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Composite coatings, consisting of a ceramic barium hexaferrite and polyester, were manufactured byatmospheric plasma spraying. The crystalline structure of the barium hexaferrite was preserved duringthe spraying process while the polyester first (partly) melted and then resolidified. The high magneticlosses of the barium hexaferrite at mm-waves were coupled to the dielectric losses of the polyester in thecomposite coating and the superior electromagnetic absorption of the composite coating with respect tothe pure materials was determine

Thick coatings of CoTi-substituted Ba hexaferrite with the\ud nominal composition BaCoTiFe10O19 were prepared using atmospheric\ud plasma-spraying technology. The coatings were prepared\ud from prereacted powders of the desired composition. The\ud as-deposited coatings showed a high degree of crystallinity. A\ud detailed investigation of the coatings’ phase compositions was\ud conducted with micro-Raman spectroscopy and energy-dispersive\ud X-ray spectroscopy. Two magnetic ferrite phases, CoTisubstituted\ud Ba hexaferrite and Co ferrite, were identified in the\ud coatings. An X-ray powder-diffraction analysis and a quantitative\ud structural analysis based on Rietveld refinement showed that\ud the mass ratio of the two phases and their chemical composition\ud varied with respect to the spraying parameters. Consequently,\ud the static and microwave magnetic properties of the as-sprayed\ud coatings also varied. We were able to explain the formation\ud of the two ferrite phases based on the interplay between the\ud p..