Energy Balance Approaches to Fracture
Differentiating produces the equation:
- This states that fracture will occur if the difference
between the work done by external forces and the increase in strain energy
of the body is sufficient to supply the energy required for fracture
- The energy required for fracture is the energy for plastic
deformation added to the energy to form new surfaces
- The left side of the equation is known as the Griffith’s
crack extension force, G (Strain
energy release rate)
- Fracture occurs when G
³ 2g