Crack Growth Tests in Air Plasma-Sprayed Yttria Coatings for Alumina Ceramic Matrix Composites

Microstructure formation in plasma-sprayed functionally graded NiCoCrAlY/yttria-stabilized zirconia coatings

Functionally graded NiCoCrAlY/yttria-stabilized zirconia coatings were fabricated by plasma spraying using mechanically alloyed, plasma-spheroidized NiCoCrAlY/yttria-stabilized zirconia (YSZ) composite powders. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) analysis revealed that oxidation of aluminum, chromium and yttrium in the NiCoCrAlY alloy occurred in th...

Calibration of Raman spectroscopy in the stress measurement of air-plasma-sprayed yttria-stabilized zirconia.

Thermal barrier coatings (TBC) are used widely on a range of components that operate at high temperatures. We report measurement of the factor that is required to convert the Raman shift to stress for air plasma sprayed yttria (7 wt %) stabilized tetragonal zirconia (ZrO(2)) (YSZ) thermal barrier coatings. The factor is evaluated for the as-coated condition and also following a heat treatment a...

Bond Strength of Plasma Sprayed Ceramic Coatings on the Phosphated Steels

P. Pokorny, L. Mastny, V. Sykora, Institute of Chemical Technology Prague, Czech Republic Z. Pala, V. Brozek, Institute of Plasma Physics ASCR v.v.i. Prague, Czech Republic In the presented work, results of adhesion measurements for different systems of steel sheet-phosphate interlayerceramic coating are described. The interlayers were produced by zinc phosphating; alumina, olivine and zirconia...

Microstructure and Microwave Absorption Properties of Flame Sprayed Ceramic Coatings

In this research work, airplane grade aluminum alloy substrate was coated by Al2O3/ TiO2 ceramic coatings in two different compositions as 50:50 and 87:13 using Flame spraying technique. The surface & cross-sectional morphological characterizations of the Al2O3/ TiO2 powders and coatings were performed by scanning electron microscopy (SEM). The microwave absorbing properties of coatings were ex...

Reactions between the Phases in Glass-alumina Ceramic Composites