Login / Signup

Visualization and validation of twin nucleation and early-stage growth in magnesium.

Lin JiangMingyu GongJian WangZhiliang PanXin WangDalong ZhangY Morris WangJim CistonAndrew M MinorMingjie XuXiaoqing PanTimothy J RupertSubhash MahajanEnrique J LaverniaIrene J BeyerleinJulie M Schoenung
Published in: Nature communications (2022)
The abrupt occurrence of twinning when Mg is deformed leads to a highly anisotropic response, making it too unreliable for structural use and too unpredictable for observation. Here, we describe an in-situ transmission electron microscopy experiment on Mg crystals with strategically designed geometries for visualization of a long-proposed but unverified twinning mechanism. Combining with atomistic simulations and topological analysis, we conclude that twin nucleation occurs through a pure-shuffle mechanism that requires prismatic-basal transformations. Also, we verified a crystal geometry dependent twin growth mechanism, that is the early-stage growth associated with instability of plasticity flow, which can be dominated either by slower movement of prismatic-basal boundary steps, or by faster glide-shuffle along the twinning plane. The fundamental understanding of twinning provides a pathway to understand deformation from a scientific standpoint and the microstructure design principles to engineer metals with enhanced behavior from a technological standpoint.
Keyphrases
  • early stage
  • electron microscopy
  • squamous cell carcinoma
  • molecular dynamics simulations
  • white matter
  • radiation therapy
  • stress induced
  • room temperature
  • heavy metals
  • rectal cancer
  • monte carlo