Effect of the composition of composite powders on the wear resistance of plasma-sprayed coatings

AbstractComposite particles destined to build plasma sprayed coatings, are prepared by the mechanofusion process (MF). These particles consist of a stainless steel core particle coated by finer particles of alumina. Changes induced by the MF process are monitored by SEM, DRX, and laser granulometry, revealing that the dry particle coating process is governed by agglomeration and rolling phenomena. Simultaneously, the MF performance is controlled by the operating parameters such as the compression gap, the mass ratio of host to guest particle, and the powder input rate. The mechanical energy input leads to a nearly rounded shape of the final composite particles; however, no formation of new phases or components decomposition is detected by XRD analysis. The resulting composite powder features optimal characteristics, concerning particle shape and phases distribution, to be plasma sprayed in air.

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Wear resistance of plasma-sprayed coatings of powdered pg-sr-type alloys in a hydroabrasive medium

Powder Metallurgy and Metal Ceramics ◽

10.1007/bf00559734 ◽

1993 ◽

Vol 32 (1) ◽

pp. 50-54

Author(s):

V. G. Demidov

Keyword(s):

Wear Resistance ◽

Plasma Sprayed Coatings ◽

Plasma Sprayed ◽

Sprayed Coatings

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Novel Zro2-Mullite Composites Produced by Plasma Spraying

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

10.31399/asm.cp.itsc1998p1233 ◽

1998 ◽

Author(s):

K.A. Khor ◽

Y. Li

Keyword(s):

Plasma Spraying ◽

Structural Integrity ◽

Plasma Jet ◽

Distilled Water ◽

Composite Powders ◽

Plasma Flame ◽

Amorphous Phases ◽

Plasma Sprayed Coatings ◽

Plasma Sprayed ◽

Sprayed Coatings

Abstract Zirconia can induce enhanced fracture toughness to a number of ceramics when introduced as a reinforcement either in the form of particulates, dispersed phase or whiskers because of its unique tetragonal-monoclinic (t-*m) transformation. This paper presents the preparation of Zr0 2 reinforced mullite by plasma spraying a mixtures of zircon and alumina. The dissociation of zircon into zirconia and silica in a plasma flame is well-known. Pre-mixed powders of zircon and alumina are injected into a dc plasma jet. The plasma sprayed particles are collected in distilled water and analyzed. The results indicate that the plasma sprayed powders consist of zirconia, zircon and alumina. It was found that fine, mostly amorphous and chemically homogeneous composite powders can be obtained by ball milling and plasma spraying. Recrystallization of amorphous phases and formation of mullite occurred at about 1000 °C in plasma sprayed powders. This value is more than 500 °C lower than the formation of mullite in as-milled powders. Uniform coatings with good structural integrity were obtained by plasma spraying. The amount of amorphous phases was much higher in plasma sprayed coatings than in spheroidized powders, and the relative quantity of mullite in coatings after heat treatment is about 4 times as much as that obtained in the spheroidized powders.

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FORMATION OF FUNCTIONAL PLASMA SPRAYED COATINGS WITH COMPLEX OF IMPROVED PHYSICAL, MECHANICAL AND OPERATIONAL PROPERTIES

POWER ENGINEERING economics technique ecology ◽

10.20535/1813-5420.1.2021.242179 ◽

2021 ◽

pp. 74-80

Author(s):

А. Karpechenko ◽

M. Bobrov

Keyword(s):

Wear Resistance ◽

Bond Strength ◽

Electric Pulse ◽

Experimental Studies ◽

Maximum Level ◽

Surface Plastic ◽

Shot Blasting ◽

Plasma Sprayed Coatings ◽

Plasma Sprayed ◽

Sprayed Coatings

The possibility of increasing the complex of physical, mechanical and operational properties of plasma sprayed coatings from powders of the PG-19M-01 and PRH18N9 grades due to the electric pulse effect on the heterophase high-temperature flow during spraying and next surface plastic deformation of the deposited coatings by shot blasting has been investigated. It is shown that shot blasting provides the formation of a hardening layer with a thickness of up to 180...200 μm, while the maximum level of microhardness is observed at a depth of about 60 μm. The microhardness of the coating from PG-19M-01 powder at the point of maximum hardening increases by 35%; steel coatings from PR-H18N9 powder – by 48% compared to the state after spraying. Experimental studies of the effect of this treatment on the bond strength and wear resistance of the obtained coatings have been carried out. It is shown that after shot-blasting the bond strength of the coatings decreases by 10...15%, and the wear resistance increases by 32...38%.

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