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Dislocation Behavior and Grain Boundary Segregation of Mg–Zn Alloys

  • Hyo-Sun Jang
  • Byeong-Joo LeeEmail author
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

Mg–Zn solid solutions have been reported to show 14–21% tensile elongation after rolling and annealing, but their textures exhibit strong basal texture similar to pure Mg. This phenomenon contrasts with the case in Mg–Y solid solutions showing good RT ductility and weakened basal textures. To reveal the mechanism of the good ductility and strong basal texture of Mg–Zn solid solutions at RT, we investigated the effect of Zn on Mg alloys using atomistic simulations. The simulations show that Zn can activate <c + a> slip by reducing critical resolved shear stress anisotropy among slip systems, thereby improving ductility. It is also found that grain boundary segregation tendency of Zn is low. The grain boundary segregation is known to affect twinning and recrystallization which can modify the texture evolution process. From the low grain boundary segregation of Zn, Mg–Zn alloys are expected to yield a texture similar to that of pure Mg.

Keywords

Magnesium alloys <c + a> slip Grain boundary segregation Molecular dynamics Monte Carlo simulation 

Notes

Acknowledgements

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2016R1A2B4006680).

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringPohang University of Science and Technology (POSTECH)PohangRepublic of Korea

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