skip to main content

Title: Precipitation process in a Mg–Gd–Y alloy grain-refined by Al addition

The precipitation process in Mg–10Gd–3Y (wt.%) alloy grain-refined by 0.8 wt.% Al addition has been investigated by transmission electron microscopy. The alloy was given a solution treatment at 520 °C for 6 h plus 550 °C for 7 h before ageing at 250 °C. Plate-shaped intermetallic particles with the 18R-type long-period stacking ordered structure were observed in the solution-treated state. Upon isothermal ageing at 250 °C, the following precipitation sequence was identified for the α-Mg supersaturated solution: β″ (D0{sub 19}) → β′ (bco) → β{sub 1} (fcc) → β (fcc). The observed precipitation process and age hardening response in the Al grain-refined Mg–10Gd–3Y alloy are compared with those reported in the Zr grain-refined counterpart. - Highlights: • The precipitation process in Mg–10Gd–3Y–0.8Al (wt.%) alloy has been investigated. • Particles with the 18R-type LPSO structure were observed in the solution state. • Upon ageing at 250 °C, the precipitation sequence is: β″ → β′ → β1 (fcc) → β. • The Al grain-refined alloy has a lower hardness than the Zr refined counterpart.
Authors:
 [1] ;  [2] ;  [3] ;  [3] ;  [1] ;  [1] ;  [4] ;  [1] ;  [4]
  1. National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240 (China)
  2. (Australia)
  3. CAST Cooperative Research Centre, Department of Materials Engineering, Monash University, Victoria 3800 (Australia)
  4. (China)
Publication Date:
OSTI Identifier:
22288733
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 88; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AGE HARDENING; FCC LATTICES; HARDNESS; MAGNESIUM ALLOYS; PARTICLES; PRECIPITATION; TRANSMISSION ELECTRON MICROSCOPY