Microstructure wear resistance and erosion resistance of plasma-sprayed boride coatings

This paper describes an investigation of nano-Al2O3 powders reinforced ceramic coatings, which has included NiCrAl and Al2O3+13%wt.TiO2 coats pre-produced by atmosphere plasma spraying, implemented by laser sintering. Commercial NiCrAl powders were plasma sprayed onto 45 Steel substrates to give a bond coat with thickness of ∼100μm. The 600μm thick Al2O3+13%wt.TiO2 based coating was also plasma sprayed on top of the NiCrAl bond coat. With 2.5kw continuous wave CO2 laser, nano-Al2O3 ceramic powders were laser sintered on the based Coatings. The micro structure and chemical composition of the modified Al2O3+13%wt.TiO2 coatings were analyzed by such detection devices as scanning electronic microscope (SEM) and x-ray diffraction (XRD). Microhardness, wear resistance and corrosion resistance of the modified coatings were also tested and compared with that of the unmodified. The results show that the crystal grain size of Al2O3 had no obvious growth. In addition, due to the nanostructured Al2O3 ceramic phases, the coatings exhibited higher microhardness, better wear resistance and corrosion resistance than those unmodified counterparts. The complex process of plasma spraying with laser sintering as a potential effective way of the application of ceramic nano materials was also simply discussed and summarized in the end.

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Cavitation Erosion and Sliding Wear of MCrAlY and NiCrMo Coatings Deposited by HVOF Thermal Spraying

Advances in Materials Science ◽

10.2478/adms-2020-0008 ◽

2020 ◽

Vol 20 (2) ◽

pp. 26-38 ◽

Cited By ~ 1

Author(s):

M. Szala ◽

M. Walczak ◽

L. Łatka ◽

K. Gancarczyk ◽

D. Özkan

Keyword(s):

Wear Resistance ◽

Sliding Wear ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Nickel Content ◽

Thermal Spraying ◽

Point Of View ◽

Engineering Practice ◽

Hvof Thermal Spraying ◽

Cavitation Erosion Resistance

AbstractThe investigation into wear resistance is an up-to-date problem from the point of view of both scientific and engineering practice. In this study, HVOF coatings such as MCrAlY (CoNiCrAlY and NiCoCrAlY) and NiCrMo were deposited on AISI 310 (X15CrNi25-20) stainless steel substrates. The microstructural properties and surface morphology of the as-sprayed coatings were examined. Cavitation erosion tests were conducted using the vibratory method in accordance with the ASTM G32 standard. Sliding wear was examined with the use of a ball-on-disc tribometer, and friction coefficients were measured. The sliding and cavitation wear mechanisms were identified with the SEM-EDS method. In comparison to the NiCrMo coating, the MCrAlY coatings have lower wear resistance. The cavitation erosion resistance of the as-sprayed M(Co,Ni)CrAlY coatings is almost two times lower than that of the as-sprayed NiCrMoFeCo deposit. Moreover, the sliding wear resistance increases with increasing the nickel content as follows: CoNiCrAlY < NiCoCrAlY < NiCrMoFeCo. The mean friction coefficient of CoNiCrAlY coating equals of 0.873, which almost 50% exceed those reported for coating NiCrMoFeCo of 0.573. The as-sprayed NiCrMoFeCo coating presents superior sliding wear and cavitation erosion resistance to the as-sprayed MCrAlY (CoNiCrAlY and NiCoCrAlY) coatings.

