Fracture Mechanics of aV-peel Adhesion Test - Transition from a Bending Plate to a Stretching Membrane

A linear elastic solution is proposed for a “V-peel” adhesion test for a thin film adhered to a rigid substrate. The mechanical responses of a stiff plate-like coating under pure bending, a semi-flexible film under mixed bending and stretching, and a flexible membrane-like film under pure stretching are discussed. For delamination to occur, the mechanical energy release rate is shown to be G = χ(Fw₀/2bl) with χ a numerical constant varying from 3/2 for a plate-like disc to 3/4 for a thin flexible membrane.