Analysis of thermodynamic parameters for designing quasicrystalline Al-Ni-Fe alloys with enhanced corrosion resistance

• Published in: Journal of alloys and compounds 2021-07, Vol.868, p.159241, Article 159241
• Main Authors: Babilas, Rafał, Młynarek, Katarzyna, Łoński, Wojciech, Lis, Mateusz, Łukowiec, Dariusz, Kądziołka-Gaweł, Mariola, Warski, Tymon, Radoń, Adrian
• Format: Article
• Language: English
• Subjects: Al-based alloys; Alloys; Aluminum; Corrosion rate; Corrosion resistance; Corrosion resistant alloys; Crystal structure; Crystallinity; Crystallization; Differential thermal analysis; Electrochemical measurements; Enthalpy; Ferrous alloys; Gibbs free energy; Iron; Iron 57; Mossbauer spectroscopy; Mössbauer spectroscopy; Nickel base alloys; Optimization; Parameter identification; Quasicrystals; Solid solutions; Thermodynamics; X-ray diffraction
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.159241

In this work, the compositions of Al-Ni-Fe alloys were determined based on thermodynamic parameters optimization. Decagonal quasicrystalline phase D-Al70.83Fe9.83Ni19.34 was identified in the alloy with the highest Gibbs free energy of solid solution formation, i.e., Al71Ni24Fe5. According to this, the configurational entropy and enthalpy of solid solution formation must reach equilibrium to form quasicrystals in Al-Ni-Fe alloys. Differential thermal analysis and X-ray diffraction were used to describe the crystallization mechanism as a function of Fe concentration. 57Fe Mössbauer spectroscopy was used to describe the Fe local environment in crystalline alloys and quasicrystals. Moreover, the influence of quasicrystalline phases on improving the corrosion resistance was investigated. Quasicrystalline Al71Ni24Fe5 alloy had a six-times lower corrosion rate than its crystalline counterparts. Although this alloy showed the best corrosion resistance, all high-pressure cast Al-Fe-Ni alloys displayed improved corrosion resistance. •Thermodynamic approach can be used to obtain Al-Ni-Fe alloys with modulated structure.•Gibbs free energy of solid solution formation optimization allowed to obtain quasicrystals.•The configuration entropy between 5.67 and 6.47 J/mol·K promotes quasicrystals formation.•Structure fragmentation under high cooling rate results in corrosion resistance increase.•Precipitation of quasicrystals is responsible for low corrosion rate (0.005 ± 0.01 mm/year).