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Tungsten Carbide Dispersed High Cr-Ni Cast Iron Produced by Plasma Spraying

Materials Science Forum ◽

10.4028/www.scientific.net/msf.891.565 ◽

2017 ◽

Vol 891 ◽

pp. 565-568

Author(s):

Yasuhiro Hoshiyama ◽

Kyouhei Yamaguchi ◽

Hidekazu Miyake

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Tungsten Carbide ◽

Alloy Powder ◽

Treatment Temperature ◽

Heat Treated ◽

Ni Alloy ◽

Low Pressure Plasma ◽

Plasma Sprayed ◽

Carbide Particles

Fe-C-W-Cr-Ni alloy powder in diameter of 32-53 μm made by argon atomization was low-pressure plasma sprayed to produce high Cr-Ni cast iron base deposits with finely dispersed tungsten carbide particles. The as-sprayed deposit produced on a non-cooled substrate was composed of γFe, αFe and carbide. The fine precipitates in the as-sprayed deposit were carbide. With increasing heat treatment temperature up to 1273 K, the carbide particles coarsened. The as-sprayed deposit produced on a non-cooled substrate had higher hardness than the heat-treated deposits. The wear resistance of the as-sprayed deposit produced on a non-cooled substrate was lower than that of heat-treated deposits. The as-sprayed deposit produced on a non-cooled substrate and heat-treated deposits had higher wear resistance than commercial stainless steel.

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Wear Evaluation of Plasma Sprayed Oxide and Carbide Coatings

Thermal Spray 1998: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc1998p0275 ◽

1998 ◽

Author(s):

C. Ding ◽

J. Li ◽

L. Zhang ◽

X. Yu

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Smooth Surface ◽

Surface Film ◽

Protective Film ◽

Wear Coefficient ◽

Sio2 Glass ◽

Carbide Coatings ◽

Wear Evaluation ◽

Plasma Sprayed

Abstract Wear of plasma sprayed Cr2O3 TiO2, Cr3C2-NiCr and WC-Co coatings have been evaluated with a block-on-ring arrangement under dry and lubricated conditions. The results indicated that the wear of the coatings was interpreted in term of subsurface grain fracture which was related to the special microstructure of the coatings such as size, shape and distribution of pore as well as crack. Among the four kinds of coating, Cr2O3 coating possesses the lowest wear coefficient. Water accelerated cracking and fracturing and deteriorated the wear resistance of both Cr3C2-NiCr and TiO2 coatings. Ethanol reduced the wear of Cr3C2-NiCr coating, which was attributed to the formation of a smooth surface film mainly consisting of Cr2O3. Wear of Cr2O3, coating against an Al2O3 ball at high temperature has been also produced. The wear of Cr2O3 coating against Al2O3 ceramics decreased with increase in temperature and load. The reaction between Cr2O3 coating and Al2O3, ceramics at high temperature and the formation of a protective film consisting of Cr2O3, Al2O3 and SiO2 glass on the surface of Cr2O3 coating improved the wear resistance of Cr2O3 coating.

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Analysis of Wear Resistance of Borided Steel C45

Materials ◽

10.3390/ma13235529 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5529

Author(s):

Mykhaylo Pashechko ◽

Krzysztof Dziedzic ◽

Jerzy Jozwik

Keyword(s):

Wear Resistance ◽

Wear Surface ◽

Chemical Elements ◽

Substrate Material ◽

High Wear Resistance ◽

Material Research ◽

Specific Pressure ◽

Diffusion Coatings ◽

Boride Coatings ◽

Induced Structure

The wear resistance of diffusion coatings in conditions of specific pressures of 3, 7 and 10 MPa was studied. The boride coatings were prepared by means of diffusion methods using C45 steel as the substrate material. Research on the microstructure and redistribution of chemical elements on wear surface of a borided layer was carried out. It was found that the boride coatings should be used under a specific pressure of 7 MPa. It was found that the wear of friction couple coating of steel C45 under specific pressure of 3 MPa proceeds according to the oxidation wear mechanism, while under specific pressures of 7 and 10 MPa the abrasive wear prevails. The wear-induced segregation of atoms in coatings was studied using secondary mass-spectroscopy method (SIMS). Increased C, O, and B concentrations were noticed at the wear surface on depth from 50 to 2000 Å. The secondary wear-induced structure formation on the wear surface resulted in high wear resistance of diffusion borided coatings.

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