Especially, in the gas turbine blades,
Inconel 738 LC and CM 247 LC have been mainly used
as the substrate of blade’s components. Since the gas
turbine blades are rotating to generate the power, this
makes the vibration between blades and blade wheel, so
called “dovetails”. This induced vibration acts the
fretting wear. The damage level of fretting wear is
related with the surface shape such as the roughness.
Therefore, we can reduce the damage level of fretting
wear by control the roughness. In this paper, the fretting
test was conducted under the 3 steps-roughness (Ra
2.5um, 0.7um, 0.02um) to verify the characteristics of
the fretting wear depending on the roughness changes.
The results show that the friction coefficient of fretting
was decreasing as the roughness was increasing.
Therefore, the main wear mechanism is adhesive wear
since the friction coefficient shows higher in smoother
surface. The fretting wear of CM247LC is less affected
by the roughness change than Inconel738LC. However,
the Inconel 738 LC may have better performance than
CM247LC in 2.5um of Ra.