Numerical analysis of directionally unstable crack propagation in adhesively bonded joints

This paper investigates the directional stability of crack propagation in adhesively bonded joints. First, an analytical model analyzing the energy balance during the crack propagation in double cantilever beam specimens is presented, and the directional stability of cracks is predicted. The results are consistent with the predictions made by Fleck, Hutchinson, and Suo (Int. J. Solids Struct. 27 (13) (1991) 1683) using a stress analysis approach, and also are consistent with experimental observations. Similar to the situation in homogeneous solids, cracks in adhesively bonded joints also tend to be directionally unstable when the T-stress is positive (tensile) whereas tend to be directionally stable when the T-stress is negative (compressive). Both interface mechanics and the finite element method are then employed to analyze the stress state at the crack tip and to predict crack trajectories. Through extending the criteria for direction of crack propagation to bi-material systems, the trajectory for directionally unstable cracks is simulated. The simulation result accurately reflects the alternating nature of directionally unstable cracks in adhesive bonds such as the characteristic length and the overall shape.

[1]  X. Zhu,et al.  Constraint effects on crack-tip fields in elastic-perfectly plastic materials , 2001 .

[2]  S. Schmauder,et al.  Composite Parameters and Mechanical Compatibility of Material Joints , 1988 .

[3]  T. S. Cook,et al.  Stresses in bonded materials with a crack perpendicular to the interface , 1972 .

[4]  D. Dillard,et al.  Chapter 11 - Crack path selection in adhesively bonded joints , 2002 .

[5]  A. J. Carlsson,et al.  Influence of non-singular stress terms and specimen geometry on small-scale yielding at crack tips in elastic-plastic materials , 1973 .

[6]  Hiroshi Tada,et al.  The stress analysis of cracks handbook , 2000 .

[7]  Anthony G. Evans,et al.  Kinking of a Crack out of an Interface: Role of In‐Plane Stress , 1991 .

[8]  H. Chai On the correlation between the mode I failure of adhesive joints and laminated composites , 1986 .

[9]  W. G. Knauss,et al.  II – On the Problem of Crack Extension in Brittle Solids Under General Loading , 1978 .

[10]  Z. Suo,et al.  Mixed mode cracking in layered materials , 1991 .

[11]  John W. Hutchinson,et al.  Singular behaviour at the end of a tensile crack in a hardening material , 1968 .

[12]  Yuh J. Chao,et al.  On the failure of cracks under mixed-mode loads , 1997 .

[13]  J. Rice,et al.  Slightly curved or kinked cracks , 1980 .

[14]  M. Williams,et al.  On the Stress Distribution at the Base of a Stationary Crack , 1956 .

[15]  H. Chai A note on crack trajectory in an elastic strip bounded by rigid substrates , 1986 .

[16]  Z. Suo Failure of Brittle Adhesive Joints , 1990 .

[17]  D. Dillard,et al.  Analysis of the Notched Coating Adhesion Test , 1999 .

[18]  F. Erdogan,et al.  On the Crack Extension in Plates Under Plane Loading and Transverse Shear , 1963 .

[19]  Norman A. Fleck,et al.  Brittle fracture of adhesive joints , 1992 .

[20]  R. Salganik,et al.  Brittle fracture of solids with arbitrary cracks , 1974 .

[21]  M. Williams The stresses around a fault or crack in dissimilar media , 1959 .

[22]  H. Chai The characterization of Mode I delamination failure in non-woven, multidirectional laminates , 1984 .

[23]  John A. Nairn,et al.  The Strain Energy Release Rate of Composite Microcracking: A Variational Approach , 1989 .

[24]  J. Rice A path-independent integral and the approximate analysis of strain , 1968 .

[25]  N. Fleck,et al.  Analysis of a wavy crack in sandwich specimens , 1992 .

[26]  Zhigang Suo,et al.  Sandwich test specimens for measuring interface crack toughness , 1989 .

[27]  J. Rice,et al.  Elementary engineering fracture mechanics , 1974 .

[28]  John W. Hutchinson,et al.  Crack deflection at an interface between dissimilar elastic-materials , 1989 .

[29]  Norman A. Fleck,et al.  Crack path selection in a brittle adhesive layer , 1991 .

[30]  David A. Dillard,et al.  The effect of the T-stress on crack path selection in adhesively bonded joints , 2001 .

[31]  John W. Hutchinson,et al.  Crack Paralleling an Interface Between Dissimilar Materials , 1987 .