摘要
The propagation mechanism of microcracks in nanocrystalline single crystal systems under uniaxial dynamic and static tension is investigated using the phase-field-crystal method.Both dynamic and static stretching results show that different orientation angles can induce the crack propagation mode,microscopic morphology,the free energy,crack area change,and causing fracture failure.Crack propagation mode depends on the dislocation activity near the crack tip.Brittle propagation of the crack occurs due to dislocation always at crack tip.Dislocation is emitted at the front end of the crack tip and plastic deformation occurs,which belongs to ductile propagation.The orientation angles of 9°and 14°are brittleductile mixed propagation,while the orientation angles of 19°and 30°are brittle propagation and no dislocation is formed under dynamic tension.The vacancy and vacancy connectivity phenomenon would appear when the orientation angle is14°under static tension,and the crack would be ductile propagation.While the orientation angle is 19°and 30°,the crack propagates in a certain direction,which is a kind of brittle propagation.This work has some practical significance in preventing material fracture failure and improving material performance.
作者
彭敦维
张云鹏
田晓林
侯华
赵宇宏
Dunwei Peng;Yunpeng Zhang;Xiaolin Tian;Hua Hou;Yuhong Zhao(School of Materials Science and Engineering,Xi’an University of Technology,Xi’an 710048,China;School of Materials Science and Engineering,North University of China,Taiyuan 030051,China;School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;Beijing Advanced Innovation Center for Materials Genome Engineering,University of Science and Technology Beijing,Beijing 100083,China)
基金
Project supported by the National Natural Science Foundation of China(Grant No.52074246)。
