Contact damage investigation of CVD carbonitride hard coatings deposited on cemented carbides

The plasma-assisted chemical vapor deposition (PACVD) technique has shown many advantages in applications, where thin coatings with superior wear properties are demanded, especially for geometrically complex parts. In this study, multilayered gradient TiBN coatings that were deposited on nanostructured cemented carbides by the PACVD method were investigated. Nanostructured samples of cemented carbides with the addition of 5 and 15 wt.% Co were sintered by the hot isostatic pressing, sinter-HIP technique. Surface preparation was conducted on samples in order to enable maximum coating adhesion. Tests that were conducted on produced samples aimed to investigate the mechanical and physical properties of coated samples. These tests included nanoindentation, surface layer characterization, and coating adhesion evaluation while using the Rockwell and scratch test. The obtained results confirmed that the PACVD process can be utilized for applying thin hard coatings to nanostructured cemented carbides that are produced by the sinter HIP process, resulting in a base material/ coating system that exhibits excellent physical and mechanical properties. The results presented in this paper give a valuable contribution to the research of TiBN coating systems and their potential for application under heavy wear conditions.

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Design of New Gradient Cemented Carbides and Hard Coatings Through Ceramic Genome

Ceramic Transactions Series - High Temperature Ceramic Matrix Composites 8 ◽

10.1002/9781118932995.ch1 ◽

2014 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Weibin Zhang ◽

Yong Du ◽

Li Chen ◽

Yingbiao Peng ◽

Peng Zhou ◽

...

Keyword(s):

Hard Coatings ◽

Cemented Carbides

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Corrosion-induced changes on Hertzian contact damage in cemented carbides

International Journal of Refractory Metals and Hard Materials ◽

10.1016/j.ijrmhm.2020.105334 ◽

2020 ◽

Vol 92 ◽

pp. 105334

Author(s):

Y.F. Zheng ◽

G. Fargas ◽

O. Lavigne ◽

E. Roitero ◽

L. Llanes

Keyword(s):

Hertzian Contact ◽

Cemented Carbides ◽

Contact Damage ◽

Induced Changes

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Improvement of adhesion force of hard coatings to cemented carbides by laser heating

The Journal of Adhesion ◽

10.1080/00218464.2019.1671191 ◽

2019 ◽

Vol 96 (1-4) ◽

pp. 33-47

Author(s):

M.J. Kupczyk

Keyword(s):

Laser Heating ◽

Adhesion Force ◽

Hard Coatings ◽

Cemented Carbides

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Estimation of possibilities of increase of adhesion of hard coatings to cutting edges by its laser heating

Mechanik ◽

10.17814/mechanik.2018.8-9.106 ◽

2018 ◽

Vol 91 (8-9) ◽

pp. 680-682

Author(s):

Maciej Jan Kupczyk

Keyword(s):

Critical Load ◽

Laser Heating ◽

Adhesion Force ◽

Scratch Test ◽

Hard Coatings ◽

Cemented Carbides

Evaluation of the possibilities of increasing of adhesion force (values of the critical load measured by the scratch test) of hard coatings to cutting edges made of cemented carbides by their laser heating was a purpose of researches.

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X-Ray diffraction characterization of pre-treated cemented carbides for optimizing adhesion strength of sputtered hard coatings

Surface and Coatings Technology ◽

10.1016/s0257-8972(01)01282-8 ◽

2001 ◽

Vol 142-144 ◽

pp. 1100-1104 ◽

Cited By ~ 7

Author(s):

H.K. Tönshoff ◽

H. Seegers

Keyword(s):

Adhesion Strength ◽

Hard Coatings ◽

Cemented Carbides ◽

X Ray Diffraction ◽

X Ray

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Microstructure of Electro-Eroded Cemented Carbide Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101165 ◽

1968 ◽

Vol 26 ◽

pp. 284-285

Author(s):

V. N. Filimonenko ◽

M. H. Richman ◽

J. Gurland

Keyword(s):

Surface Layer ◽

Cobalt Content ◽

Cemented Carbides ◽

Face Centered Cubic ◽

X Ray Diffraction ◽

Metallographic Examination ◽

Standard Procedures ◽

Face Centered ◽

Diamond Paste ◽

Plastic Carbon

The high temperatures and pressures that are found in a spark gap during electrical discharging lead to a sharp phase transition and structural transformation in the surface layer of cemented carbides containing WC and cobalt. By means of X-ray diffraction both W2C and a high-temperature monocarbide of tungsten (face-centered cubic) were detected after electro-erosion. The W2C forms as a result of the peritectic reaction, WC → W2C+C. The existence and amount of the phases depend on both the energy of the electro-spark discharge and the cobalt content. In the case of a low-energy discharge (i.e. C=0.01μF, V = 300v), WC(f.c.c.) is generally formed in the surface layer. However, at high energies, (e.g. C=30μF, V = 300v), W2C is formed at the surface in preference to the monocarbide. The phase transformations in the surface layer are retarded by the presence of larger percentages of cobalt.Metallographic examination of the electro-eroded surfaces of cemented carbides was carried out on samples with 5-30% cobalt content. The specimens were first metallographically polished using diamond paste and standard procedures and then subjected to various electrical discharges on a Servomet spark machining device. The samples were then repolished and etched in a 3% NH4OH electrolyte at -0.5 amp/cm2. Two stage plastic-carbon replicas were then made and shadowed with chromium at 27°.

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Microstructural characterization of sol-gel coating on PET films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172164 ◽

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.

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