
Metallography
Metallography is the study
of the structure of metals. Metallurgists study the affect
that the composition, thermal and mechanical processing, and the
environment has on the structure.
The structure of metals is
usually evaluated using visual, optical, electron microscopy, x-ray
spectroscopy, x-ray diffraction examination techniques, and
quantitative metallography.
Variables that affect the microstructure include
the environment that the metal/alloy is in service, the composition,
corrosion, cracking, the conditions that the metal/alloy is
processed, machining, welding and more.
Metals
In most
cases, metals, such as steels, copper, and aluminum, are composed of
a collection of crystals and/or phases. Metals can be formed
from a single element, such as pure copper, or from two or more
elements, such as brass (copper and zinc) or steel (iron and
carbon).
Metals
formed from two or more elements are called alloys. Crystals
within the metal, with different compositions and/or crystal
structure, are called phases. The composition, crystal
structure, and the arrangement and shape of the crystals and phases
control the properties (mechanical and chemical) of the metal.
Examples of
Metallography (coming soon)