Microstructural Characteristics, Mechanical and Corrosion Properties of an Extruded Low-Alloyed Mg-Bi-Al-Zn Alloy

Abstract

An extruded low-alloyed Mg-Bi-Al-Zn alloy combining excellent tensile properties (YS = 201 MPa, EL = 29. 4%) with high corrosion resistance (Pi = 0.14 mm/a) for biomedical application is successfully developed in this study. The extruded alloy is mainly composed of dynamic recrystallized (DRXed) grains (2.32 ± 0.12 μm) and strongly textured coarse non-DRXed grains, as well as certain nano-scaled Mg3Bi2 precipitates (135.68 ± 27.86 nm). Note that most basal planes for non-DRXed grains are preferentially distributed parallel to the extrusion direction. The study explored the dependences of the properties and relevant mechanisms of the studied alloy on its microstructural characteristics in terms of grain size, grain orientation, and precipitates.