Superplastic characteristics and forming of LZ91 Mg-Li alloy sheet

Magnesium-lithium (Mg-Li) alloys, due to their high specific strength, have great potential in the modern aviation industry. The superplastic characteristics, microstructure evolution, mechanical properties, and forming process of LZ91 Mg-Li alloys at 200°C–300°C were studied in this paper. Tensile...

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Bibliographic Details
Main Authors: Shi-jun Shen, Shao-song Jiang, Mei Zhan
Format: Article
Language:English
Published: SAGE Publishing 2022-05-01
Series:Advances in Mechanical Engineering
Online Access:https://doi.org/10.1177/16878132221100644
Description
Summary:Magnesium-lithium (Mg-Li) alloys, due to their high specific strength, have great potential in the modern aviation industry. The superplastic characteristics, microstructure evolution, mechanical properties, and forming process of LZ91 Mg-Li alloys at 200°C–300°C were studied in this paper. Tensile tests show that the optimal elongation of tensile specimens is 812.6% at 300°C under a strain rate of 5 × 10 −4  s −1 . The flow stress of the material increases with strain during the high-temperature tensile testing due to the grain coarsening . Meanwhile, low dislocation densities were observed during tension, which is not sufficient for dynamic recrystallisation to occur. The finite element method is used to investigate the forming schemes of a narrow-mouth box component. Finally, this component was manufactured by the powder pressure bulging process at 300°C experimentally.
ISSN:1687-8140