This paper reports on the development of NiZn-ferrite powders and their deposition by air plasma and high-velocity oxyfuel spraying. The microstructure and phase composition of the powders and coatings are analyzed and the influence of process parameters on coating development is assessed for sprayed layers up to 500 μm thick. Particular attention is paid to the degradation of the spinel crystal structure, the formation of iron oxide phases, and elemental loss during spraying. The results show that a degree of ferrite decomposition occurs with the loss of zinc and formation of wüstite and that zinc loss is very dependent on the surface-to-volume ratio of the powder.

This article investigates composite powder materials based on double chromium and titanium carbides with nickel-chromium binder produced using self-propagating high-temperature synthesis. It focuses on the hypersonic velocity oxygen fuel coatings from the synthesized powders. Laboratory tests were focused on the solid particle erosion which occur in energy production systems such as fluidized bed combustors, advanced pulverized cool boilers, and entrained coal gasifiers. Tests were conducted at elevated temperature in a blast nozzle type of tester using bed or fly ashes retrieved from the operating CFB boilers. It was observed that, when adjusting carbide phase composition and chromium content in titanium carbide solid solution, one can control the oxidation kinetic and wear resistance of the material. Fine-grained structure and high cohesion strength of the composite materials formed during synthesis provide their excellent elevated temperature erosion performance in a wide range of test conditions.

Due to their attractive combination of properties (high resistance to oxidation and wear, high melting point, and lower density) iron and nickel aluminides show promise for the development of advanced materials and coatings However, poor room temperature ductility and susceptibility to intergranular cracking restrict their commercial application. To provide the structure required composite materials produced by the self-propagating high-temperature synthesis (SHS) are promising. In this paper, the potential of thermally sprayed NiAl/aluminum oxide and FeAl/aluminum oxide composite powders produced using the SHS method is evaluated. The results of the structure and property investigations for the synthesized powders as well as for the resulting plasma coatings are presented. Paper includes a German-language abstract.

The melting of plasma-sprayed thermal barrier coatings (TBC) using highly concentrated energy sources is one of the methods associated with increasing the density of the sprayed material and modifying the phase composition in order to improve the properties of these coatings. This paper presents the results of the investigations into TBC melting using pulse and continuous carbon dioxide lasers. Paper includes a German-language abstract.

This work evaluates the potential of using new competitive powders of Fe/TiC system for plasma spraying of wear resistant coatings. To improve coating properties, Cr and Ni were added to the iron matrix. The results of complex investigations of plasma coatings from such materials are presented.

The poblems of metal-titanium carbide coatings processing by air, low pressure and underwater plasma as well as high velocity oxygen fuel spraying are under consideration. Among the different methods of metal-TiC powders production, like mixing of carbides with scale structure metals, agglomeration with binders, a matter of special interest is the high temperature synthesis of TiC in presence of metallic alloy. The characteristic features of these materials include the carbide phases forming, their bonding with the alloy and reactions during spraying, grain size and their distribution, alloy behavior during synthesis and spraying. Finally, the abrasive wear and erosion resistance of Al-Si/TiC, Fe-Cr/TiC and Ni-Cr/TiC coatings is analyzed.