SNW. Micro-Vickers hardness values as high as 50 GPa were obtained for consolidated C–BN and SNW mixtures. This compares to 21 GPa for single-crystal Al2O3 and 120 GPa for diamond.

scholarly journals Thermally Assisted Machine Hammer Peening of Arc-Sprayed ZnAl-Based Corrosion Protective Coatings

2021 ◽  
Vol 5 (4) ◽  
pp. 109
Author(s):  
Andreas Wirtz ◽  
Mohamed Abdulgader ◽  
Michael P. Milz ◽  
Wolfgang Tillmann ◽  
Frank Walther ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Protective Coatings ◽  
Fatigue Behavior ◽  
Wind Waves ◽  
Offshore Wind ◽  
Coating Materials ◽  
Corrosive Media ◽  
Machine Hammer Peening ◽  
Hammer Peening ◽  
Compressive Residual Stresses

Structural elements of offshore facilities, e.g., offshore wind turbines, are subject to static and dynamic mechanical and environmental loads, for example, from wind, waves, and corrosive media. Protective coatings such as thermal sprayed ZnAl coatings are often used for protection, mainly against corrosive stresses. The Machine Hammer Peening (MHP) process is an innovative and promising technique for the post-treatment of ZnAl coating systems that helps reducing roughness and porosity and inducing compressive residual stresses. This should lead to an enhancement of the corrosion fatigue behavior. In this paper, the effect of a thermally assisted MHP process was investigated. The softening of the coating materials will have a direct effect on the densification, residual porosity and the distribution of cracks. The investigation results showed the influence of thermally assisted MHP on the surface properties, porosity, residual stresses, and hardness of the post-treated coatings. The best densification of the coating, i.e., the lowest porosity and roughness and the highest compressive residual stresses, were achieved at a process temperature of 300 °C. A further increase in temperature on the other hand caused a higher porosity and, in some cases, locally restricted melting of the coating and consequently poorer coating properties.

Twin structures of rhombohedral and cubic boron nitride prepared by chemical vapor deposition method

2003 ◽  
Vol 12 (3-7) ◽  
pp. 1138-1145 ◽  
Author(s):  
Takeo Oku ◽  
Kenji Hiraga ◽  
Toshitsugu Matsuda ◽  
Toshio Hirai ◽  
Makoto Hirabayashi
Keyword(s):  
Chemical Vapor Deposition ◽  
Boron Nitride ◽  
Vapor Deposition ◽  
Cubic Boron Nitride ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Deposition Method

Deposition of TiN, TiC, and DLC Coatings by PACVD

2018 ◽  
pp. 381-402
Author(s):  
Mahboobeh Azadi
Keyword(s):  
Vapor Deposition ◽  
Materials Science ◽  
Chemical Vapor ◽  
Industrial Applications ◽  
Hard Coatings ◽  
Diamond Like Carbon ◽  
Functional Coatings ◽  
Dlc Coatings ◽  
Medical Instruments ◽  
Source Of Information

In this chapter, the author studied about titanium nitride (TiN), titanium carbide (TiC), diamond like carbon (DLC) single and multilayer coatings that utilize in harsh environments. These hard coatings were usually produced by the plasma assisted chemical vapor deposition (PACVD) method as a modern technique. PACVD is used to deposit thin coatings for different usages such as computer disc drives, automobile and aerospace parts, surgical/medical instruments and the food industry. The author tried to delineate the state of the performance of different coating systems and layer characteristics that suitable either for laboratory -scales or industrial applications. Mechanical features of these coatings contain the hardness, the toughness, the wear resistance and structural properties that were perused. Consequently, this chapter offers a source of information for those who want to familiarize with the knowledge in the area of materials science of functional coatings that was produced by new plasma-based technologies.

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