3: Ductile Fracture Surface
The images below are taken using a scanning electron microscope, and show the dimples characteristic of microvoid coalescence. Each dimple is a microvoid.
The left image is the area at the base of the cup or cone, and the right image is of the ductile fracture at the shear lip.
Ductile fracture is characterised by large amounts of plastic deformation. Proportionally large amounts of energy will therefore be required to induce this fracture. When designing a structure it is usually preferable for the material to fail in a ductile manner as there will be sufficient warning (evidence of deformation) before the final failure occurs.