While most structural and functional materials
are crystalline, many of their properties (e.g.
mechanical strength, electrical conductivity,
corrosion resistance) are actually determined by
defectsÊÐ deviations from the ideal
crystal structure. This includes point-, line-,
and planar defects, internal interfaces, and
surfaces. For understanding and controlling
materials properties, therefore, it is essential
to investigate their defect population, known as
the "microstructure."
This laboratory course demonstrates how heat
treatments (heating and cooling) of materials can
be employed to control their microstructure and
properties.
The following three examples will be
studied:
1. The effect of different heat treatments on
the presence of various phases in steels, the
spatial distribution of these phases, and the
resulting mechanical properties (hardness).
2. The effect of annealing on the volume
fraction and spatial distribution of second phase
precipitates in a lightweight alloy (Al--Mg--Si),
and the resulting mechanical properties
(strength, flow stress).
3. The effect of summit treatments on the
surface properties of glass, and the resulting
mechanical properties (fracture stress).
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