Interaction of particles with carrier gas in HVOF spraying systems

Kadyrov, E.; Evdokimenko, Yu. I.; Kisel, V. M.; Kadyrov, V. Kh.; Worzala, F. J.

doi:10.1007/bf02658984

Cited by 10 publications

(17 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The effect of different parameters such as equivalent ratio and total flow rate on the gas and particle behavior is discussed comprehensively in the literature (see [37,[60][61][62][70][71][72][73][74]). In a remarkable work, Cheng et al [71] revealed that the pressure inside the nozzle, the shock diamonds' spacing, the free jet velocity and temperature, and the mass flow rate at the nozzle exit increase as the total inlet gas flow rate enhances (the ratio of fuel (propylene), air, oxygen, and nitrogen was supposed to be constant) (similar results in [61,62,74]).…”

Section: Operating Conditions Effectsmentioning

confidence: 99%

See 1 more Smart Citation

A Comprehensive Review on Fluid Dynamics and Transport of Suspension/Liquid Droplets and Particles in High-Velocity Oxygen-Fuel (HVOF) Thermal Spray

2015

View full text Add to dashboard Cite

Abstract:In thermal spraying processes, molten, semi-molten, or solid particles, which are sufficiently fast in a stream of gas, are deposited on a substrate. These particles can plastically deform while impacting on the substrate, which results in the formation of well-adhered and dense coatings. Clearly, particles in flight conditions, such as velocity, trajectory, temperature, and melting state, have enormous influence on the coating properties and should be well understood to control and improve the coating quality. The focus of this study is on the high velocity oxygen fuel (HVOF) spraying and high velocity suspension flame spraying (HVSFS) techniques, which are widely used in academia and industry to generate different types of coatings. Extensive numerical and experimental studies were carried out and are still in progress to estimate the particle in-flight behavior in thermal spray processes. In this review paper, the fundamental phenomena involved in the mentioned thermal spray techniques, such as shock diamonds, combustion, primary atomization, secondary atomization, etc., are discussed comprehensively. In addition, the basic aspects and emerging trends in simulation of thermal spray processes are reviewed. The numerical approaches such as Eulerian-Lagrangian and volume of fluid along with their advantages and disadvantages are explained in detail. Furthermore, this article provides a detailed review on simulation studies published to date. OPEN ACCESSCoatings 2015, 5 577

show abstract

Section: Operating Conditions Effectsmentioning

confidence: 99%

“…Kadyrov et al [70] revealed that the particle velocity in the supersonic nozzle was higher than that in the subsonic nozzle. However, the particle temperature in the supersonic nozzle was lower because the particle spent a shorter time in this nozzle.…”

Section: Nozzle Shapementioning

confidence: 99%

A Comprehensive Review on Fluid Dynamics and Transport of Suspension/Liquid Droplets and Particles in High-Velocity Oxygen-Fuel (HVOF) Thermal Spray

2015

View full text Add to dashboard Cite

show abstract

“…The expression above allows for the estimation of required particle acceleration velocity for more moderate heating of particles to prevent undesirable physicochemical transformations. The development of plasma spraying and supersonic flame spraying of coatings has been reported ( Ref 11,[31][32][33][34][35][36]39,[41][42][43][44][45][46][47][48][49][50][51][52][53], and the properties of the coatings produced by these methods are comparable with those of detonation coatings. The HVOF processes similar to the D-gun spraying are based on high-pressure combustion.…”

Section: Introductionmentioning

confidence: 77%

“…In fact, the concept of HVOF spraying has evolved, along with a better understanding of the system, through modeling and measurements ( Ref 28,29,[45][46][47]. Since the first HVOF torch (Jet Kote System) operating at 0.41 MPa, different torches have been designed with operating pressure up to 1.35 MPa (Terojet, Eutectic Castolin, CH) ( Ref 44).…”

Section: Introductionmentioning

confidence: 99%

Influence of Detonation Gun Spraying Conditions on the Quality of Fe-Al Intermetallic Protective Coatings in the Presence of NiAl and NiCr Interlayers

Senderowski

Bojar

2009

J Therm Spray Tech

View full text Add to dashboard Cite

The paper presents results of detailed research of the application of detonation gun (D-gun) spraying process for deposition of Fe-Al intermetallic coatings in the presence of NiAl and NiCr interlayers. A number of D-gun experiments have been carried out with significant changes in spraying parameters which define the process energy levels (changes in volumes of the working and fuel gases, and the distance and frequency of spraying). These changes directly influenced the quality of the coatings. The initial results underlay the choice of the process parameters with the view to obtain the most advantageous of geometric and physical-mechanical properties of the coating material, interlayer and substrate. The metallurgical quality of the coatings was considered by taking into account grain morphology, the inhomogeneity of chemical content and phase structure, the cohesive porosity in the coating volume, and adhesive porosity in the substrate/interlayer/coating boundaries. The surface roughness level was also considered. It was found that the D-gun sprayed coatings are in all cases built with flat lamellar splats. The splats develop from powder particles which are D-gun transformed in their plasticity and geometry. A significant result of the optimization of D-gun spraying parameters is the lack of signs of melting of the material (even in microareas) while the geometry of the subsequently deposited grains is considerably changed and the adhesivity and cohesion of the layers proves to be high. This is considered as an undeniable proof of high plasticity of the D-gun formed Fe-Al intermetallic coating.

show abstract

“…In the thermal spray coating process, a coating material is fed into a heating zone (combustion zone) to become molten or semimolten, and melted particles are then propelled out from the nozzle of the spray gun and projected toward a substrate (40). Before producing a layer on the substrate, individual particles interact with the surrounding atmosphere during flight from the spray gun to the substrate.…”

Section: Thermal Sprayingmentioning

confidence: 99%