Corrosion behavior of single- and poly-crystalline dual-phase TiAl-Ti3Al alloy in NaCl solution

• Published in: International journal of minerals, metallurgy and materials Vol. 30; no. 4; pp. 689 - 696
• Main Authors: Wang, Dongpeng, Chen, Guang, Wang, Anding, Wang, Yuxin, Qiao, Yanxin, Liu, Zhenguang, Qi, Zhixiang, Liu, Chain Tsuan
• Format: Journal Article
• Language: English
• Published: Beijing University of Science and Technology Beijing 01.04.2023; Springer Nature B.V; Centre for Advanced Structural Materials,Department of Mechanical and Biomechanical Engineering,City University of Hong Kong,Hong Kong 999077,China%Engineering Research Center of Materials Behavior and Design,Ministry of Education,Nanjing University of Science and Technology,Nanjing 210094,China%Centre for Advanced Structural Materials,Department of Mechanical and Biomechanical Engineering,City University of Hong Kong,Hong Kong 999077,China; School of Materials Science and Engineering,Dongguan University of Technology,Dongguan 523808,China%School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212100,China%Centre for Advanced Structural Materials,Department of Mechanical and Biomechanical Engineering,City University of Hong Kong,Hong Kong 999077,China; School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212100,China
• Subjects: Ceramics; Characterization and Evaluation of Materials; Charge transfer; Chemistry and Materials Science; Composites; Composition; Corrosion; Corrosion and Coatings; Corrosion potential; Corrosion rate; Corrosion resistance; Crystals; Electrochemical analysis; Electrochemical impedance spectroscopy; Electrochemistry; Electrode polarization; Engineering; Glass; High strength alloys; Impedance; Intermetallic compounds; Materials Science; Mechanical properties; Metallic Materials; Morphology; Natural Materials; Pitting (corrosion); Pitting potential; Polycrystals; Scanning electron microscopy; Single crystals; Sodium chloride; Software; Spectrum analysis; Surface properties; Surfaces and Interfaces; Thin Films; Titanium alloys; Titanium aluminides; Titanium base alloys; Tribology; Yield stress; titanium alloy; corrosion; X-ray photoelectron spectroscopy; single crystal
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-022-2513-5

To clarify the correlation of single-crystalline structure with corrosion performance in high-strength TiAl alloys, electrochemical and surface characterization was performed by comparing Ti-45Al-8Nb dual-phase single crystals with their polycrystalline counterparts in NaCl solution. Polarization curves show a lower corrosion rate and a higher pitting potential of ∼280 mV for the dual-phase single crystals. Electrochemical impedance spectroscopy and potentiostatic polarization plots revealed a higher impedance of the charge transfer through the compact passive film. Surface composition analysis indicated a compact film with more content of Nb, as twice as that in the film on the polycrystals. Our results reflect that the dual-phase Ti-45Al-8Nb single crystals possess a higher corrosion resistance in NaCl solution, compared with their polycrystalline counterpart, arising from a more homogeneous microstructure and composition distribution.