Crystal Growth - Morphology

Morphology

It is generally believed that the mechanical and other properties of the crystal are also pertinent the subject matter, and that crystal morphology provides the missing link between growth kinetics and physical properties. The necessary thermodynamic apparatus was provided by Gibbs study of heterogeneous equilibrium. He provided us with the clear definition of surface energy, by which the concept of surface tension is made applicable to solids as well as liquids. He also appreciated that an anisotropic surface free energy implied a non-spherical equilibrium shape, which should be thermodynamically defined as the shape which minimizes the total surface free energy.

It may be instructional to note that whisker growth provides the link between the mechanical phenomenon of high strength in whiskers and the various growth mechanisms which are responsible for their fibrous morphologies. (Prior to the discovery of carbon nanotubes, single-crystal whiskers had the highest tensile strength of any materials known). Some mechanisms produce defect-free whiskers, while others may have single screw dislocations along the main axis of growth — producing high strength whiskers.

The mechanism behind whisker growth is not well understood, but seems to be encouraged by compressive mechanical stresses including mechanically induced stresses, stresses induced by diffusion of different elements, and thermally induced stresses. Metal whiskers differ from metallic dendrites in several respects. Dendrites are fern-shaped like the branches of a tree, and grow across the surface of the metal. In contrast, whiskers are fibrous and project at a right angle to the surface of growth, or substrate.

Read more about this topic:  Crystal Growth

Other articles related to "morphology":

Altamura Man - Characteristics - Morphology
... have verified this aspect of typical Neanderthalians features (morphology of eye-sockets and upper orbit osseous thickening, lack of canine fossa and presence of a clear edge on the ...
Nanofiber Seeding - Description
... synthetic approach, called nanofiber seeding, was developed to control the bulk morphology of chemically synthesized electronic organic polymers ... yields polyaniline having granular morphology ... reaction is seeded by 2-4 mg (seed quantities) of added nanofibers, the bulk morphology changes dramatically from granular to nano-fibrillar ...
Morphology

Morphology may mean:

  • Morphology (linguistics), the study of the structure and content of word forms
  • Morphology (biology), the study of the form or shape of an organism or part thereof
  • Morphology (molecular), study of how the shape and form of molecules affect their chemical properties, dynamic reconfiguration and interactions
  • Morphology (astronomy), the shape of astronomical objects such as nebulae, galaxies, or other extended objects
  • Morphology (folkloristics), the structure of narratives such as folk tales
  • Geomorphology, the study of landforms
  • Mathematical morphology, a theoretical model based on lattice theory, used for digital image processing
  • Morphology (Architecture and Engineering), a research, which is based on theories of two dimensional and three dimensional symmetries, and then uses these geometries for planning buildings and structures.
  • River morphology, the field of science dealing with changes of river platform
  • Urban morphology, the study of growth and development of functions in cities
  • Morphological analysis (disambiguation)
  • Morphology (materials science), the study of shape, size, texture and phase distribution of physical objects.
  • Morphology (ideology), the study of the conceptual structure of ideologies, and the rules defining the admissibility of meanings into concepts.
  • Morphology (journal), ISSN 1871-5621
Gigantopithecus - Species - Gigantopithecus Blacki - Morphology
... The species lived in Asia and probably inhabited bamboo forests, since its fossils are often found alongside those of extinct ancestors of the panda ... Most evidence points to Gigantopithecus being a plant-eater ...

Famous quotes containing the word morphology:

    I ascribe a basic importance to the phenomenon of language.... To speak means to be in a position to use a certain syntax, to grasp the morphology of this or that language, but it means above all to assume a culture, to support the weight of a civilization.
    Frantz Fanon (1925–1961)