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It has recently been found that the anodizing of FeAl alloys allows the formation of iron-aluminum oxide layers with interesting semiconducting properties. However, the lack of systematic research on different anodizing regimes is hampering their full exploitation in numerous photoelectrochemical-related applications. This study address, for the first time, the systematic effect of the electrolyte composition on the formation of self-ordered oxide films by anodizing on cast Fe3Al alloy. The Fe3Al alloy was anodized in 3 electrolytes with different water-ethylene glycol (EG) ratios (pure water, 25 vol.%-EG, and 50 vol.%-EG solutions) at a constant tartaric-sulfuric acids concentration, different voltages (10–20 V) and treatment times (2–60 min). After anodizing, all anodic oxide layers were annealed at 900 °C to form semiconductive iron-aluminum crystalline phases. Conventional techniques were used to systematically ascertain the morphological (SEM/EDS, XRD, eddy-current measurements) and semiconductive (UV–VIS reflectance spectroscopy) properties of these oxide layers. The results confirmed the formation of homogeneous and self-ordered anodic oxide layers at 10 and 15 V, regardless of the electrolyte composition. Namely, anodic films formed in electrolytes containing EG showed lower pore sizes, growth rates, and film thicknesses than those anodic films formed in the aqueous-based electrolyte. The annealing post-treatment results in different Fe-Al oxides (FexOy, FeAl2O4, etc.) with superior band gap values than those for non-annealed films. [ABSTRACT FROM AUTHOR]

The fatigue response and high-temperature corrosion resistance of Inconel 740 nickel alloy in its as-received state, and the same material with aluminized surface layer, were investigated. The aluminized layer was applied by using the chemical vapor deposition process with the participation of AlCl3 vapors under a hydrogen protective atmosphere at a temperature of 1040°C for 8 h and internal pressure of 150 hPa. The microstructure of the aluminized layer was characterized through scanning electron microscopy and x-ray energy dispersive spectroscopy analysis. It was found that Inconel 740 with an aluminized surface exhibited an improved hardness and fatigue response of 100 MPa in the whole range of stress amplitudes from 350 MPa to 650 MPa. Additionally, the application of the aluminization process enhanced service life as well as the corrosion resistance of the alloy in question and effectively protected it against high-temperature corrosion. [ABSTRACT FROM AUTHOR]

This study presents the effect of the thermo-oxidative ageing conditions on the properties of polyoxymethylene copolymer (POM-C), acrylonitrile–butadiene–styrene (ABS), and polycarbonate (PC). For this purpose, the process of accelerated aging of these materials was carried out for a period of 21 to 56 days at an elevated temperature of 140 °C. Then, the effect of this process on the thermal properties of these materials was determined using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Special attention was paid to the change in glass transition temperature. To determine the change in mechanical properties, a standard tensile test was performed. Additionally, the microstructure of the materials studied was analysed using a scanning electron microscope. Research carried out using DMA, DSC and tensile tests at different temperatures showed that generally in the case of POM-C there is no change in the material properties, however, a slight improvement can be noted. In the case of ABS, during the first 21 days of aging, there were large changes in all the material properties studied. For polycarbonate, the DMA analysis showed that there is no change in the glass transition temperature of both aged and unaged samples. [ABSTRACT FROM AUTHOR]