Corrosion behavior characterization of as extruded Mg-8Li-3Al alloy with minor alloying elements (Gd, Sn and Cu) by scanning Kelvin probe force microscopy. (November 2020)

• Record Type: Journal Article
• Authors: Hu, Zhi; Yin, Zheng; Yin, Zhou; Wang, Kun; Liu, Qidong; Sun, Pengfei; Yan, Hong; Song, Honggun; Luo, Chao; Guan, Hongyu; Luc, Chassagne
• Is Part Of: Corrosion science. Volume 176(2020)
• Publication Date: 2020-11
• Subjects: Mg–Li alloys -- corrosion resistance -- Gd -- Sn -- Cu -- SKPFM; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2020.108923
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: The surface potential of the secondary phases was characterized by SKPFM. The less noble Al2 Gd phase improved corrosion resistance of as extruded LA83 alloys. The secondary cathode (Mg2 Sn) shows weakly effects on the micro-galvanic corrosion. Uniform corrosion was formed in the surface of the LA83-Gd and LA83-Sn alloys. Local serious corrosion was induced by the nobler AlCuMg phase (∼720 mV). Abstract: The effects of Gd, Sn and Cu on the corrosion behavior of as extruded Mg–8Li–3Al (LA83) alloy were characterized by scanning Kelvin probe force microscopy, weight loss, hydrogen evolution, and electrochemical measurements. Result revealed that many Al2 Gd, Mg2 Sn, and AlCuMg particles were discovered in modified alloys, respectively. The combined experimental results of weight loss, hydrogen evolution, and electrochemical analysis indicated that the addition of Gd and Sn improve the corrosion resistance of as extruded LA83 alloy while the addition of Cu weaken its corrosion resistance. The corrosion mechanisms of different elements in as extruded samples were discussed.