Fracture Mechanics: Toughening Mechanisms and Resistance Curve

This lecture covers the concept of maximum toughening in fracture mechanics, analyzing stress intensity at the crack tip during crack growth, and separating atomistic tractions associated with surface energy. It also discusses the resistance curve, measuring the crack's resistance to growth, and presents examples of resistance curves in different materials. The lecture further explores the nonlinear cohesive zone near the crack tip, the mechanics of material separation processes, and the energy dissipation mechanisms in fiber-reinforced composites. It concludes with a discussion on elastic-plastic ductile failure, crack-tip energy dissipation, and the generalization of fracture concepts for ductile materials.