Cracks in composite materials: A compilation of stress solutions for composite systems with cracks

Composites offer great promise as light weight and strong materials for high performance structures. One of the major advantages of these materials as compared with metals is the basic way in which heterogeneity resist crack extension. In a fiber/matrix composite system, the fibers tend to cause cracks to form at closer spacing and delay the formation of a large crack. The enhancement of local failure such as fiber breaking, matrix cracking and interface debonding further reduces the energy level which might have otherwise reached the point of catastrophic failure. Even though substantial tests have been made on composite materials, little has been gained in the understanding and development of a predic­ tive procedure for composite failure. There are fundamental difficulties associated with incorporating the nonhomogeneous and anisotropic prop­ erties of the composite into the continuum mechanics analysis. Additional uncertainties arise from voids and defects that are introduced in the composite during manufacturing. Even a small quantity of mechanical imperfections can cause a marked influence on the composite strength. Moreover, the interface properties between the fibers and matrix or bonded laminae can also affect the load transmission characteristics significantly. It would be impossible to establish predictive procedures for composite failure unless realistic guidelines could be developed to control the manufacturing quality of composite systems.

Table of Contents:
1 Cracks in materials possessing homogeneous anisotropy.- 1.1 Introduction.- 1.2 Anisotropic elasticity.- 1.3 Plane and anti-plane problems of cracks in anisotropic materials.- 1.4 Penny-shaped crack in transversely isotropic bodies of infinite extent.- 1.5 A finite width orthotropic body with a central crack.- 1.6 Through crack in an orthotropic layer of finite height.- 1.7 Transversely isotropic cylinder containing a penny-shaped crack.- 1.8 Transversely isotropic layer containing a penny-shaped crack.- 1.9 Bending of anisotropic plates with cracks.- 1.10 Generalized plane deformation of aniostropic materials with cracks.- 1.11 Concluding remarks.- 1.12 Appendix: Method of solution for solving dual integral equations.- References.- 2 Nonhomogeneous materials with cracks.- 2.1 Introduction.- 2.2 Shear modulus varying a direction normal to the plane crack.- 2.3 Interaction of axial inhomogeneity with a penny-shaped crack.- 2.4 Appendix: Stress field and coefficient for a plane crack in nonhomogeneous solid.- References.- 3 Interface cracks in bimaterial systems.- 3.1 Introduction.- 3.2 Straight line cracks between two dissimilar media.- 3.3 Bimaterial solid debonded over a penny-shaped region.- 3.4 Cracks normal to bimaterial interface.- 3.5 Bending of bimaterial plates with cracks at and normal to interface.- 3.6 Appendix: Crack tip stress field and stress intensity factor solutions.- References.- 4 Composite material with a cracked layer and fiber.- 4.1 Introduction.- 4.2 A cracked layer sandwiched between two half-planes.- 4.3 Layered composite with a crack normal to interface.- 4.4 Penny-shaped crack parallel to interface of layered composite.- 4.5 Embedded cylinder with a crack normal to the interface.- 4.6 Cracks in composites with orthotropic layers.- References.- 5 Dynamic response of dissimilar materials with cracks.- 5.1 Introduction.- 5.2 Parallel crack in a sandwiched layer.- 5.3 Sandwiched layer with a crack normal to interface.- 5.4 Embedded penny-shaped crack parallel to composite interface.- 5.5 Cracked cylindrical fiber embedded in a matrix.- 5.6 Anti-plane shear of interface rectangular cracks in layered orthotropic dissimilar materials.- 5.7 Orthotropic layered composite debonded over a penny-shaped region subjected to sudden shear.- 5.8 Diffraction of time-harmonic waves by interface cracks in dissimilar media.- 5.9 Moving cracks in layered media of dissimilar materials.- Appendix: Inverse Laplace transform of dynamic stress intensity factor.- References.- 6 Plane extension and bending of laminate composite plates with cracks: static and dynamic loading.- 6.1 Introduction.- 6.2 A brief review of existing laminate plate theories.- 6.3 A laminate plate theory with boundary layer.- 6.4 Sudden extension of a cracked laminate.- 6.5 Bending theory of laminated plate: static and dynamic.- References.- Author’s Index.