METAL LINK
This link is presented in metals and alloys to form metallic glasses. Nature
link: Red crystal ions hardware (very electropositive elements) where the valence electrons are exchanged quickly.
Examples are substances that have: all metals, Au, Na, Fe, Ag, alloys such as steels, amalgams of mercury, copper and its alloys Cu - Zn, Cu-Ni, Cu - Sn, etc.
Properties derived from this type of link. Melting points, high boiling, metallic luster, hardness, malleability (rolling, stretching, bending), ductility (thread, wire), high electrical and thermal conductivity.
Another way to describe the metallic bonding is the existence of positive ions in a "sea electron gas" due to mobility of electrons, this mobility is due to the electrical conductivity and malleability.
In the "electron gas model" of metals, a regularly ordered lattice of positively charged metal ions is surrounded by electrons that can move freely. The easy mobility of the electron gas is responsible for the good electronic conductivity and thermal properties of metals.
If moving parts of a metallic glass, one over the other by a mechanical action (a). Each component in each new position above the same neighborhood, therefore, displacement, and thus the malleability of a metal, are easily possible without losing cohesion. By contrast, in an ionic crystal (b) components, by moving, are parties to the same charge: promotes mutual repulsion easily break the glass.
(a)
(b)
Note: The examples will be seen in class to visualize the diagrams, and drawings that does not accept the Blog.
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