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Thermal barrier coatings (TBCs) are widely used for protection of gas turbine parts from high temperature and corrosion. In the present study, the new concept of TBCs with three-element-modified aluminide coatings was presented. In the first stage, the Pt and Pd were electroplated on MAR M247 nickel superalloy. In the next stage, the low-activity CVD aluminizing process with Zr or Hf doping was conducted. The ceramic layer containing yttria-stabilized zirconia was obtained by the plasma spray physical vapour deposition (PS-PVD) method. The microscopic examination showed the formation of aluminide coating containing up to 5 at% of Pt and 10 at% of Pd in (Ni, Pt, Pd)Al solid solution. The small concentration of Hf and Zr in diffusion zone of aluminide bond coat was noted as well. The outer ceramic layer was characterized by columnar structure typically formed during the PS-PVD process. The obtained results showed that the new concept of TBCs formed using new processes might be an attractive alternative to conventional coatings produced using the expensive electron beam physical vapour deposition (EB-PVD) method.

New refining technology of soda-calcium-silicon glass surfaces with inorganic compounds nano-molecules has been presented in the study. In order to determine modification of the glass surface SEM observation and EDX analysis have been carried out. The UV-VIS, photo-elasticity and ellipsometry examinations were carried out on glass samples. The results of investigations that have been conducted show that refining process of the glass surface by use of nanopowder inorganic compounds deposited electrostatically on glass surface provides forming of very thin (about 50 nm) surface layers [1]. This method of surface modification improves physical and chemical glass properties. In this paper results of microhardness test of refined glass were also presented.

Ytterbium zirconate (Yb2Zr2O7) is one of the most promising materials for yttria-stabilized zirconia (YSZ) replacement as a thermal barrier coating (TBCs) application. In the presented report, the experimental synthesis of Yb2Zr2O7 coating using novel Reactive Plasma Spray Physical Vapor Deposition (Reactive PS-PVD) is described. The obtained coating, irrespective of the power current (1800, 2000 and 2200 A), was characterized by a hybrid structure and a thickness of about 80–110 μm. The results of XRD phase analysis showed the formation of ytterbium zirconate in the coating but the presence of ytterbium and zirconium oxides was also detected. The oxides were not observed in calcinated powder. The decrease in thermal conductivity with power current increase was observed. It was the result of higher thickness and better columnar structure of the coating obtained using higher power current of the plasma torch. [ABSTRACT FROM AUTHOR]

Ceramic topcoats of thermal barrier coatings (TBCs) make it possible to increase the working temperature of the hot sections of jet engines. Yttria-stabilized zirconia oxide (YSZ) is usually used to protect the turbine blades and vanes against high temperature and oxidation. It is necessary to develop new materials which can operate at higher temperatures in a highly oxidizing gas atmosphere. Re2Zr2O7-type pyrochlores are promising YSZ replacements. Usually, they are produced by mixing pure oxides in the calcination process at higher temperatures. In a recent article, the new concept of pyrochlore synthesis during the deposition process was presented. The new technology, called reactive plasma spray physical vapor deposition (reactive PS-PVD), was developed and a Gd2Zr2O7 (GZO) coating was achieved. The reactive PS-PVD process allowed for the use of a mixture of untreated ZrO2 and Gd2O3 powders as reactants, instead of the commercially available gadolinium zirconate powders used in other types of processes. The results of microstructure observations revealed a columnar microstructure in the produced ceramic layer. The phase composition indicated the presence of gadolinium zirconate. Thermal analysis showed a decrease in the thermal conductivity in the range of 700 to 1200 °C of the produced layers, as compared to the layer made of the currently used conventional YSZ. [ABSTRACT FROM AUTHOR]