Microstructure and tensile properties of new type of hot rolled Mg–3Sn–1Zn alloy sheet at elevated temperatures

Abstract

Uniaxial tensile tests of a new type of hot rolled Mg–3Sn–1Zn (TZ31) alloy have been investigated within the temperature range of 25 to 200°C. The elongation to failure ϵ_f increases from 21·9% at 25°C to 79·0% at 200°C, while the 0·2% offset yield strength and peak true strength σ_p decrease from 141 to 60 MPa and from 264 to 91 MPa respectively. The thermal stability of globular Mg₂Sn precipitates is beneficial to the strength of the rolled TZ31 alloy at elevated temperatures. However, dynamic recovery and dynamic recrystallisation play an important role in the elevated temperature elongation. Results obtained here can be used as a reference to develop inexpensive new types Mg alloys with potential for applications at elevated temperatures.

Keywords:

• Magnesium alloy
• Microstructure
• Recrystallisation
• Mechanical properties

Acknowledgements

Financial supports from the Natural Science Foundation of China (no. 51271086) and the Doctoral Fund of Ministry of Education of China (no. 20120061110031) are greatly acknowledged. Partial financial supports are from the Natural Science Foundation of Jilin Province (no. 201115010) and the National Key Technologies R&D Program (no. 2011BAE22B03).