Wire Composition: Its Effect on Metal Disintegration and Particle Formation in Twin-Wire Arc-Spraying Process

In this study, Ni-5wt.%Al coating was fabricated on the 6061-T6 aluminum alloy substrate by twin-wire arc spraying technology. Through different heat treatment process, effect of microstructure and phase structure was studied with different temperature and time. Interface reaction mechanism of alloy coating/substrate and diffusion behavior of elements was discussed. Heat treatment was carried out at 400°C，480°C，550°C and respective for 4h, 24h, 48h. The XRD , SEM and EDS results showed that main phases of Ni-5wt.%Al original coating were composed of Ni solid solution, in addition to a small amount of Al2O3, NiO and Al4Ni3. Phase composition has basically not changed, interface of the coating/substrate occurred diffusion, which was controlled by the diffusion of Al atoms. Intermetallic compounds of NiAl3 and Ni2Al3 were formed in interface of coating/substrate, and interface diffusion area gradually was thickened.

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CFD Study of Particle and Compressible Flow Interaction for a Twin Wire Arc Spraying System

Volume 7: Fluids Engineering ◽

10.1115/imece2019-10101 ◽

2019 ◽

Author(s):

Raymond Faull ◽

Nicole Wagner ◽

Kevin Anderson

Keyword(s):

Plasma Spraying ◽

Gas Flow ◽

Particle Trajectory ◽

Flow Direction ◽

Phase Changes ◽

Particle Flow ◽

Spray Angle ◽

Arc Spraying ◽

Twin Wire Arc Spraying ◽

Wire Arc Spraying

Abstract Plasma spraying is used in various industries for additive manufacturing applications to apply materials onto a workpiece. Such applications could be for the purpose of repair, protection against corrosion, wear-resistance, or enhancing surface properties. One plasma spraying method is the twin wire arc spraying (TWAS) process that utilizes two electrically conductive wires, across which an electric arc is generated at their meeting point. The molten droplets that are created are propelled by an atomizing gas towards a substrate on which the coating is deposited. The TWAS process offers low workpiece heating and high deposition rates at a lower cost compared to other plasma spraying techniques. As the spray angle for this technique is relatively large (15 degree half angle), particles are lost in the process, lowering the yield of deposited material. The motivation of this project was to constrict the particle flow and reduce the loss of particles that are ejected by the spraying torch. Torch nozzles were designed to help the particle trajectory match the axial flow direction of the atomizing gas flow. Simulations using ANSYS FLUENT Computational Fluid Dynamics (CFD) software was utilized to model both the atomizing gas flow and particle flow for a TWAS system. Various nozzle configurations with arc jet angles between 30–75 degrees showed only small effects on gas flow velocity and shape, with no significant variations in particle flow. These results indicate that nozzle configurations are only one factor in determining particle trajectory, and that phase changes and heat transfer need to be considered as well.

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Asymmetric Melting Behavior in Twin Wire Arc Spraying with Cored Wires

Journal of Thermal Spray Technology ◽

10.1007/s11666-008-9269-y ◽

2008 ◽

Vol 17 (5-6) ◽

pp. 974-982 ◽

Cited By ~ 10

Author(s):

W. Tillmann ◽

E. Vogli ◽

M. Abdulgader

Keyword(s):

Melting Behavior ◽

Arc Spraying ◽

Twin Wire Arc Spraying ◽

Wire Arc Spraying ◽

Cored Wires

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Enhanced Copper Coating Properties Obtained by Electric Wire Arc Spraying Process

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

10.31399/asm.cp.itsc2000p0685 ◽

2000 ◽

Author(s):

V. Gourlaouen ◽

E. Verna ◽

P. Beaubien

Keyword(s):

Copper Coating ◽

Compressed Air ◽

Arc Spraying ◽

Coating Process ◽

Coating Properties ◽

Electrical Wire ◽

Wire Arc Spraying ◽

Series Of Experiments ◽

Spraying Process

Abstract Among the different wires used in arc spraying, copper is a material of choice in some applications. Its malleability is used to allow an easy machining procedure after spraying. This article focuses on the limitations of the oxidation of copper during arc spraying and its influence on coating process and properties. The aim of this series of experiments was to improve coating properties of copper sprayed with the electrical wire arc spraying process by substituting compressed air with nitrogen. These experiments show that coating properties, as well as electric wire arc spraying process, are strongly influenced by the gas employed as the atomising element.

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