In situ transmission electron microscopy observations of precipitation and a new orientation relationship between γ-Mg₁₇Al₁₂ and magnesium-based matrix in an Mg–Al–Zn–Sn alloy

Abstract

An in situ observation of the precipitation of γ-Mg₁₇Al₁₂ phase in a die-cast Mg–Al–Zn–Sn alloy was performed using a transmission electron microscope equipped with a heating stage maintained at 403 K for 100 min. The addition of a small amount of Sn to the AZ91 system accelerates the development of the γ-Mg₁₇Al₁₂ phase formed during continuous precipitation. A new orientation relationship between the γ-Mg₁₇Al₁₂ precipitate and α-Mg matrix was identified as .

Keywords:

• electron microscopy
• magnesium alloys
• aging
• precipitation
• age hardening
• orientation relationships

Acknowledgments

This research was supported by National Natural Science Foundation of China (Grant Nos. 51171130, 50771074 and 50571075) and the New Century Excellent Talents in University (Grant No. NCET-07-0640).