Residual strain energy in elastoplastic adhesive and cohesive fracture

The problem of peeling an elastoplastic strip from a rigid substrate is re-examined. The mechanics of combined flow and fracture are expressed algebraically, and in terms of work areas both under load and unloaded. The importance of residual elastic strain energy becomes apparent in the analysis and it is shown that determinations of work of fracture from partitioned areas may be significantly in error if residual strain energy is neglected. The extension of the treatment to cohesive fracture is discussed, and it is shown that Turner's I term relating to unloaded work areas should include a residual strain energy component. As an algebraic solution to the problem is available over the whole range of elastoplastic fracture, it is possible to construct an R6 failure assessment diagram over the whole range of deformation.