Investigation of nanostructured and conventional alumina–titania coatings prepared by air plasma spray process

Thermal barrier coatings (TBC) with the metallic NiCrAlY bond coat are often used in many aircraft engines to protect superalloy components from high-temperature corrosion thereby to improve the life of gas turbine components. The search for new TBC material has been intensified in recent years due to lack of thermo-physical properties of conventionally used Yttria stabilized Zirconia (YSZ) TBCs. Recently, the rare earth containing Samarium Strontium Aluminate (SSA) based ceramic was proposed as a new TBC material due to its matching thermo-physical properties with the substrate. The present work focused on the synthesis of SSA ceramics for TBCs application and its coatings development on Ni-based superalloy Inconel 718 substrate by air plasma spray process. The X-ray photoelectron spectroscopy (XPS) result confirmed the formation of single phase SSA ceramic after synthesis. The surface morphology of SSA TBCs is mainly composed of melted splats, semi and un-melted particles. The cross-sectional SEM micrographs did not show any spallation at the interface which indicated good mechanical interlocking between the bond coat and ceramic top coat. The Young’s modulus and hardness of SSA TBCs were found to be 80 and 6.1 GPa, respectively. The load-depth curve of SSA TBC showed good elastic recovery about 47 %.

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Effect of heat treatment in air on bonding strength and micro-structure of Al2O3-13 wt % TiO2/NiCrAl coating prepared by air plasma-spray process

Protection of Metals and Physical Chemistry of Surfaces ◽

10.1134/s2070205116060228 ◽

2016 ◽

Vol 52 (6) ◽

pp. 1064-1069 ◽

Cited By ~ 2

Author(s):

Guowei Wang ◽

Zehua Zhou ◽

Zehua Wang ◽

Jia Shao ◽

Han Liu ◽

...

Keyword(s):

Heat Treatment ◽

Plasma Spray ◽

Bonding Strength ◽

Air Plasma Spray ◽

Air Plasma ◽

Micro Structure ◽

Spray Process ◽

Plasma Spray Process

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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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