| |
· In addition to atomic scale
properties, the mesoscopic length scale of the crystallites is important in
creep behavior.
· The three
turbine blades shown in the photograph have different crystallite structures.
The blade on the left is polycrystalline
with its grains randomly oriented
with respect to the rotational tensile axis.
· The center blade has long, aligned crystallites with
their main axis parallel to the tensile axis. There is no shear across the
grain boundaries.
·
The last
blade is a single crystal with no internal boundaries. |
