This last chart implies that 3M AMC is good to 550 C or about 1022 F.
Getting close to the 1200 F melting temperature of aluminum.
I suspect the upper practical limit is the same as aluminum or around
500 F. Rotor cooling would be critical.

Perhaps the best approach for a lighter weight rotor is what Mazda uses for the
rotor housings. A thin 4130 steel shell with a cast in aluminum-matrix composites
core for stability/stiffness and heat transfer. The apex seal slots could
then be hardened for exceptional long life.  Patent applied for :)

Paul Lamar ...No rotor no motor.

Paul,
You don't want to be making expensive rotors and throwing them away if the
apex seal slot widens through wear and stress, as they do now.
Consider a hardened triangular corner post, slotted to accept the apex seal
and machined to accept the corner side seal. This could be press fit into
place. My only concern would be the possibility of it moving with expansion
of the rotor, this could be overcome a number of ways including a small clip
into slot system. This way it would be easily removed as well.
George (down under)

A dwg would help George. High silicon content aluminum alloys expand
very little comparatively speaking.

This is for race cars. A Formula 1 engine is good for only
two races.
-- 
Paul Lamar ...No rotor no motor.

Paul,
I will work on a drawing, and of course I agree with what your saying -
however a lighter rotor will be a lighter installation all around,
especially with a Al end housings.
The man who can make it happen cost effectively, makes the money.
Of course I'm thinking you and Larry here.
Would be some considerable development costs, I would imagine.

BTW I'm sure I saw that Mazda either acquired or commissioned the liner
development, from another Company, but can't for the life of me remember it.
Perhaps if the Coy could be identified, they might be able to help.
George ( down under)

This would be for racing only and the super light weight  rotors would
cost thousands of dollars.