The tensile properties and high cyclic fatigue characteristics of Mg–5Li–3Al–1.5Zn-2RE alloy

✍ Scribed by Tingqu Li; Yongbing Liu; Zhanyi Cao; Dongmei Jiang; Liren Cheng

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 892 KB
• Volume: 527
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2010.08.094

✦ Synopsis

The tensile and fatigue properties of the Mg-5Li-3Al-1.5Zn-2RE (LAZ531-2RE) alloy were presented. The alloy was prepared by hot extrusion after vacuum casting. The Portevin-Le Chatelier (PLC) phenomenon was observed during tensile deformation. The PLC effect was attributed to the dynamic interaction between solute atoms (Li) and dislocation movement. The abnormal negative strain rate sensitivity (SRS) in high strain rate regime can be explained by the dynamic strain ageing (DSA) mechanism. The higher ductility may be associated with finer-grained microstructure and Li addition. Fatigue crack propagation was characterized by striation-like features. The smaller spacing of fatigue striations and larger fatigue crack propagation zone at the lower total strain amplitude gave rise to a longer fatigue life.