Ductile Fracture
Definition
Fracture preceded by extensive plastic deformation, in which microvoids nucleate at inclusions, grow, and coalesce to form the fracture surface. The surface is rough, fibrous, and grey; energy absorption is high.
- Mechanism
- Microvoid nucleation, growth, coalescence
- Surface appearance
- Rough, fibrous, grey
- Energy absorption
- High, relative to brittle fracture
- Preceded by
- Extensive plastic deformation
Common questions
Why does high energy absorption matter when distinguishing ductile from brittle fracture?+
It tells an investigator the material deformed significantly before failing, which points toward overload or gradual force application rather than a sudden brittle event. This distinction informs whether a failure resulted from impact, fatigue, or material defect.
Can a single component fail with both ductile and brittle regions on the same fracture surface?+
Yes, mixed-mode fracture surfaces are common, for example in fatigue failures where a brittle striated region precedes a final ductile overload zone once the remaining cross-section can no longer bear the load.
Related terms
- Brittle Fracture
- Fracture with little or no plastic deformation, occurring by rapid cleavage through grains or along grain boundaries. The surface is flat, often...
- Cleavage
- Fracture by separation along specific crystallographic planes, typically {100} planes in body-centred-cubic metals. The fracture surface is flat at the grain scale...
- Cup-and-Cone Fracture
- The classic macroscopic appearance of ductile tensile fracture in round bar: a flat central zone (the cup) formed by void coalescence surrounded...
- Intergranular Fracture
- Fracture path running along grain boundaries rather than through grains. Indicates boundary weakness from segregation, embrittlement, or environmental attack, and produces a...
- SEM Fractography
- The use of scanning electron microscopy to image fracture surfaces at magnifications beyond the optical limit, revealing dimple size and distribution in...