Microstructural characterization of plasma sprayed Al2O3-40wt.% TiO2 coatings on high density graphite with different post-treatments

III-V nitrides grown on (0001) sapphire substrates often contain a very high density of defects; this high density is usually attributed to the poor lattice and thermal match between the nitride and the sapphire [1]. There is thus a need to understand the defect structures in these materials. In the present study, a microstructural characterization of MBE-grown GaN films on (0001) sapphire using various TEM techniques was performed to evaluate defect structures in this material. This paper will outline some of the different types of defects found in these films and suggest some possible mechanisms by which they were formed.

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Thermophysical, mechanical and microstructural characterization of aged free-standing plasma-sprayed zirconia coatings

Acta Materialia ◽

10.1016/j.actamat.2008.04.067 ◽

2008 ◽

Vol 56 (16) ◽

pp. 4477-4488 ◽

Cited By ~ 66

Author(s):

F. Cernuschi ◽

P.G. Bison ◽

S. Marinetti ◽

P. Scardi

Keyword(s):

Microstructural Characterization ◽

Free Standing ◽

Plasma Sprayed

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Microstructural characterization of plasma sprayed Ln 2 Zr 2 O 7 thermal barrier coatings by electron microscopy methods

Microscopy Research and Technique ◽

10.1002/jemt.23441 ◽

2020 ◽

Vol 83 (5) ◽

pp. 523-530

Author(s):

Grzegorz Moskal

Keyword(s):

Electron Microscopy ◽

Thermal Barrier Coatings ◽

Microstructural Characterization ◽

Thermal Barrier ◽

Barrier Coatings ◽

Plasma Sprayed

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Thermal-Cycling Behavior of Plasma-Sprayed Partially Stabilized Zirconia Coatings on High-Density Graphite Substrate

Journal of Thermal Spray Technology ◽

10.1007/s11666-015-0268-5 ◽

2015 ◽

Vol 24 (6) ◽

pp. 925-937 ◽

Cited By ~ 3

Author(s):

Jagadeesh Sure ◽

K. Thyagarajan ◽

C. Mallika ◽

U. Kamachi Mudali

Keyword(s):

Thermal Cycling ◽

High Density ◽

Graphite Substrate ◽

Stabilized Zirconia ◽

Partially Stabilized Zirconia ◽

Density Graphite ◽

Plasma Sprayed ◽

Thermal Cycling Behavior ◽

Cycling Behavior

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Preparation and Characterization of Plasma-Sprayed and Laser-Remelted Ni60/Ni-WC Coatings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.540.17 ◽

2014 ◽

Vol 540 ◽

pp. 17-20

Author(s):

Dong Sheng Wang

Keyword(s):

Laser Power ◽

Composite Coatings ◽

Microstructural Characterization ◽

Matrix Alloy ◽

Laser Remelting ◽

Base Matrix ◽

High Microhardness ◽

Sprayed Coating ◽

Plasma Sprayed

In this study, Ni60/Ni-WC composite coatings were first prepared by plasma spraying. Then, the coatings were remelted successively with a CO2 laser. The influences of laser power on the microstructural characterization and microhardness of the coatings were investigated. The results show that the defects of as-sprayed coating like lamellar stacking microstructure and pores were eliminated by laser remelting, and the remelted coating possessed a denser microstructure. With the increase of the laser power, the burning loss and dissolve of the WC particles is increased, while the dilution rate of the coating becomes large. The laser-remelted samples had higher hardness than the as-sprayed one. Laser power has a great impact on the coating and an optimized process parameter is helpful to achieve appropriate melting of WC particles, which leads to retain a high proportion of hard phase in the coating, good combination between the WC particles and Ni-base matrix alloy, and high microhardness.

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