The structure and properties of a hard alloy coating deposited by high-velocity pulsed plasma jet onto a copper substrate

Abstract Ceramic nanostructured coatings with intermediate thicknesses between 10 and 100 µm exhibit improved thermal and mechanical properties for thermal barrier coatings or wear resistant coatings. Such coatings comply with the technical requirements of aeronautical and automotive applications. This implies to develop deposition processes with high throughput and deposition rates promoting the formation of nanostructured coatings. The use of a liquid phase as a carrier medium of nanoparticles or of solution precursors has been shown to be of major interest when being injected within a thermal plasma jet. The as-sprayed materials can form ceramic nanostructured coatings provided the liquid injection encompassing the physicochemical properties of liquid and its injection method copes with the plasma properties. Especially the repeatability of the interaction phenomena between the liquid phase and the arc jet has a key role in the efficiency deposition so that some research efforts are devoted to stabilize the arc while a liquid jet is continuously injected within the plasma. Alternatively a pulsed arc plasma jet can be generated and associated with a time-phased injection of droplets. This paper presents the different issues related to the arc plasma properties produced by direct plasma torches including the arc instabilities and their influence on plasma/liquid interaction mechanisms leading to the formation of nanomaterials. A focus is made on pulsed plasma spraying associated with a synchronized injection of microsized droplets by means of an inkjet printing method.

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Experimental demonstration of Martian soil simulant removal from a surface using a pulsed plasma jet

Review of Scientific Instruments ◽

10.1063/1.4915498 ◽

2015 ◽

Vol 86 (3) ◽

pp. 033509 ◽

Cited By ~ 6

Author(s):

C. M. Ticoş ◽

A. Scurtu ◽

D. Toader ◽

N. Banu

Keyword(s):

Plasma Jet ◽

Pulsed Plasma ◽

Experimental Demonstration ◽

Martian Soil

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High Velocity Pulsed Plasma Thermal Spray

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

10.31399/asm.cp.itsc2000p0669 ◽

2000 ◽

Author(s):

F.D. Witherspoon ◽

D.W. Massey ◽

R.W. Kincaid ◽

G.C. Whichard ◽

T.A. Mozhi

Keyword(s):

Thermal Spray ◽

High Velocity ◽

Vacuum Chamber ◽

Thermal Environment ◽

Diagnostic System ◽

Inert Atmosphere ◽

Pulsed Plasma ◽

Combustible Gases ◽

Accelerated Particles

Abstract The quality and durability of coatings produced by virtually all thermal spray techniques could be improved by increasing the velocity with which coating particles impact the substrate. Additionally, better control of the chemical and thermal environment seen by the particles during flight is crucial to the quality of the coating. A high velocity thermal spray device is under development through a BMDO SBIR project which provides significantly higher impact velocity for accelerated particles than is currently available with existing thermal spray devices. This device utilizes a pulsed plasma as the accelerative medium for powders introduced into the barrel. Recent experiments using a Control-Vision diagnostic system showed that the device can accelerate stainless steel and WC-Co powders to velocities ranging from 1500 to 2200 m/s. These high velocities are accomplished without the use of combustible gases, and without the need of a vacuum chamber, while maintaining an inert atmosphere for the particles during acceleration. The high velocities corresponded well to modeling predictions, and these same models suggest that velocities as high as 3000 m/s or higher are possible.

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A Sub-microsecond Pulsed Plasma Jet for Endodontic Biofilm Disinfection

Plasma for Bio-Decontamination, Medicine and Food Security - NATO Science for Peace and Security Series A: Chemistry and Biology ◽

10.1007/978-94-007-2852-3_14 ◽

2011 ◽

pp. 179-190 ◽

Cited By ~ 2

Author(s):

Chunqi Jiang ◽

Christoph Schaudinn ◽

David E. Jaramillo ◽

Martin A. Gundersen ◽

J. William Costerton

Keyword(s):

Plasma Jet ◽

Pulsed Plasma

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Optimizing the Substrate Preheating Process of High Velocity Oxygen Fuel Cobalt-Based Alloy Coating on Alloyed and Carbon Steels Mechanical Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.929.142 ◽

2018 ◽

Vol 929 ◽

pp. 142-149 ◽

Cited By ~ 1

Author(s):

Myrna Ariati Mochtar ◽

Wahyuaji Narottama Putra ◽

Raditya Perdana Rachmansyah

Keyword(s):

Wear Resistance ◽

High Velocity ◽

Alloy Coating ◽

Carbon Steels ◽

Surface Heating ◽

Initial Surface ◽

High Velocity Oxygen Fuel ◽

Alternative Material ◽

Substrate Preheating ◽

Oxygen Fuel

Tube boiler operating condition initiates common problems that can occur as a problem in the wear resistance material. It leads to a decreased function of the material so that it is necessary to repair or replacement. High Velocity Oxygen Fuel (HVOF) is regarded as one of the effective methods to increase the wear resistance of the material. In this study, the materials were ASTM SA213-T91 as a material commonly used for boiler tube and JIS G 3132 SPHT-2 as an alternative material. In the early stages, both of specimens were given initial surface heating with temperature variations 0, 50, 100 and 150oC. The materials were then coated with Stellite-1 using HVOF method. The material were then characterized for the microstructure, porosity, hardness distribution, and wear resistant. The results showed that the coating Stellite-1 as a top coat with HVOF method can improve the performance of the material. Microhardness increases from 220 HV to 770 HV on ASTM SA213-T91, while on the substrate JIS G 3132 SPHT-2 the microhardness increased from 120 HV to 750 HV. Better wear resistance was achieved with increasing preheating [1]. Wear resistance of the materials increased from the range 3.69x10-7at 0°C preheating up to 0.89x10-7on a specimen with initial surface heating 150oC. Porosity also decreases with the increasing preheating temperature.

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