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,-Increased ability to plastic deformation.
The presence of these properties and characterizes
the metallic state of
matter. Metals are divided into two groups:
Ferrous: iron, manganese and chromium.,
-Non-ferrous: -all the rest.
Non-ferrous metals to different attributes are divided into subgroups:
-Heavy, with a density greater 5g/cm ?.
-Light, with a density of up to 5 g / cm ?.
-Refractory, whose melting point is higher than that of iron.
-Fusible.
-Rare.
-Noble.
Atomic crystal structure of metals.
Under the atomic crystal structure understand the relative position of the atoms,
which exists in the crystal. Crystal consists of atoms
arranged in a particular
order, which is periodically repeated in three dimensions. Describing the
atomic crystal structure uses the concept of spatial or lattice. The crystal lattice
is an imaginary three-dimensional network whose nodes are the atoms forming
the metal. The vast number of technically important
metals forms one of the
following grids: In the body-centered cubic lattice of atoms located at the sites
of the cell and one atom at the center of the cube. In the face-centered cubic
lattice of atoms at the corners of the cube and in the center of each face. In the
hexagonal lattice of atoms at the corners and in the center of hexagonal prisms
bases and three atoms in the central plane of the prism.
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