The relationship between microstructure and creep resistance in die-cast magnesium–rare earth alloys

Received 19 November 2009; received in revised form 28 January 2010; accepted 2 February 2010. published online 08 February 2010.

Abstract

Die-cast Mg–La, Mg–Ce and Mg–Nd binary alloys varying in composition have been used to investigate creep resistance and its relation to microstructure. The remarkable differences in creep resistance observed in these alloys are shown to be related to different levels of rare earth (RE) solute supersaturated in the α-Mg matrix. The results seem to suggest that strengthening of the α-Mg matrix by solid solution and/or precipitation is more important than grain boundary reinforcement by intermetallic phases for the creep resistance of Mg–RE alloys.

Keywords: Magnesium alloys, Creep, Rare earth, Precipitation, Solid solution

a CAST CRC, Department of Materials Engineering, Monash University, Victoria 3800, Australia

b CAST CRC, CSIRO Process Science and Engineering, Clayton, Victoria 3169, Australia

Corresponding author. Tel.: +61 3 99059297; fax: +61 3 99054940.

PII: S1359-6462(10)00071-0

doi:10.1016/j.scriptamat.2010.02.005

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