A comparison of microstructure and mechanical properties of Mg–9Al–1Zn sheets rolled from as-cast, cast-rolling and as-extruded alloys

• Published in: Materials & design 2016-01, Vol.89, p.167-172
• Main Authors: Wang, Hui–Yuan, Zhang, En–Bo, Nan, Xiao–Long, Zhang, Lei, Guan, Zhi–Ping, Jiang, Qi–Chuan
• Format: Article
• Language: English
• Subjects: Alloys; Extrusion; Grain refinement; Magnesium alloys; Magnesium base alloys; Mechanical properties; Microstructure; Preprocessing; Rolling; Superplasticity; Surface layer; Texture
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2015.09.107

The effects of different initial microstructures of Mg–9Al–1Zn alloy on microstructure and mechanical properties after rolled were investigated in this study. Three original Mg–9Al–1Zn alloys involving as-cast, cast-rolling and as-extruded conditions present different initial grain sizes and initial textures. After a rolling process, all the corresponding rolled sheets show a fine-grained recrystallized microstructure (2.7–3.6μm) and a strong basal (0002) texture. The tensile tests of the three rolled sheets show that the as-extruded alloy after rolled exhibits the highest yield strength (~248MPa) and the highest tensile strength (~382MPa) at room temperature, and has the greatest ultimate elongation (~697%) at 300°C. Therefore, the Mg–9Al–1Zn alloy sheet via a combination of extrusion and rolling possesses the best integrated performance in service at room temperature and presents the most excellent superplastic capacity at elevated temperature among all the three sheets. The results in this study would be of high industrial or scientific interest in industrial applications and superplastic preprocessing on magnesium alloys. •Effects of initial microstructures on the rolled microstructures and mechanical properties of AZ91 sheets were investigated.•All three rolled AZ91 sheets present a fine-grained recrystallized microstructure and a strong basal (0002) texture.•The extrusion-rolling AZ91 sheet possesses relatively excellent mechanical properties. [Display omitted]