中国物理B ›› 2013, Vol. 22 ›› Issue (1): 16201-016201.doi: 10.1088/1674-1056/22/1/016201

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Shielding effect of a nano-circular inclusion acting on semi-infinite wedge cracks

宋豪鹏, 高存法   

  1. College of Aerospace Engineering, State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics & Astronautics, Nanjing 210016, China
  • 收稿日期:2012-04-06 修回日期:2012-08-07 出版日期:2012-12-01 发布日期:2012-12-01
  • 基金资助:
    Project supported by the Postdoctoral Research Funds of Jiangsu Province, China (Grant No. 1002008B) and the China Postdoctoral Science Foundation (Grant No. 20110491416).

Shielding effect of a nano-circular inclusion acting on semi-infinite wedge cracks

Song Hao-Peng (宋豪鹏), Gao Cun-Fa (高存法)   

  1. College of Aerospace Engineering, State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics & Astronautics, Nanjing 210016, China
  • Received:2012-04-06 Revised:2012-08-07 Online:2012-12-01 Published:2012-12-01
  • Contact: Song Hao-Peng E-mail:hpsong@nuaa.edu.cn
  • Supported by:
    Project supported by the Postdoctoral Research Funds of Jiangsu Province, China (Grant No. 1002008B) and the China Postdoctoral Science Foundation (Grant No. 20110491416).

摘要: The model of a screw dislocation near a semi-infinite wedge crack tip inside a nano circular inclusion is proposed to investigate the shielding effect of nano inclusions acting on cracks. Utilizing the complex function method, the closed-form solutions of the stress fields in the matrix and the inclusion region are derived. The stress intensity factor, the image force, as well as the critical loads for dislocation emission are discussed in detail. The results show that the nano inclusion not only enhances the shielding effect exerted by the dislocation, but also provides shielding effect itself. Moreover, dislocations may be trapped in the nano inclusion even if the matrix is softer than the inclusion. This helps the dislocation shield crack, and reduces the dislocation density within the matrix.

关键词: screw dislocation, wedge crack, nano inclusion, shielding effect

Abstract: The model of a screw dislocation near a semi-infinite wedge crack tip inside a nano circular inclusion is proposed to investigate the shielding effect of nano inclusions acting on cracks. Utilizing the complex function method, the closed-form solutions of the stress fields in the matrix and the inclusion region are derived. The stress intensity factor, the image force, as well as the critical loads for dislocation emission are discussed in detail. The results show that the nano inclusion not only enhances the shielding effect exerted by the dislocation, but also provides shielding effect itself. Moreover, dislocations may be trapped in the nano inclusion even if the matrix is softer than the inclusion. This helps the dislocation shield crack, and reduces the dislocation density within the matrix.

Key words: screw dislocation, wedge crack, nano inclusion, shielding effect

中图分类号:  (Fracture)

  • 62.20.mm
62.20.mt (Cracks) 62.23.Pq (Composites (nanosystems embedded in a larger structure))