Grain growth and texture evolution during annealing in an indirect-extruded Mg–1Gd alloy

• Published in: Journal of alloys and compounds Vol. 585; pp. 111 - 119
• Main Authors: Wu, W.X., Jin, L., Zhang, Z.Y., Ding, W.J., Dong, J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01-02-2014; Elsevier
• Subjects: Annealing; Cross-disciplinary physics: materials science; rheology; EBSD; Evolution; Exact sciences and technology; Grain growth; Grains; Magnesium; Magnesium base alloys; Materials science; Other heat and thermomechanical treatments; Physics; Strengthening; Surface layer; Texture; Treatment of materials and its effects on microstructure and properties; Annealing; Magnesium; Grain growth; Texture; EBSD; Ductility; Formability; Quenching; Hardening; Indirect extrusion; Impurities; Gadolinium additions; Recrystallization; Formation mechanism
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2013.09.028

•〈21¯1¯1〉 RE-texture component is not observed in the as-extruded Mg–1Gd sample.•〈21¯1¯1〉 texture strengthens during annealing due to the preferred grain growth.•The driving force of preferred grain growth is the difference in stored energy.•Abnormal growth of the 〈101¯0〉 grain takes place during long-time annealing.
RE (rare earth)-texture component has been reported to be responsible for improved formability and ductility in RE-containing Mg alloys. Grain growth and texture evolution during annealing of Mg–1Gd alloy was investigated after indirect extrusion and quenching to reveal the formation mechanisms of the RE texture component. In the as-extruded Mg–1Gd sample, both the recrystallized grains and large elongated grainsare oriented mainly with 〈101¯0〉 orientation parallel to the extrusion direction (ED). The preferred growth of the 〈21¯1¯1〉 grain with its 〈21¯1¯1〉 orientation parallel to ED has been observed during recrystallization annealing, leading to the gradual strengthening of 〈21¯1¯1〉 RE-texture component at the expense of the 〈101¯0〉 component with increasing annealing temperature. The driving force for the preferred grain growth is the difference in stored energy between the 〈21¯1¯1〉 grains and the 〈101¯0〉 grains. Abnormal growth of the 〈101¯0〉 grain takes place during long-time annealing, resulting in the strengthening of 〈101¯0〉 component texture, which can be explained by a texture effect.