Precipitation of secondary phase in Mg-Zn-Gd alloy after room-temperature deformation and annealing

• Published in: Journal of materials research and technology Vol. 7; no. 2; pp. 135 - 141
• Main Authors: Huang, Hua, Miao, Hongwei, Yuan, Guangyin, Chen, Chunlin, Wang, Zhongchang
• Format: Journal Article
• Language: English
• Published: Elsevier Editora Ltda 01.04.2018; Elsevier
• Subjects: Annealing; Deformation; Mg alloys; Precipitation; Quasicrystal; Annealing; Precipitation; Deformation; Quasicrystal; Mg alloys
• ISSN: 2238-7854
• DOI: 10.1016/j.jmrt.2017.04.006

•Secondary phase precipitates for as-deformed Mg-Zn-Gd alloy were characterized.•Different defects for as-deformed Mg-Zn-Gd alloy were characterized.•Precipitates in as-deformed and as-annealed samples were characterized. Mg-Zn-RE alloys reinforced with quasicrystals have been investigated extensively because they show excellent balance in mechanical properties. Here, we perform deformation and annealing for Mg-1.50Zn-0.25Gd (at.%) alloy at various temperatures, aimed to gain nanoscale precipitates. We find that after the room-temperature compression, the non-basal dislocation, stacking fault and twining are identified in the as-deformed samples, offering clear evidence that these deformation mechanisms can accommodate room-temperature deformation. We also perform systematic transmission electron microscopy observations of the precipitates in both the as-deformed and as-annealed samples. The results identify the formation of a large amount of secondary-phase precipitates, I-phase and MgZn2, when annealed at 200°C, and precipitation of a small amount of W-phase when annealed at 400°C.