Relationship between the fatigue behavior and grain structures of an as-extruded Mg-6.2%Zn-0.6%Zr (in wt.%) alloy. (20th June 2023)

• Record Type: Journal Article
• Authors: Wang, B.J.; Xu, D.K.; Jiang, C.L.; Sheng, L.Y.; Han, E.H.
• Is Part Of: Journal of materials science & technology. Volume 149(2023)
• Page Start: 119
• Page End: 126
• Publication Date: 2023-06-20
• Subjects: Mg alloys -- Grain structure -- Cyclic slips -- Fatigue behavior -- Crack initiation; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2022.10.087
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: The tension-tension fatigue behavior of an as-extruded ZK60 alloy is sensitive to the grain structure. The "bi-modal" grain structure has the lowest fatigue strength. Fatigue cracks in fine grain structure nucleate at the grain boundaries. Fatigue crack initiation of "bi-modal" and coarse grain structures is along slip bands. Abstract: Through investigating the tension-tension fatigue behavior of an as-extruded Mg-6.2 wt.%Zn-0.6 wt.%Zr (ZK60) alloy, it revealed that the determined fatigue strength at 10 7 cycles was quite sensitive to the grain structure. Among them, the fine grain structure had the highest fatigue strength of 130 MPa, whereas the typical "bi-modal" grain structure had the lowest fatigue strength of 110 MPa. Failure analysis demonstrated that for the fine grain structure, fatigue cracks preferentially nucleated at grain boundaries. For the "bi-modal" and coarse grain structures, the fatigue crack initiation was dominated by the cracking along slip bands. Graphical abstract: Image, graphical abstract