Fracture Mechanics: Crack Growth and Stability

This lecture covers the initiation and stability of crack propagation, including the R-curve behavior in materials where crack propagation can lead to different outcomes such as constant, rising, or decreasing resistance. It also discusses the cohesive zone in fiber-reinforced composites, modeling crack stability and growth, and the experimental R-curve. The instructor explains the concepts of crack instability, the effect of initial crack length on instability, and the traction laws commonly used in finite element modeling. Additionally, the lecture explores the cohesive zone modeling using the J-integral and various empirical models for fatigue crack growth.