Abstract :
The effect of a commercial hard anodizing
on the fatigue property of 2014 Al alloy which has been
solution heat treated and age hardened prior to the
hard anodizing of approximately 10 lm in thickness
have been investigated. The results indicated that
fatigue life in high stress region for aluminium alloy
samples hard anodized was shorter than that of the
other material condition which has been solution heat
treated and then age hardened (T6 heat treated), while
the life in low stress region was longer than that of the
material (T6 heat treated). However, such a coating to
the aluminium substrate gives rise to a significant
increase in fatigue strength of 107 cycle in comparison
with the as cast condition, but a much less increase in
comparison with T6 heat treated samples. From the
microscopic point of view, it has been observed that
fatigue fracture of samples hard anodized initiated in
the coating in high stress region in opposition to low
stress region in which fatigue fracture initiation started
on the interface between coating and substrate.
