Author: A Rüdiger, U Koster
Institute: Department of Chemical Engineering, University of Dortmund, D-44221 Dortmund, Germany
The corrosion behavior of Al-Cu-Fe quasicrystals is a unique area of study that attracts the attention of researchers and engineers. Quasicrystals, with their unusual symmetry and periodicity, exhibit unique mechanical and chemical properties, making them promising for use in a variety of applications, including antifriction coatings and catalytic converters.
Research shows that the corrosion resistance of Al-Cu-Fe quasicrystals significantly exceeds that of traditional metals due to their complex architecture and the presence of protective oxide films. These films prevent further interaction with the external environment, but their stability and composition may vary depending on operating conditions.
Particular attention should be paid to phenomena occurring at the phase boundary, where quasicrystals can exhibit different behavior when in contact with aggressive environments. Optimization of the composition and conditions of synthesis of quasicrystals opens up new horizons for increasing their corrosion resistance and expanding their functionality in engineering applications.
Corrosion resistance is a critical issue. That is why the corrosion study of quasicrystalline and related crystalline phases in the Al-Cu-Fe system was carried out at medium pH values to better understand the influence of the quasicrystalline structure. Salt spray tests were carried out at 35°C using different single-phase materials of this system. The highest corrosion resistance was shown by crystalline AlFe aluminates and frying pans, turbine blades, and extruders. When quasicrystalline coatings such as Fe2 were applied to form a protective oxide layer, it was noted that quasicrystalline alloys and crystalline Al7Cu2Fe were subject to intense corrosion, leading to the formation of Cu, Cu2O, and Al(OH)3. The process of anodic polarization of icosahedral quasicrystals Al63Cu25Fe12 in 0.1 N NaOH solution confirms the formation of an oxide layer of FeO and Cu2O, with minor signs of phase transition arising from the release of Al as a result of corrosion. The thickness of the oxide layer depends on the scanning time, but not on the period of further polarization.
Analysis of the corrosion behavior of Al-Cu-Fe quasicrystals shows that their high corrosion resistance is due not only to protective oxide films, but also to their unique internal structure. These materials have complex multiple symmetries, which leads to the formation of clearly organized layers capable of effectively blocking the diffusion of corrosive agents. Thus, even under extreme conditions, quasicrystals demonstrate lower susceptibility to corrosion compared to conventional metal alloys.
Another important aspect is the influence of temperature and environment on corrosion processes. Some studies show that at elevated temperatures or in aggressive chemical environments such as salt solutions, quasi-crystals can exhibit unexpected corrosion reactions. This opens up new perspectives for the development of quasi-crystalline coatings adapted to specific operating conditions, for example in the marine or chemical industries.
The potential for using Al-Cu-Fe quasicrystals in antifriction coatings and catalytic converters also requires further study. Successful research results can lead to the creation of new materials with improved functional characteristics, which, in turn, will open up opportunities for innovative technological solutions in various industries.