Search results
Results from the WOW.Com Content Network
The plastic deformation of ductile metals is important as it can be a sign of the potential failure of the metal. Yet, the point at which the material exhibits a ductile behavior versus a brittle behavior is not only dependent on the material itself but also on the temperature at which the stress is being applied to the material.
These mechanisms can overlap in the brittle-ductile settings. Deformation mechanisms are commonly characterized as brittle, ductile, and brittle-ductile. The driving mechanism responsible is an interplay between internal (e.g. composition, grain size and lattice-preferred orientation) and external (e.g. temperature and fluid pressure) factors.
Toughness is related to the area under the stress–strain curve.In order to be tough, a material must be both strong and ductile. For example, brittle materials (like ceramics) that are strong but with limited ductility are not tough; conversely, very ductile materials with low strengths are also not tough.
Stress–strain curve for brittle materials compared to ductile materials. Some common characteristics among the stress–strain curves can be distinguished with various groups of materials and, on this basis, to divide materials into two broad categories; namely, the ductile materials and the brittle materials. [1]: 51
For perfectly brittle materials, yield strength and ultimate strength are the same, because they do not experience detectable plastic deformation. The opposite of brittleness is ductility . The toughness of a material is the maximum amount of energy it can absorb before fracturing, which is different from the amount of force that can be applied.
The failure of a material is usually classified into brittle failure or ductile failure . Depending on the conditions (such as temperature, state of stress, loading rate) most materials can fail in a brittle or ductile manner or both. However, for most practical situations, a material may be classified as either brittle or ductile.
The least brittle structural ceramics are silicon carbide (mainly by virtue of its high strength) and transformation-toughened zirconia. A different philosophy is used in composite materials, where brittle glass fibers, for example, are embedded in a ductile matrix such as polyester resin. When strained, cracks are formed at the glass–matrix ...
Those two phenomenon are competitive mechanisms (although they are not mutually exclusive and can coexist [8]), with shear yielding being the more ductile failure mode because it involves the deformation of significant volume of the material while crazing is a more localized phenomenon ad it is more often associated with brittle failure. Shear ...