In situ observation of transmission and reflection of dislocations at twin boundary in CoCrNi alloys


The deformation mechanism of CoCrNi alloy with high density of annealing twins was studied by in situ transmission electron microscopy. Dislocation transmission and reflection at the twin boundary were observed during in situ loading. We characterized these reaction processes by combining TEM, dislocation theory and crystallography of twin. Twin boundary not only strengthens the material by impeding the motion of dislocation, but also acts as dislocation source to produce large of slip bands. These processes generate large of slip bands to accommodate the plastic deformation or strengthening material.

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Corresponding author

Correspondence to XiaoFang Yang.

Additional information

This work was supported by the National Natural Science Foundation of China (Grant Nos. 51571046 and 51421001), the Fundamental Research Funds for the Central Universities (Grant No. 2018CDJDCL0019), and the “111”Project (Grant No. B16007) by the Ministry of Education and the State Administration of Foreign Experts Affairs of China.

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Liang, Y., Yang, X., Ming, K. et al. In situ observation of transmission and reflection of dislocations at twin boundary in CoCrNi alloys. Sci. China Technol. Sci. 64, 407–413 (2021).

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  • dislocation
  • transmission
  • reflection
  • TEM
  • CoCrNi alloys