Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-01T21:31:20.321Z Has data issue: false hasContentIssue false

Discrete Dislocations Interacting with a Mode I Crack

Published online by Cambridge University Press:  10 February 2011

H.H.M. Cleveringa
Affiliation:
Delft University of Technology, Koiter Institute Delft, Mekelweg 2, 2628 CD Delft, The Netherlands
E. Van Der Giessen
Affiliation:
Delft University of Technology, Koiter Institute Delft, Mekelweg 2, 2628 CD Delft, The Netherlands
A. Needleman
Affiliation:
Brown University, Division of Engineering, Providence, RI 02912, USA
Get access

Abstract

Small scale yielding around a plane strain mode I crack is analyzed using discrete dislocation dynamics. The dislocations are all of edge character, and are modeled as line singularities in an elastic material. At each stage of loading, superposition is used to represent the solution in terms of solutions for edge dislocations in a half-space and a complementary solution that enforces the boundary conditions. The latter is non-singular and obtained from a linear elastic, finite element solution. The lattice resistance to dislocation motion, dislocation nucleation, dislocation interaction with obstacles and dislocation annihilation are incorporated into the formulation through a set of constitutive rules. A relation between the opening traction and the displacement jumps across a cohesive surface ahead of the initial crack tip is also specified, so that crack initiation and crack growth emerge naturally. Material parameters representative of aluminum are employed. Two cases are considered that differ in the strength and density of dislocation obstacles. Results are presented for the evolution of the dislocation structure and the near-tip stress field during the early stages of crack growth.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Giessen, E. Van der and Needleman, A., Modeling Simul. Mater. Sci. Eng. 3, 689735 (1995).Google Scholar
[2] Cleveringa, H.H.M., Giessen, E. Van der and Needleman, A., Acta Mat. 45, 31633179 (1997).Google Scholar
[3] Needleman, A., J. Mech. Phys. Solids 38, 289324 (1990).Google Scholar
[4] Tvergaard, V. and Hutchinson, J.W., J. Mech. Phys. Solids 40, 13771397 (1992).Google Scholar
[5] Suo, Z., Shih, C.F. and Varias, A.G., Acat Metall. Mater. 41, 15511557 (1993).Google Scholar
[6] Fleck, N.A. and Hutchinson, J.W., J. Mech. Phys. Solids 41, 18251857 (1993).Google Scholar
[7] Fleck, N.A. and Hutchinson, J.W., Adv. Appl. Mech. 33, 295361 (1997).Google Scholar
[8] Weertman, J., Lin, I.H. and Thomson, R., Acta Metall. 31, 473482 (1983).Google Scholar
[9] Hirsch, P.B. and Roberts, S.G., Scr. Metall. 23 925930 (1989).Google Scholar
[10] Nitzsche, V.R. and Hsia, K.J., Mat. Sci. Engng A 176 155 (1994).Google Scholar
[11] Zacharopoulos, N., Srolovitz, D.J. and LeSar, R., Acta Mat. 45, 37453763 (1997).Google Scholar
[12] Lubarda, V., Blume, J.A. and Needleman, A., Acta Metall. Mater. 41, 625642 (1993).Google Scholar
[13] Freund, L.B., Adv. Appl. Mech. 30, 166 (1994).Google Scholar
[14] Rose, J.H., Ferrante, J. and Smith, J.R., Phys. Rev. Lett., 47, 675678 (1981).Google Scholar
[15] Rice, J.R., Mech. Mat., 6, 317335 (1987).Google Scholar
[16] Cuitifio, A.M. and Ortiz, M., Model. Simul. Mat. Sci. Engin., 1, 255263 (1992).Google Scholar