A material is brittle if, when subjected to stress, it fractures with little elastic deformation and without significant plastic deformation. Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a sharp snapping sound.
Brittle fracture in glass
Brittle fracture in cast iron tensile testpieces
Brittleness diagrams titled "Deformation" (Russian: деформация)
Fracture is the appearance of a crack or complete separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displacement develops perpendicular to the surface, it is called a normal tensile crack or simply a crack; if a displacement develops tangentially, it is called a shear crack, slip band, or dislocation.
Ductile failure of a metallic specimen strained axially
Brittle fracture in glass
Fracture of an aluminum crank arm of a bicycle, where the bright areas display a brittle fracture, and the dark areas show fatigue fracture
Brittle cleavage fracture surface from a scanning electron microscope
