Brittleness

The brittleness indicates the degree to which a material can plastically deform before it breaks. This material property can be determined in the tensile test:

• Brittle materials tear near the elastic limit without or with little plastic deformation ( brittle fracture ). Such materials usually possess a high hardness, such as diamond, carbides, nitrides, salts and ceramics, but, for example, cast iron and bakelite.
• In contrast, ductile materials - including many metals and plastics - comparatively far plastically deformed before they break through the deformation ( ductile fracture ).

The brittleness of a material increases with decreasing temperature.

Embrittlement

Several factors can cause a material is brittle, when he was in new condition. This process is called embrittlement. Examples:

• Plastics containing plasticizer brittle when the plasticizer to escape from them. The leakage is promoted by environmental factors such as ultraviolet radiation or high temperatures.
• Iron and steel become brittle under the influence of radiation. Meeting neutrons on iron atoms they encounter this from their ancestral lattice sites away ( " impurities in the crystals "). Each weggestoßene iron atom displaced in turn neighboring atoms from their places; results in a cascade of collisions that form cluster of defects.
• For some types of steel, it comes with storage of hydrogen to hydrogen embrittlement.

Other meanings

From brittleness is also called as a character trait of people ( " He or she is brittle "). Among them, a human being is seen, which is not easily accessible communicatively or emotionally not particularly open. The deformability of the material is thus transferred to a person and their communicative and emotional adaptability. A brittle person is " too hard, too inflexible " for an intensive exchange of words, thoughts, or feelings.