Micromechanical approach to failure process in composites

The fracture resistance development mechanism has been analyzed in application to a class of composite materials. The composite reinforcing mechanism is based on formation of a system of restrictive forces imposed on the crack surface by reinforcing components, thus forming the process zone. A classical fracture mechanics modeling technique is employed, using the process zone concept and small or large scale analysis. An analytical approach developed for the analysis is based on consideration of discrete distribution of the reinforcing components, and is modeled as a line process zone ahead of a growing crack. This simplification of the geometry of the process zone allows one to obtain analytical solutions to the representative problems and to investigate detailed micromechanical aspects of the process. The developed methodology was applied to brittle matrix composites reinforced by unidirectional fibers, or reinforced by ductile particles, and to metal matrix composites reinforced by stiff fibers.