Effect of rare earth addition on {10(1)over-bar2} twinning induced hardening in magnesium

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:720

Article

Imandoust, Aidin¹  Barrett, Christopher D.^2,3  El Kadiri, Haitham^2,3 

[1] Auburn Univ, Dept Mech Engn, Auburn, AL 36849 USA

[2] Mississippi State Univ, Dept Mech Engn, Mississippi State, MS 39762 USA

[3] Mississippi State Univ, Ctr Adv Vehicular Syst, Mississippi State, MS 39762 USA

关键词: Magnesium;    Rare earth;    Electron backscattering diffraction (EBSD);    Work hardening;    Extension twinning;   

DOI  :  10.1016/j.msea.2018.02.067

来源: Elsevier

【 摘 要 】

We investigated the effect of Gd and Ce additions in magnesium on sigmoidal hardening behavior associated with {10 (1) over bar2} twinning after extrusion. Compression along extrusion direction revealed that rare earth additions enhance the flow stress, while < c + a > softening was expected. This phenomenon has been explained by the enhancement of < c + a > dislocations activity and the ensuing increase in forest hardening due to solute drag. It is expected that dislocation transmutation of basal to prismatic will be enhanced during (10 (1) over bar2} twin growth in rare earth containing alloys, which would exacerbate < c + a > entanglement with the dislocation forests inside the twins. Forest hardening events overcompensated for the softening effects from lowering the critical resolved shear stresses of < c + a > dislocations, and resulted in higher flow stress for the binary rare earth containing alloys.

【 授权许可】

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