Fracture process zone concept and delamination of composite laminates

Abstract

Delaminations occur at the free edges of composite laminates because of high interlaminar stresses, which develop due to a mismatch in elastic properties between adjacent plies and the limited toughness of the matrix. The process of delamination is modelled using the concept of a fracture process zone. A finite element analysis that can be used with a constant or linear stress-displacement relationship within the fracture process zone is presented. It is found that the simple constant stress model gives an accurate prediction of the delamination on the free edge of a tensile specimen. © 1995.