Plane Strain Fracture Toughness
Kc depends on the thickness of plate in question up to a
certain point when it becomes constant
- This constant value is known as the plane strain fracture
toughness denoted by:
- The I subscript corresponds to a mode I crack displacement
- KIc values are used most often because
they represent the worst case scenario
- Brittle materials have low KIc values, giving to catastrophic
failure
- ductile materials usually have much larger KIc values
- KIc depends on temperature, strain rate,
and microstructure
- Increases as grain size decreases
