THE EFFECT OF CARBURIZATION OF ASTM A36 STEEL SUBSTRATE IN IMPROVING WEAR PROPERTIES OF PLASMA SPRAYED WC–12%Co COATING

Thermally sprayed coating is commonly used to modify the surface to improve the mechanical properties of the substrates to meet their functional requirements. Numerous research works were carried out to assess the suitability of the WC–Co coating for industrial applications using thermal spray process. Meanwhile, few researchers expressed about the deterrent effect of the decarburization on mechanical properties of the coating due to processing at high temperature in thermal spray process which reduces the efficiency of the coating process. In this research work, coating of WC–12%Co powder over ASTM A36 steel substrate through plasma spray process was considered to investigate the effect of introducing the carburization process on wear properties of the resultant coating. Carburization process was introduced on the ASTM A36 steel substrate before the application of the plasma spray coating to compensate the loss of carbon during the process. Characterization of the deposited coating was done by scanning electron microscope, X-ray diffraction, hardness, corrosive resistivity test and wear tests. The results of the tests indicated that introduction of the carburization process remarkably increased the hardness of the coating and corrosive resistivity besides improving the wear resistance.

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An Alternative Thermal Spray Process to Plasma Spray in the Aircraft and Stationary Gas Turbine Industry

Volume 5: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; General ◽

10.1115/94-gt-450 ◽

1994 ◽

Author(s):

Menno P. Zwetsloot ◽

Elliott R. Sampson

Keyword(s):

Thermal Spray ◽

Plasma Spray ◽

Nickel Aluminum ◽

Thermal Spray Process ◽

Spray Process ◽

Arc Spray ◽

Spray System ◽

Technological Advances ◽

Attachment Device ◽

Plasma Sprayed

Technological advances in arc spray have produced an arc spray system that competes very favorably with other thermal spray processes. In the past arc spray was thought of as a process for very large parts that need thick buildups. However, an attachment device has been developed which focuses the pattern and accelerates the particles and is known as the Arc Jet system. The advantages of this device were discussed by Zwetloot, Sampson and Thorpe (1993), Reference 4. This attachment device coupled with the introduction of metal cored wires that provide the same chemistries as plasma sprayed powders, provides application engineers with a viable economic alternative to existing spray methods. A comparative evaluation of a standard production plasma spray system was conducted with the arc spray process utilizing the device mentioned above. This evaluation was conducted by an airline company on four major parts coated with nickel aluminum and results show that, for those applications, the arc spray process demonstrated significant benefit. It is expected that other applications may benefit from the use of the arc spray process as well.

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Development of Corrosion Resistance Coating for AISI 410 Grade Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.813-814.135 ◽

2015 ◽

Vol 813-814 ◽

pp. 135-139 ◽

Cited By ~ 2

Author(s):

K.G. Girisha ◽

R. Rakesh ◽

C. Durga Prasad ◽

K.V. Sreenivas Rao

Keyword(s):

Corrosion Resistance ◽

Plasma Spray ◽

Corrosion Behaviour ◽

Steel Substrate ◽

Salt Spray ◽

Research Work ◽

Optical Microscope ◽

Air Plasma ◽

Spray Process ◽

Plasma Spray Process

In this present research work, corrosion behaviour of grit blasted AISI 410 steel substrate coated with NiCr/Al2O3,NiCr/ZrO2 particles was investigated using salt spray test as per ASTM B117. Coatings were prepared using air Plasma spray process. Nickel chromium was used as bond coat for obtaining good fastening between the base metal and coated particles. The microstructures of the coated and un-coated specimens were characterized using scanning electron microscope and optical microscope. Distribution coated particle was found uniform throughout the steel substrate was revealed from SEM microphotographs. The obtained results shows significant improvement in corrosion resistance and micro hardness for NiCr/Al2O3 and NiCr/ZrO2 coating deposited on steel by plasma spray process than the as sprayed base steel substrates.

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Numerical Simulation of Droplet Impact and Solidification Including Thermal Shrinkage in a Thermal Spray Process

2010 14th International Heat Transfer Conference, Volume 6 ◽

10.1115/ihtc14-22583 ◽

2010 ◽

Author(s):

Sina Alavi ◽

Mohammad Passandideh-Fard

Keyword(s):

Thermal Spray ◽

Stokes Equations ◽

Numerical Study ◽

Steel Substrate ◽

Vof Method ◽

Thermal Shrinkage ◽

Navier Stokes ◽

Molten Metals ◽

Thermal Spray Process ◽

Spray Process

In this paper, we performed a numerical study on the effects of thermal shrinkage on deposition of molten tin and nickel droplets on a steel substrate in thermal spray processes using Volume-of-Fluid (VOF) method. Thermal shrinkage is a phenomenon caused by variation of density during solidification and cooling of molten metals. In our model, the Navier-Stokes equations along with energy equation including phase change are solved using a 2-D axisymmetric mesh. We used the VOF method to track the free surface of droplet. For solidification, we used an enthalpy-porosity formulation. The simulations performed in this study are accomplished using a commercial code (Fluent). Results of these scenarios are presented: the normal impacts of 2.7mm tin droplets at 1m/s and 2m/s, initially at 240°C, onto a 27°C steel substrate. When the droplet impacts the substrate with a velocity of 1m/s, the final splat has a single cavity inside due to shrinkage. In other cases with the scales of a typical thermal spray process, the results of normal impact of nickel droplets with a velocity of 73m/s, initial temperature 1600°C and diameter 60μm to steel substrate with different temperatures are presented. In these cases shrinkage decreases the droplet splashing on the substrate.

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