Atomistic study of lattice trapping behavior for brittle fracture in bcc-iron

作者：Guo Ya Fang^*; Wang Chong Yu

来源：Computational Materials Science, 2007, 40(3): 376-381.

DOI：10.1016/j.commatsei.2007.01.019

• atomistic simulations
• lattice trapping
• anisotropy
• brittle fracture
• slip systems
• bcc-iron

The lattice trapping behavior for brittle fracture in bcc-iron has been studied by atomistic simulations. A pronounced anisotropy for brittle cleavage fracture of a mode I crack is observed in the discrete atomistic scale, and the preferred direction for cleavage is along the < 110 > direction on both {100} and {011} planes. The analysis of the atomic structure indicates that, due to the shear effect at the crack tip, the stacking faults or partial dislocations are formed before crack cleavage occurs. For the crack with a < 110 > crack front, shear occurs easily along the slip direction of bcc crystals, whereas for the crack with a < 100 > front, shear can only occur along the non-slip direction, and a strong lattice trapping is exhibited. We conclude that the anisotropy for cleavage fracture and the lattice trapping behavior are closely related with the slip systems of bcc crystals.

• 出版日期2007-9
• 单位清华大学; 北京交通大学; 中国地震局工程力学研究所