Effect of deformation temperature on plastic deformation mechanism of magnesium twin interface with void [变形温度对含空洞的镁孪晶界面塑性变形机制的影响]

作者：Tang J.-Q.; Yao J.-P.^*; Huang K.-X.; Hu Q.-Y.

来源：Journal of Plasticity Engineering, 2021, 28(4): 152-156.

DOI：10.3969/j.issn.1007-2012.2021.04.020

• Molecular dynamics
• Partial dislocations
• Single crystal magnesium
• Twin interface
• Void

The effect of deformation temperature on the tensile properties and the plastic deformation mechanism of magnesium twin interface with prefabricated nano-void defects was studied by molecular dynamics simulation with embedded atomic potential. The results show that defects such as incomplete dislocations, slip bands and stacking faults occur during plastic deformation. Both the Young's modulus and yield stress of the specimen are affected by deformation temperature, when deformation temperature increases from 100 K to 500 K, the Young's modulus decreases from 48.81 GPa to 38.5 GPa, and the yield stress decreases with the increase of deformation temperature. The reason is that with the increase of temperature, the thermal activation effect of the atom enhances, dislocation movement is easier to overcome obstacles, and plastic deformation performance is improved, which leads to lower yield stress. At the initial stage of deformation, with the increase of deformation temperature, the stacking fault on the grain boundary and twin interface increases, but the effect on the slip position is not obvious. In the serious deformation stage, the higher the temperature is, the more serious the deformation is, and the new dislocation continues to form, and the high-density dislocation entangles with each other, which leads to dislocation plug.

• 单位
  南昌航空大学