Influence of the Cone Crack Geometry on the Strength Degradation
The presence of surface compressive residual stress in a laminated material enhance the resistance of the component by reducing the stress intensity factors acting on the cracks -either natural or artificial- existing in the surface. Fissures in the form of cone crack are often generated by blunt contact in service, that can affect the functionality as well as the strength of the material. In this work, a two-steps analysis of the effect of residual stresses on the geometry of cone crack and how this change in geometry influences the far-field strength of the material was performed by means of a Finite Elements model and of experimental observations. In the first part, an automatic incremental model was formulated, which allowed to establish the crack shapes that were used in the second part for simple four-points test models. It was observed that residual stresses change considerably the crack shape, with important implications in the design of contact-damage tolerance, and that this reflects on corresponding changes in the strength.
Marc Anglada et al.
L. Ceseracciu et al., "Influence of the Cone Crack Geometry on the Strength Degradation", Key Engineering Materials, Vol. 333, pp. 255-258, 2007