Institute of plasma physics › Structure of IPP › Plasma Chemistry and Materials Division › Materials Engineering Department › Gallery › 01-vyzkum
Coatings
Garnet coating - top view
Garnet coating - top view
Top view of a coating surface shows the flattened and solidified droplets and a crack caused by tensile quenching stress, originating from the large temperature drop. Photo by Blahoslav Kolman.
Garnet coating - top view
Top view of a coating surface shows the flattened and solidified droplets and a crack caused by tensile quenching stress, originating from the large temperature drop. Photo by Blahoslav Kolman.
Solidification texture on a splat surface
Dendrites protruding from an alumina splat surface. Photo by Blahoslav Kolman.
Dendrites protruding from an alumina splat surface. Photo by Blahoslav Kolman.
Resolidified particle on top of a coating after ion beam processing
Ion beam processed Al2O3 coating
Surface of an Al2O3 coating treated with Ar ion beams. Round particle on top of the coating was not completely melted; its bottom half exhibits a dendritic structure. Its top half has been melted by the ion beam and shows that only a thin surface layer was affected.
Part of the "Surface Modification of Materials by High Energy Ion Beams" project. Photo by Jiří Matějíček, 2000.
Ion beam processed Al2O3 coating
Surface of an Al2O3 coating treated with Ar ion beams. Round particle on top of the coating was not completely melted; its bottom half exhibits a dendritic structure. Its top half has been melted by the ion beam and shows that only a thin surface layer was affected.
Part of the "Surface Modification of Materials by High Energy Ion Beams" project. Photo by Jiří Matějíček, 2000.
Impression of a resolidified particle in a coating
Impression of a resolidified particle in an alumina coating
A particle that had resolidified during the flight and was embedded in the coating as a spherical inclusion, to be pulled out during a fracture. The fracture surface shows conformation of the subsequently arriving splats to the spherical shape and the solidification texture on its surface (indicating an intimate contact). Photo by Jiří Matějíček, 2001.
Impression of a resolidified particle in an alumina coating
A particle that had resolidified during the flight and was embedded in the coating as a spherical inclusion, to be pulled out during a fracture. The fracture surface shows conformation of the subsequently arriving splats to the spherical shape and the solidification texture on its surface (indicating an intimate contact). Photo by Jiří Matějíček, 2001.
Fracture surface of an alumina coating
Fracture surface reveals typical structure of a plasma sprayed coating: lamellae created by flattening of molten particles upon impact, thin flat voids between them in regions of imperfect contact, columnar grain structure in each lamella caused by directional heat removal during rapid solidification. Photo by Blahoslav Kolman.
Fracture surface reveals typical structure of a plasma sprayed coating: lamellae created by flattening of molten particles upon impact, thin flat voids between them in regions of imperfect contact, columnar grain structure in each lamella caused by directional heat removal during rapid solidification. Photo by Blahoslav Kolman.
Cross-section of a zirconia coating
Polished cross-section of plasma sprayed zirconia coating shows three major void systems: volumetric pores, horizontal (interlamellar) voids and vertical (intralamellar) cracks. Photo by Blahoslav Kolman.
Polished cross-section of plasma sprayed zirconia coating shows three major void systems: volumetric pores, horizontal (interlamellar) voids and vertical (intralamellar) cracks. Photo by Blahoslav Kolman.
Examples of different splat surfaces in an alumina coating
Examples of different splat surfaces in Al2O3 + 13%TiO2 coating
Photo by Blahoslav Kolman.
Examples of different splat surfaces in Al2O3 + 13%TiO2 coating
Photo by Blahoslav Kolman.
MgCaTiO3 coatings - as-sprayed and annealed structure
MCT coatings
MCT (MgTiO3+CaTiO3) coatings - cross-sections (top - as-sprayed, bottom - annealed at 1250 C on air for 2 hours). In the as-sprayed coating, an excellent splat cohesion can be observed, with well bonded lamellae and only vertical cracks. Different shades correspond to different impurity content. The annealed coatings shows overall homogenization, clustering of the Zr-rich zones and the voids. Different annealing temperatures led to different void morphology, but did not affect the morphology of the Zr-rich zones. Part of the "Plasma Spraying of Titanates" project. Photo by Blahoslav Kolman.
MCT coatings
MCT (MgTiO3+CaTiO3) coatings - cross-sections (top - as-sprayed, bottom - annealed at 1250 C on air for 2 hours). In the as-sprayed coating, an excellent splat cohesion can be observed, with well bonded lamellae and only vertical cracks. Different shades correspond to different impurity content. The annealed coatings shows overall homogenization, clustering of the Zr-rich zones and the voids. Different annealing temperatures led to different void morphology, but did not affect the morphology of the Zr-rich zones. Part of the "Plasma Spraying of Titanates" project. Photo by Blahoslav Kolman.
MgCaTiO3 coatings - as-sprayed and annealed structure
MCT coatings
MCT (MgTiO3+CaTiO3) coatings - cross-sections (top - as-sprayed, bottom - annealed at 1250 C on air for 2 hours). In the as-sprayed coating, an excellent splat cohesion can be observed, with well bonded lamellae and only vertical cracks. Different shades correspond to different impurity content. The annealed coatings shows overall homogenization, clustering of the Zr-rich zones and the voids. Different annealing temperatures led to different void morphology, but did not affect the morphology of the Zr-rich zones. Part of the "Plasma Spraying of Titanates" project. Photo by Blahoslav Kolman.
MCT coatings
MCT (MgTiO3+CaTiO3) coatings - cross-sections (top - as-sprayed, bottom - annealed at 1250 C on air for 2 hours). In the as-sprayed coating, an excellent splat cohesion can be observed, with well bonded lamellae and only vertical cracks. Different shades correspond to different impurity content. The annealed coatings shows overall homogenization, clustering of the Zr-rich zones and the voids. Different annealing temperatures led to different void morphology, but did not affect the morphology of the Zr-rich zones. Part of the "Plasma Spraying of Titanates" project. Photo by Blahoslav Kolman.
Alumina+zircon composite coating
Composite coating made from 50% alumina (dark phase) and 50% zircon (light phase) annealed at 1300 C. Photo by Blahoslav Kolman.
Composite coating made from 50% alumina (dark phase) and 50% zircon (light phase) annealed at 1300 C. Photo by Blahoslav Kolman.
Cracks in a thick alumina deposit
Cracks in a thick gray alumina deposit
Fracture surface of a non-typical thick deposit from gray alumina reveals horizontal macroscopic cracks. These originate from imperfect bonding between deposit layers when the underlying deposit cooled down between subsequent passes of the spraying torch. Photo by Blahoslav Kolman.
Cracks in a thick gray alumina deposit
Fracture surface of a non-typical thick deposit from gray alumina reveals horizontal macroscopic cracks. These originate from imperfect bonding between deposit layers when the underlying deposit cooled down between subsequent passes of the spraying torch. Photo by Blahoslav Kolman.
