The role of nozzle diameter on the microstructure and abrasion wear resistance of plasma sprayed composite coatings

WC/Co; Composite coating; Plasma spraying; Friction and wear Abstract: WC- Co composite powders were synthesized by direct mechanical grinding in a rotary-vibration mill under 8h, and then analyzed by SEM and XRD. WC and WC/Co composite coatings were prepared by supersonic plasma spraying fine WC-Co composite powders. The wear and friction properties of both coatings were evaluated. The results showed that the wear resistance of the WC/Co composite coating was superior to that of the WC coating. The improvement in wear resistance of the WC/Co composite coating was attributed to its higher fracture toughness and adhesion strength as well as better thermal diffusivity. As for the WC/Co composite coating, the mechanism was mainly adhesion with micro-abrasion and fatigued-induced brittle fracture within splats, and the delamination along splat boundaries only occurred at high load. However, the failure of the WC coating was predominantly detachment of transferred film and brittle fracture within the splats and delamination along splat boundaries, which were enhanced with the increasing load.

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EFFECT OF OXYACETYLENE FLAME REMELTING ON WEAR BEHAVIOUR OF SUPERSONIC AIR-PLASMA SPRAYED NiCrBSi/h-BN COMPOSITE COATINGS

Surface Review and Letters ◽

10.1142/s0218625x17500834 ◽

2016 ◽

Vol 24 (06) ◽

pp. 1750083 ◽

Cited By ~ 3

Author(s):

N. N. ZHANG ◽

D. Y. LIN ◽

B. HE ◽

G. W. ZHANG ◽

Y. ZHANG ◽

...

Keyword(s):

Wear Resistance ◽

Composite Coatings ◽

Alloy Coating ◽

Wear Behaviour ◽

Air Plasma ◽

X Ray ◽

Wear And Corrosion ◽

Before And After ◽

Higher Temperature ◽

Plasma Sprayed

NiCrBSi alloy coatings are widely used in wear and corrosion protection at higher temperature. As a primary hard phase forming element, B element can effectively improve the coating hardness. In this study, the low coefficient of friction of BN with three ratios (10%, 20%, and 30%) was added in order to reduce the wear rate and provide additional B element. The NiCrBSi/h-BN composite coatings were successfully prepared on a cast-iron substrate using supersonic air-plasma spray technology. The phase constitution, microstructure characterization, and microhardness of the coatings before and after oxyacetylene flame remelting were investigated by means of scanning electron microscope (SEM), X-ray diffraction, and energy dispersive analysis of X-ray techniques, respectively. The wear resistance of composite coatings was also tested in this paper. It was found that the microstructure was well refined by remelting treatment and this was beneficial for the adherence between the coating and the substrate, which was nearly 33[Formula: see text]MPa. The wear resistance of the NiCrBSi alloy coating was also improved with the increasing component of h-BN in remelted samples. When the h-BN content reached 30%, the friction coefficient decreased to 0.38 for the remelted coating. The effect of the remelting process on the anti-abrasive property and extension of the material’s wear life was quite important.

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Abrasive Wear Resistance of Plasma-Sprayed Glass-Composite Coatings

Thermal Spray 2000: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2000p0977 ◽

2000 ◽

Author(s):

D.T. Gawne ◽

Z. Qiu ◽

T. Zhang ◽

Y. Bao ◽

K. Zhang

Keyword(s):

Wear Resistance ◽

Composite Structure ◽

Composite Coatings ◽

Thermal Spraying ◽

Secondary Phase ◽

Ceramic Matrix ◽

Scratch Resistance ◽

Abrasive Wear Resistance ◽

Glass Composite ◽

Plasma Sprayed

Abstract A ball-milled mixture of glass and alumina powders has been plasma sprayed to produce alumina-glass composite coatings. The coatings have the unique advantage of a melted ceramic secondary phase parallel to the surface in an aligned platelet composite structure. The alumina raises the hardness from 300HV for pure glass coatings to 900HV for a 60wt% alumina-glass composite coating. The scratch resistance increases by a factor of three and the wear resistance by a factor of five. The glass wears by the formation and intersection of cracks. The alumina wears by fine abrasion and supports most of the sliding load. The wear resistance reached a plateau at 40-50vol% alumina, which corresponds to the changeover from a glass to a ceramic matrix. Keywords: glass composite coatings, wear, thermal spraying

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Phase Transformation-Induced Improvement in Hardness and High-Temperature Wear Resistance of Plasma-Sprayed and Remelted NiCrBSi/WC Coatings

Metals ◽

10.3390/met10121688 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1688

Author(s):

Jin Sha ◽

Liang-Yu Chen ◽

Yi-Tong Liu ◽

Zeng-Jian Yao ◽

Sheng Lu ◽

...

