Precipitation microstructure and age-hardening response of an Mg–Gd–Nd–Zn–Zr alloy

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 534; pp. 1 - 6
• Main Authors: Li, J.H., Sha, G., Wang, T.Y., Jie, W.Q., Ringer, S.P.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.02.2012; Elsevier
• Subjects: Age hardening; Atom probe tomography; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Magnesium alloys; Materials science; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Precipitation; Solid solution, precipitation, and dispersion hardening; aging; Transmission electron microscopy; Treatment of materials and its effects on microstructure and properties; Precipitation; Transmission electron microscopy; Magnesium alloys; Age hardening; Atom probe tomography; Tomography; Aging; Microstructure; Precipitates; Atom probe
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2011.10.092

► The precipitate phases known as β″, β′ and β1 form during the ageing at 200°C. ► The solute elements Nd, Zn and Gd partition significantly into the precipitates. ► β1 precipitates produce more effective strengthening effect than β″ precipitates. Precipitates in an Mg–3.6Gd–2.8Nd–0.6Zn–0.4Zr (wt.%) alloy aged for times up to 70h at 200°C have been characterised using transmission electron microscopy and atom probe tomography. The precipitate phases known as β″, β′ and β1 occur during this ageing. The solute elements Nd, Zn and Gd partition significantly into these precipitates. The enhanced ageing hardening response after aged 70h is mainly attributed to the precipitation of β′ and β1 with a number density by a factor of 10 less than that of β″ and β′ precipitates formed after 3h ageing.