Ductility fracture

Shear deformation was observed in the tension test indicating some ductility of these glasses before fracture. Ductile fracture of the specimen is generally characterized by shp bands and necking down before fracture. 

Brittle fracture Ductile fracture Shear fracture... 

Zahbruch/ duktiler Bruch tough fracture, ductile fracture... 

Simple fracture is the separation of a body into two or more pieces in response to an imposed stress that is static (i.e., constant or slowly changing with time) and at temperatures that are low relative to the melting temperatnre of the material. Fracture can also occur from fatigue (when cyclic stresses are imposed) and creep (time-dependent deformation, normally at elevated temperatnres) the topics of fatigue and creep are covered later in this chapter (Sections 8.7 throngh 8.15). Althongh applied stresses may be tensile, compressive, shear, or torsional (or combinations of these), the present discussion wiU be confined to fractnres that resnlt from uniaxial tensile loads. For metals, two fracture ductile fracture, modes are possible ductile and brittle. Classification is based on the ability of a material... 

An understanding of the mechanisms responsible for stress transfer provides the basis for prediction of the stress-strain curve of the composite and its mode of fracture (ductile vs. brittle). Such understanding and quantitative prediction may also serve as a basis for developing composites of improved performance through modification of the fibre-matrix interaction. This might be achieved, for example, through changes in the fibre shape, or treatment of the fibre surface. 

Item 3 would correspond to design techniques and structural evaluation methods. These would include evaluation methods for brittle fracture, ductile tearing, fatigue crack growth, creep crack growth, and buckling. 

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