The powders of Bi2O3 and Bi2WO6 were prepared by calcination, sintering and crushing. Their sizes were screened out to be in the range from 50 to 150 µm. The initial spray parameters were optimised using numerical codes simulating the behaviour of powders in plasma jet. Spray experiments onto metallic substrates were carried out using commercial plasma torch SG-100, equipped in an external powder injector. The spraying of coatings was carried out by varying electric power input to plasma, distance of spraying and the geometry of injector. The morphology of sprayed coatings was investigated using scanning electron microscope (SEM). X-ray Diffraction (XRD) of Bi2O3 coatings revealed the α-Bi2O3 phase, present in the initial powder, and also β-Bi2O3 in some of the samples. Reduction of oxide into metallic Bi at spraying process was not discovered using XRD and Differential Thermal Analysis (DTA). Bi2WO6 powder was crystallized in an orthorhombic phase that transformed into tetragonal one at spraying. Finally, the X-ray Photoelectric Spectroscopy (XPS) investigations revealed a possible presence of Bi(OH)3 phase in the coatings sprayed using Bi2O3 powder.

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