Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7991913 | Journal of Alloys and Compounds | 2018 | 10 Pages |
Abstract
In this study, as-cast alloy Mg-9Li-3Al-2.5Sr (LAJ932) ingots were extruded at different temperatures using an extrusion ratio of 28, and the underlying microstructural evolution and mechanical behavior were investigated. The results show that grains in the extruded LAJ932 alloy are much finer than those in the as-cast one, which indicates that the microstructural evolution during extrusion is governed by dynamic recrystallization. With increasing extrusion temperature, the grain size of the extruded alloy increases, and the strength decreases whereas the elongation increases. The alloy extruded at 250â¯Â°C possesses the highest strength of 238â¯MPa with an elongation of 18.1%, whereas1 the alloy extruded at 350â¯Â°C has the largest elongation of 21.6% with a strength of 208â¯MPa. The differences in microstructure characteristics between the α-Mg phase and β-Li phase in the alloy extruded at 250â¯Â°C suggest that continuous dynamic recrystallization (CDRX) occurs in the α-Mg phase during extrusion whereas the microstructure evolution in β-Li phase is governed by discontinuous dynamic recrystallization (DDRX). DDRX occurs in α-Mg phase to some extent and the fraction of DDRX grains in the alloys increases with increasing extrusion temperature.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Yan Yang, Xiaoming Xiong, Junfei Su, Xiaodong Peng, Haiming Wen, Guobing Wei, Fusheng Pan, Enrique J. Lavernia,