Mechanics of dynamic debonding

Singular fields around a crack running dynamically along the interface between two anisotropic substrates are examined. Emphasis is placed on extending an established frame work for interface fracture mechanics to include rapidly applied loads, fast crack propagation and strain rate dependent material response. For a crack running at non-uniform speed, the crack tip behaviour is governed by an instantaneous steady-state, two-dimensional singularity. This simplifies the problem, rendering the Stroh techniques applicable. In general, the singularity oscillates, similar to quasi-static cracks. The oscillation index is infinite when the crack runs at the Rayleigh wave speed of the more compliant material, suggesting a large contact zone may exist behind the crack tip at high speeds. In contrast to a crack in homogeneous materials, an interface crack has a finite energy factor at the lower Rayleigh wave speed. Singular fields are presented for isotropic bimaterials, so are the key quantities for orthotropic bimaterials. Implications on crack branching and substrate cracking are discussed. Dynamic stress intensity factors for anisotropic bimaterials are solved for several basic steady state configurations, including the Yoffe, Gol’dshtein and Dugdale problems. Under time-independent loading, the dynamic stress intensity factor can be factorized into its equilibrium counterpart and the universal functions of crack speed.

[1]  J. Lothe,et al.  Considerations of the existence of interfacial (Stoneley) waves in bonded anisotropic elastic half-spaces , 1985, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[2]  J. Lothe,et al.  On the existence of surface‐wave solutions for anisotropic elastic half‐spaces with free surface , 1976 .

[3]  E. Yoffe,et al.  LXXV. The moving griffith crack , 1951 .

[4]  T. C. T. Ting,et al.  Explicit solution and invariance of the singularities at an interface crack in anisotropic composites , 1986 .

[5]  Zhigang Suo,et al.  Singularities, interfaces and cracks in dissimilar anisotropic media , 1990, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[6]  K. Ingebrigtsen,et al.  Elastic Surface Waves in Crystals , 1969 .

[7]  C. Shih,et al.  Crack extension and kinking in laminates and bicrystals , 1992 .

[8]  John R. Rice,et al.  Mathematical analysis in the mechanics of fracture , 1968 .

[9]  Zhigang Suo,et al.  MECHANICS AND 1HERMODYNAMICS OF BRITILE IN1ERFACIAL FAILURE IN BIMATERIAL SYSTEMS , 1990 .

[10]  E. Gdoutos,et al.  Fracture Mechanics , 2020, Encyclopedic Dictionary of Archaeology.

[11]  M. Ortiz,et al.  Effect of decohesion and sliding on bimaterial crack-tip fields , 1990 .

[12]  A. N. Stroh.  Steady State Problems in Anisotropic Elasticity , 1962 .

[13]  Ares J. Rosakis,et al.  Quasi-static and dynamic crack growth along bimaterial interfaces: A note on crack-tip field measurements using coherent gradient sensing , 1991 .

[14]  J. Willis,et al.  Fracture mechanics of interfacial cracks , 1971 .

[15]  John W. Hutchinson,et al.  Dynamic Fracture Mechanics , 1990 .

[16]  A. Evans,et al.  The fracture energy of bimaterial interfaces , 1990 .

[17]  James R. Rice,et al.  Elastic Fracture Mechanics Concepts for Interfacial Cracks , 1988 .

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

[19]  E. Yoffe,et al.  The moving Griffith crack , 1951 .

[20]  Wu Kuang-Chong,et al.  Explicit crack-tip fields of an extending interface crack in an anisotropic bimaterial , 1991 .