Fracture of ductile materials (Dissipated energy)

Description

In ductile materials, a plastic zone develops at the tip of the crack. The plastic loading and unloading cycle near the crack tip leads to the dissipation of energy as heat. So an additional energy is needed for crack growth in ductile materials when compared to brittle materials. Irwin’s strategy was to partition the energy into two parts: the thermodynamic driving force for fracture and the dissipated energy, which provides the thermodynamic resistance to fracture.