No. (At least not at the moment).
AIX will only run on specific IBM chips.
It supports a swag of 3rd parts drives/peripherals so I would hedge a bet that it could support some of the other internals but the kernal won't run on the 970 that the Mac uses (currently).
We have 7 XServes (I even have a test one for myself) and I had yellow dog linux running on mine for a while.
I would love to put either solaris (perhaps 10) or aix on them.