The majority of engineering metals experience moderately ductile failure.
In uniaxial tension this failure mode has a characteristic appearance known as cup and cone fracture.
Cup and cone fracture occurs as a stepwise process. Each step involved in the formation of the fracture surface can be seen below.
2. Microvoid Occurance
3. Microvoid Coalescence
4. Fast Fracture
5. Shear Lip