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Composite Coating ◽

Composite Coatings ◽

Hardness Test ◽

Wear Volume ◽

Dispersion Strengthening ◽

High Temperature Wear ◽

Nicrbsi Coating ◽

Plasma Sprayed

The remelting method is introduced to improve the properties of the as-sprayed NiCrBSi coatings. In this work, tungsten carbide (WC) was selected as reinforcement and the as-sprayed and remelted NiCrBSi/WC composite coatings were investigated by X-ray diffraction, scanning electron microscopy, hardness test and tribology test. After spraying, WC particles are evenly distributed in the coating. The remelting process induced the decarburizing reaction of WC, resulting in the formation of dispersed W2C. The dispersed W2C particles play an important role in the dispersion strengthening. Meanwhile, the pores and lamellar structures are eliminated in the remelted NiCrBSi/WC composite coating. Due to these two advantages, the hardness and the high-temperature wear resistance of the remelted NiCrBSi/WC composite coating are significantly improved compared with those with an as-sprayed NiCrBSi coating; the as-sprayed NiCrBSi coating, as-sprayed NiCrBSi/WC composite coating and remelted NiCrBSi/WC composite coating have average hardness of 673.82, 785.14, 1061.23 HV, and their friction coefficients are 0.3418, 0.3261, 0.2431, respectively. The wear volume of the remelted NiCrBSi/WC composite coating is only one-third of that of the as-sprayed NiCrBSi coating.

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The Role of Metastable Austenite for Improving Abrasion Wear Resistance of 150KhNML Perlite Steel

Steel in Translation ◽

10.3103/s0967091221080039 ◽

2021 ◽

Vol 51 (8) ◽

pp. 576-581

Author(s):

M. A. Filippov ◽

M. S. Khadyev ◽

N. N. Kudryashova ◽

V. A. Sharapova ◽

S. O. Morozov

Keyword(s):

Wear Resistance ◽

Metastable Austenite ◽

Abrasion Wear

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Microstructure and Properties of Atmospheric Plasma Sprayed (Al,Cr)2O3–TiO2 Coatings from Blends

Journal of Thermal Spray Technology ◽

10.1007/s11666-021-01289-6 ◽

2021 ◽

Author(s):

Maximilian Grimm ◽

Susan Conze ◽

Lutz-Michael Berger ◽

Rico Drehmann ◽

Thomas Lampke

Keyword(s):

Solid Solution ◽

Wear Resistance ◽

Sliding Wear ◽

Atmospheric Plasma ◽

Coating Properties ◽

High Corrosion Resistance ◽

Abrasion Wear ◽

Small Change ◽

Plasma Sprayed ◽

Insulating Properties

AbstractCoatings prepared from chromia-rich (Al,Cr)2O3 solid solution (ss) feedstock powders are intended to improve the properties of Cr2O3 coatings, but are rarely studied so far. In this work, the processability of a commercial (Al,Cr)2O3 solid solution (ss) powder containing 78 wt.% Cr2O3 by atmospheric plasma spraying (APS), the corresponding coating microstructures and properties were investigated. Possible further improvements were expected by blending with 2, 23 and 54 wt.% TiOx powder. For comparison, plain Cr2O3 and TiOx coatings were studied as well. The microstructures were analyzed using SEM, EDS and XRD measurements. Hardness (HV0.3) was measured, as well as the dry unidirectional sliding wear resistance and the abrasion wear resistance (ASTM G65). Moreover, the corrosion and electrical insulating properties were measured. The (Al,Cr)2O3 ss showed only a small change of the composition, and the formation of γ-Al2O3, as found for alumina-rich (Al,Cr)2O3 ss powders, was avoided. Compared to the plain chromia coating, some improvements of the processability and coating properties for the ss (Al,Cr)2O3 coating were found. The most balanced coating performance was achieved by blending the ss (Al,Cr)2O3 with 2 wt.% TiOx, as this coating showed both a high sliding and abrasion wear resistance, in combination with a high corrosion resistance.

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