Nil-Ductility Transition (NDT) Temperature?

The best data for ductile brittle transition temperatures has been done for AISI steels and not ASTM steels. Personally I don't know the reason for this, I can only summize that since most Met Es are ASM members and ASM seems to prefer that nomenclature over ASTM's.

Anyway, can you give the exact chemical composition of your alloy for conversion? Otherwise if this is a trade secret I would say do the Charpy Impact testing yourself to determine the NDT since Charpy testing is a lot of fun. A good whack and the top half of the sample flies across the room. Mainly this proves that a good metallugist is just a glorified blacksmith with a calibrated hammer, but I suppose there is some good data in there too.